blob: ba45a84e428703ced449952e61be8140d155fab2 [file] [log] [blame]
Arjan van de Venf71d20e2006-06-28 04:26:45 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 Copyright (C) 2002 Richard Henderson
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003 Copyright (C) 2001 Rusty Russell, 2002, 2010 Rusty Russell IBM.
Linus Torvalds1da177e2005-04-16 15:20:36 -07004
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
9
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
14
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18*/
Paul Gortmaker9984de12011-05-23 14:51:41 -040019#include <linux/export.h>
Paul Gortmaker8a293be2016-07-23 14:01:45 -040020#include <linux/extable.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/moduleloader.h>
Steven Rostedt (Red Hat)af658dc2015-04-29 14:36:05 -040022#include <linux/trace_events.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/init.h>
Alexey Dobriyanae84e322007-05-08 00:28:38 -070024#include <linux/kallsyms.h>
Kees Cook34e11692012-10-16 07:31:07 +103025#include <linux/file.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040026#include <linux/fs.h>
Roland McGrath6d760132007-10-16 23:26:40 -070027#include <linux/sysfs.h>
Randy Dunlap9f158332005-09-13 01:25:16 -070028#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <linux/slab.h>
30#include <linux/vmalloc.h>
31#include <linux/elf.h>
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +040032#include <linux/proc_fs.h>
Kees Cook2e72d512012-10-16 07:32:07 +103033#include <linux/security.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034#include <linux/seq_file.h>
35#include <linux/syscalls.h>
36#include <linux/fcntl.h>
37#include <linux/rcupdate.h>
Randy.Dunlapc59ede72006-01-11 12:17:46 -080038#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/cpu.h>
40#include <linux/moduleparam.h>
41#include <linux/errno.h>
42#include <linux/err.h>
43#include <linux/vermagic.h>
44#include <linux/notifier.h>
Al Virof6a57032006-10-18 01:47:25 -040045#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070046#include <linux/device.h>
Matt Domschc988d2b2005-06-23 22:05:15 -070047#include <linux/string.h>
Arjan van de Ven97d1f152006-03-23 03:00:24 -080048#include <linux/mutex.h>
Andi Kleend72b3752008-08-30 10:09:00 +020049#include <linux/rculist.h>
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -080050#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070051#include <asm/cacheflush.h>
Michael Ellerman563ec5c2017-07-06 15:35:58 -070052#include <linux/set_memory.h>
Bernd Schmidteb8cdec2009-09-21 17:03:57 -070053#include <asm/mmu_context.h>
Sam Ravnborgb817f6f2006-06-09 21:53:55 +020054#include <linux/license.h>
Christoph Lameter6d762392008-02-08 04:18:42 -080055#include <asm/sections.h>
Mathieu Desnoyers97e1c182008-07-18 12:16:16 -040056#include <linux/tracepoint.h>
Steven Rostedt90d595f2008-08-14 15:45:09 -040057#include <linux/ftrace.h>
Jessica Yu7e545d62016-03-16 20:55:39 -040058#include <linux/livepatch.h>
Arjan van de Ven22a9d642009-01-07 08:45:46 -080059#include <linux/async.h>
Tejun Heofbf59bc2009-02-20 16:29:08 +090060#include <linux/percpu.h>
Catalin Marinas4f2294b2009-06-11 13:23:20 +010061#include <linux/kmemleak.h>
Jason Baronbf5438fc2010-09-17 11:09:00 -040062#include <linux/jump_label.h>
matthieu castet84e1c6b2010-11-16 22:35:16 +010063#include <linux/pfn.h>
Alessio Igor Bogani403ed272011-04-20 11:10:52 +020064#include <linux/bsearch.h>
Luis de Bethencourt9d5059c2016-08-02 14:03:47 -070065#include <linux/dynamic_debug.h>
Richard Guy Briggsca86cad2017-02-04 13:10:38 -050066#include <linux/audit.h>
Rusty Russell2f3238a2012-10-22 18:09:41 +103067#include <uapi/linux/module.h>
Rusty Russell106a4ee2012-09-26 10:09:40 +010068#include "module-internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070069
Li Zefan7ead8b82009-08-17 16:56:28 +080070#define CREATE_TRACE_POINTS
71#include <trace/events/module.h>
72
Linus Torvalds1da177e2005-04-16 15:20:36 -070073#ifndef ARCH_SHF_SMALL
74#define ARCH_SHF_SMALL 0
75#endif
76
matthieu castet84e1c6b2010-11-16 22:35:16 +010077/*
78 * Modules' sections will be aligned on page boundaries
79 * to ensure complete separation of code and data, but
Laura Abbott0f5bf6d2017-02-06 16:31:58 -080080 * only when CONFIG_STRICT_MODULE_RWX=y
matthieu castet84e1c6b2010-11-16 22:35:16 +010081 */
Laura Abbott0f5bf6d2017-02-06 16:31:58 -080082#ifdef CONFIG_STRICT_MODULE_RWX
matthieu castet84e1c6b2010-11-16 22:35:16 +010083# define debug_align(X) ALIGN(X, PAGE_SIZE)
84#else
85# define debug_align(X) (X)
86#endif
87
Linus Torvalds1da177e2005-04-16 15:20:36 -070088/* If this is set, the section belongs in the init part of the module */
89#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
90
Rusty Russell75676502010-06-05 11:17:36 -060091/*
92 * Mutex protects:
93 * 1) List of modules (also safely readable with preempt_disable),
94 * 2) module_use links,
95 * 3) module_addr_min/module_addr_max.
Masami Hiramatsue513cc12014-11-10 09:30:29 +103096 * (delete and add uses RCU list operations). */
Tim Abbottc6b37802008-12-05 19:03:59 -050097DEFINE_MUTEX(module_mutex);
98EXPORT_SYMBOL_GPL(module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070099static LIST_HEAD(modules);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930100
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930101#ifdef CONFIG_MODULES_TREE_LOOKUP
102
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930103/*
104 * Use a latched RB-tree for __module_address(); this allows us to use
105 * RCU-sched lookups of the address from any context.
106 *
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930107 * This is conditional on PERF_EVENTS || TRACING because those can really hit
108 * __module_address() hard by doing a lot of stack unwinding; potentially from
109 * NMI context.
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930110 */
111
112static __always_inline unsigned long __mod_tree_val(struct latch_tree_node *n)
113{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030114 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930115
Rusty Russell7523e4d2015-11-26 09:44:08 +1030116 return (unsigned long)layout->base;
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930117}
118
119static __always_inline unsigned long __mod_tree_size(struct latch_tree_node *n)
120{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030121 struct module_layout *layout = container_of(n, struct module_layout, mtn.node);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930122
Rusty Russell7523e4d2015-11-26 09:44:08 +1030123 return (unsigned long)layout->size;
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930124}
125
126static __always_inline bool
127mod_tree_less(struct latch_tree_node *a, struct latch_tree_node *b)
128{
129 return __mod_tree_val(a) < __mod_tree_val(b);
130}
131
132static __always_inline int
133mod_tree_comp(void *key, struct latch_tree_node *n)
134{
135 unsigned long val = (unsigned long)key;
136 unsigned long start, end;
137
138 start = __mod_tree_val(n);
139 if (val < start)
140 return -1;
141
142 end = start + __mod_tree_size(n);
143 if (val >= end)
144 return 1;
145
146 return 0;
147}
148
149static const struct latch_tree_ops mod_tree_ops = {
150 .less = mod_tree_less,
151 .comp = mod_tree_comp,
152};
153
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930154static struct mod_tree_root {
155 struct latch_tree_root root;
156 unsigned long addr_min;
157 unsigned long addr_max;
158} mod_tree __cacheline_aligned = {
159 .addr_min = -1UL,
160};
161
162#define module_addr_min mod_tree.addr_min
163#define module_addr_max mod_tree.addr_max
164
165static noinline void __mod_tree_insert(struct mod_tree_node *node)
166{
167 latch_tree_insert(&node->node, &mod_tree.root, &mod_tree_ops);
168}
169
170static void __mod_tree_remove(struct mod_tree_node *node)
171{
172 latch_tree_erase(&node->node, &mod_tree.root, &mod_tree_ops);
173}
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930174
175/*
176 * These modifications: insert, remove_init and remove; are serialized by the
177 * module_mutex.
178 */
179static void mod_tree_insert(struct module *mod)
180{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030181 mod->core_layout.mtn.mod = mod;
182 mod->init_layout.mtn.mod = mod;
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930183
Rusty Russell7523e4d2015-11-26 09:44:08 +1030184 __mod_tree_insert(&mod->core_layout.mtn);
185 if (mod->init_layout.size)
186 __mod_tree_insert(&mod->init_layout.mtn);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930187}
188
189static void mod_tree_remove_init(struct module *mod)
190{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030191 if (mod->init_layout.size)
192 __mod_tree_remove(&mod->init_layout.mtn);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930193}
194
195static void mod_tree_remove(struct module *mod)
196{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030197 __mod_tree_remove(&mod->core_layout.mtn);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930198 mod_tree_remove_init(mod);
199}
200
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930201static struct module *mod_find(unsigned long addr)
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930202{
203 struct latch_tree_node *ltn;
204
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930205 ltn = latch_tree_find((void *)addr, &mod_tree.root, &mod_tree_ops);
Peter Zijlstra93c2e102015-05-27 11:09:37 +0930206 if (!ltn)
207 return NULL;
208
209 return container_of(ltn, struct mod_tree_node, node)->mod;
210}
211
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930212#else /* MODULES_TREE_LOOKUP */
213
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930214static unsigned long module_addr_min = -1UL, module_addr_max = 0;
215
Peter Zijlstra6c9692e2015-05-27 11:09:37 +0930216static void mod_tree_insert(struct module *mod) { }
217static void mod_tree_remove_init(struct module *mod) { }
218static void mod_tree_remove(struct module *mod) { }
219
220static struct module *mod_find(unsigned long addr)
221{
222 struct module *mod;
223
224 list_for_each_entry_rcu(mod, &modules, list) {
225 if (within_module(addr, mod))
226 return mod;
227 }
228
229 return NULL;
230}
231
232#endif /* MODULES_TREE_LOOKUP */
233
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930234/*
235 * Bounds of module text, for speeding up __module_address.
236 * Protected by module_mutex.
237 */
238static void __mod_update_bounds(void *base, unsigned int size)
239{
240 unsigned long min = (unsigned long)base;
241 unsigned long max = min + size;
242
243 if (min < module_addr_min)
244 module_addr_min = min;
245 if (max > module_addr_max)
246 module_addr_max = max;
247}
248
249static void mod_update_bounds(struct module *mod)
250{
Rusty Russell7523e4d2015-11-26 09:44:08 +1030251 __mod_update_bounds(mod->core_layout.base, mod->core_layout.size);
252 if (mod->init_layout.size)
253 __mod_update_bounds(mod->init_layout.base, mod->init_layout.size);
Peter Zijlstra4f6665462015-05-27 11:09:38 +0930254}
255
Jason Wessel67fc4e02010-05-20 21:04:21 -0500256#ifdef CONFIG_KGDB_KDB
257struct list_head *kdb_modules = &modules; /* kdb needs the list of modules */
258#endif /* CONFIG_KGDB_KDB */
259
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930260static void module_assert_mutex(void)
Rusty Russell106a4ee2012-09-26 10:09:40 +0100261{
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930262 lockdep_assert_held(&module_mutex);
Rusty Russell106a4ee2012-09-26 10:09:40 +0100263}
264
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930265static void module_assert_mutex_or_preempt(void)
266{
267#ifdef CONFIG_LOCKDEP
268 if (unlikely(!debug_locks))
269 return;
Rusty Russell106a4ee2012-09-26 10:09:40 +0100270
Steven Rostedt95025142016-07-19 05:59:24 +0930271 WARN_ON_ONCE(!rcu_read_lock_sched_held() &&
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930272 !lockdep_is_held(&module_mutex));
273#endif
274}
275
Luis R. Rodriguez6727bb92015-05-27 11:09:39 +0930276static bool sig_enforce = IS_ENABLED(CONFIG_MODULE_SIG_FORCE);
Rusty Russell106a4ee2012-09-26 10:09:40 +0100277module_param(sig_enforce, bool_enable_only, 0644);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278
Bruno E. O. Meneguelefda784e2017-10-24 15:37:00 -0200279/*
280 * Export sig_enforce kernel cmdline parameter to allow other subsystems rely
281 * on that instead of directly to CONFIG_MODULE_SIG_FORCE config.
282 */
283bool is_module_sig_enforced(void)
284{
285 return sig_enforce;
286}
287EXPORT_SYMBOL(is_module_sig_enforced);
288
Stephen Rothwell19e45292009-04-14 17:27:18 +1000289/* Block module loading/unloading? */
290int modules_disabled = 0;
Dave Young02608be2012-02-01 10:33:14 +0800291core_param(nomodule, modules_disabled, bint, 0);
Stephen Rothwell19e45292009-04-14 17:27:18 +1000292
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500293/* Waiting for a module to finish initializing? */
294static DECLARE_WAIT_QUEUE_HEAD(module_wq);
295
Alan Sterne041c682006-03-27 01:16:30 -0800296static BLOCKING_NOTIFIER_HEAD(module_notify_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700297
Ionut Alexa6da0b562014-11-10 09:31:29 +1030298int register_module_notifier(struct notifier_block *nb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299{
Alan Sterne041c682006-03-27 01:16:30 -0800300 return blocking_notifier_chain_register(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700301}
302EXPORT_SYMBOL(register_module_notifier);
303
Ionut Alexa6da0b562014-11-10 09:31:29 +1030304int unregister_module_notifier(struct notifier_block *nb)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305{
Alan Sterne041c682006-03-27 01:16:30 -0800306 return blocking_notifier_chain_unregister(&module_notify_list, nb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307}
308EXPORT_SYMBOL(unregister_module_notifier);
309
Rusty Russelleded41c2010-08-05 12:59:07 -0600310struct load_info {
Luis R. Rodriguez96b5b192017-06-28 18:32:31 -0700311 const char *name;
Jessica Yu81a0abd2018-06-22 13:59:29 +0200312 /* pointer to module in temporary copy, freed at end of load_module() */
313 struct module *mod;
Rusty Russelleded41c2010-08-05 12:59:07 -0600314 Elf_Ehdr *hdr;
315 unsigned long len;
316 Elf_Shdr *sechdrs;
Rusty Russell6526c532010-08-05 12:59:10 -0600317 char *secstrings, *strtab;
Rusty Russelld9131882010-08-05 12:59:08 -0600318 unsigned long symoffs, stroffs;
Rusty Russell811d66a2010-08-05 12:59:12 -0600319 struct _ddebug *debug;
320 unsigned int num_debug;
Rusty Russell106a4ee2012-09-26 10:09:40 +0100321 bool sig_ok;
Rusty Russell82440622016-02-03 16:55:26 +1030322#ifdef CONFIG_KALLSYMS
323 unsigned long mod_kallsyms_init_off;
324#endif
Rusty Russelleded41c2010-08-05 12:59:07 -0600325 struct {
326 unsigned int sym, str, mod, vers, info, pcpu;
327 } index;
328};
329
Miroslav Benes71d9f502016-11-16 16:45:48 +0100330/*
331 * We require a truly strong try_module_get(): 0 means success.
332 * Otherwise an error is returned due to ongoing or failed
333 * initialization etc.
334 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335static inline int strong_try_module_get(struct module *mod)
336{
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030337 BUG_ON(mod && mod->state == MODULE_STATE_UNFORMED);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 if (mod && mod->state == MODULE_STATE_COMING)
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500339 return -EBUSY;
340 if (try_module_get(mod))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341 return 0;
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500342 else
343 return -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344}
345
Rusty Russell373d4d02013-01-21 17:17:39 +1030346static inline void add_taint_module(struct module *mod, unsigned flag,
347 enum lockdep_ok lockdep_ok)
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700348{
Rusty Russell373d4d02013-01-21 17:17:39 +1030349 add_taint(flag, lockdep_ok);
Petr Mladek7fd83292016-09-21 13:47:22 +0200350 set_bit(flag, &mod->taints);
Florin Malitafa3ba2e82006-10-11 01:21:48 -0700351}
352
Robert P. J. Day02a3e592007-05-09 07:26:28 +0200353/*
354 * A thread that wants to hold a reference to a module only while it
355 * is running can call this to safely exit. nfsd and lockd use this.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 */
Jiri Kosinabf262dc2016-04-12 05:02:09 +0930357void __noreturn __module_put_and_exit(struct module *mod, long code)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
359 module_put(mod);
360 do_exit(code);
361}
362EXPORT_SYMBOL(__module_put_and_exit);
Daniel Walker22a8bde2007-10-18 03:06:07 -0700363
Linus Torvalds1da177e2005-04-16 15:20:36 -0700364/* Find a module section: 0 means not found. */
Rusty Russell49668682010-08-05 12:59:10 -0600365static unsigned int find_sec(const struct load_info *info, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700366{
367 unsigned int i;
368
Rusty Russell49668682010-08-05 12:59:10 -0600369 for (i = 1; i < info->hdr->e_shnum; i++) {
370 Elf_Shdr *shdr = &info->sechdrs[i];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700371 /* Alloc bit cleared means "ignore it." */
Rusty Russell49668682010-08-05 12:59:10 -0600372 if ((shdr->sh_flags & SHF_ALLOC)
373 && strcmp(info->secstrings + shdr->sh_name, name) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 return i;
Rusty Russell49668682010-08-05 12:59:10 -0600375 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700376 return 0;
377}
378
Rusty Russell5e458cc2008-10-22 10:00:13 -0500379/* Find a module section, or NULL. */
Rusty Russell49668682010-08-05 12:59:10 -0600380static void *section_addr(const struct load_info *info, const char *name)
Rusty Russell5e458cc2008-10-22 10:00:13 -0500381{
382 /* Section 0 has sh_addr 0. */
Rusty Russell49668682010-08-05 12:59:10 -0600383 return (void *)info->sechdrs[find_sec(info, name)].sh_addr;
Rusty Russell5e458cc2008-10-22 10:00:13 -0500384}
385
386/* Find a module section, or NULL. Fill in number of "objects" in section. */
Rusty Russell49668682010-08-05 12:59:10 -0600387static void *section_objs(const struct load_info *info,
Rusty Russell5e458cc2008-10-22 10:00:13 -0500388 const char *name,
389 size_t object_size,
390 unsigned int *num)
391{
Rusty Russell49668682010-08-05 12:59:10 -0600392 unsigned int sec = find_sec(info, name);
Rusty Russell5e458cc2008-10-22 10:00:13 -0500393
394 /* Section 0 has sh_addr 0 and sh_size 0. */
Rusty Russell49668682010-08-05 12:59:10 -0600395 *num = info->sechdrs[sec].sh_size / object_size;
396 return (void *)info->sechdrs[sec].sh_addr;
Rusty Russell5e458cc2008-10-22 10:00:13 -0500397}
398
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399/* Provided by the linker */
400extern const struct kernel_symbol __start___ksymtab[];
401extern const struct kernel_symbol __stop___ksymtab[];
402extern const struct kernel_symbol __start___ksymtab_gpl[];
403extern const struct kernel_symbol __stop___ksymtab_gpl[];
Greg Kroah-Hartman9f28bb72006-03-20 13:17:13 -0800404extern const struct kernel_symbol __start___ksymtab_gpl_future[];
405extern const struct kernel_symbol __stop___ksymtab_gpl_future[];
Ard Biesheuvel71810db2017-02-03 09:54:06 +0000406extern const s32 __start___kcrctab[];
407extern const s32 __start___kcrctab_gpl[];
408extern const s32 __start___kcrctab_gpl_future[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500409#ifdef CONFIG_UNUSED_SYMBOLS
410extern const struct kernel_symbol __start___ksymtab_unused[];
411extern const struct kernel_symbol __stop___ksymtab_unused[];
412extern const struct kernel_symbol __start___ksymtab_unused_gpl[];
413extern const struct kernel_symbol __stop___ksymtab_unused_gpl[];
Ard Biesheuvel71810db2017-02-03 09:54:06 +0000414extern const s32 __start___kcrctab_unused[];
415extern const s32 __start___kcrctab_unused_gpl[];
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500416#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417
418#ifndef CONFIG_MODVERSIONS
419#define symversion(base, idx) NULL
420#else
Andrew Mortonf83ca9f2006-03-28 01:56:20 -0800421#define symversion(base, idx) ((base != NULL) ? ((base) + (idx)) : NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422#endif
423
Rusty Russelldafd0942008-07-22 19:24:25 -0500424static bool each_symbol_in_section(const struct symsearch *arr,
425 unsigned int arrsize,
426 struct module *owner,
427 bool (*fn)(const struct symsearch *syms,
428 struct module *owner,
Rusty Russellde4d8d52011-04-19 21:49:58 +0200429 void *data),
Rusty Russelldafd0942008-07-22 19:24:25 -0500430 void *data)
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100431{
Rusty Russellde4d8d52011-04-19 21:49:58 +0200432 unsigned int j;
Rusty Russelldafd0942008-07-22 19:24:25 -0500433
434 for (j = 0; j < arrsize; j++) {
Rusty Russellde4d8d52011-04-19 21:49:58 +0200435 if (fn(&arr[j], owner, data))
436 return true;
Rusty Russelldafd0942008-07-22 19:24:25 -0500437 }
438
439 return false;
Sam Ravnborg3fd68052006-02-08 21:16:45 +0100440}
441
Rusty Russelldafd0942008-07-22 19:24:25 -0500442/* Returns true as soon as fn returns true, otherwise false. */
Rusty Russellde4d8d52011-04-19 21:49:58 +0200443bool each_symbol_section(bool (*fn)(const struct symsearch *arr,
444 struct module *owner,
445 void *data),
446 void *data)
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700447{
Rusty Russelldafd0942008-07-22 19:24:25 -0500448 struct module *mod;
Linus Torvalds44032e62010-08-05 12:59:05 -0600449 static const struct symsearch arr[] = {
Rusty Russelldafd0942008-07-22 19:24:25 -0500450 { __start___ksymtab, __stop___ksymtab, __start___kcrctab,
451 NOT_GPL_ONLY, false },
452 { __start___ksymtab_gpl, __stop___ksymtab_gpl,
453 __start___kcrctab_gpl,
454 GPL_ONLY, false },
455 { __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
456 __start___kcrctab_gpl_future,
457 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500458#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500459 { __start___ksymtab_unused, __stop___ksymtab_unused,
460 __start___kcrctab_unused,
461 NOT_GPL_ONLY, true },
462 { __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
463 __start___kcrctab_unused_gpl,
464 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500465#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500466 };
467
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930468 module_assert_mutex_or_preempt();
469
Rusty Russelldafd0942008-07-22 19:24:25 -0500470 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), NULL, fn, data))
471 return true;
472
Andi Kleend72b3752008-08-30 10:09:00 +0200473 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russelldafd0942008-07-22 19:24:25 -0500474 struct symsearch arr[] = {
475 { mod->syms, mod->syms + mod->num_syms, mod->crcs,
476 NOT_GPL_ONLY, false },
477 { mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
478 mod->gpl_crcs,
479 GPL_ONLY, false },
480 { mod->gpl_future_syms,
481 mod->gpl_future_syms + mod->num_gpl_future_syms,
482 mod->gpl_future_crcs,
483 WILL_BE_GPL_ONLY, false },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500484#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500485 { mod->unused_syms,
486 mod->unused_syms + mod->num_unused_syms,
487 mod->unused_crcs,
488 NOT_GPL_ONLY, true },
489 { mod->unused_gpl_syms,
490 mod->unused_gpl_syms + mod->num_unused_gpl_syms,
491 mod->unused_gpl_crcs,
492 GPL_ONLY, true },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500493#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500494 };
495
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030496 if (mod->state == MODULE_STATE_UNFORMED)
497 continue;
498
Rusty Russelldafd0942008-07-22 19:24:25 -0500499 if (each_symbol_in_section(arr, ARRAY_SIZE(arr), mod, fn, data))
500 return true;
501 }
502 return false;
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700503}
Rusty Russellde4d8d52011-04-19 21:49:58 +0200504EXPORT_SYMBOL_GPL(each_symbol_section);
Arjan van de Venf71d20e2006-06-28 04:26:45 -0700505
Rusty Russelldafd0942008-07-22 19:24:25 -0500506struct find_symbol_arg {
507 /* Input */
508 const char *name;
509 bool gplok;
510 bool warn;
511
512 /* Output */
513 struct module *owner;
Ard Biesheuvel71810db2017-02-03 09:54:06 +0000514 const s32 *crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500515 const struct kernel_symbol *sym;
Rusty Russelldafd0942008-07-22 19:24:25 -0500516};
517
Rusty Russellde4d8d52011-04-19 21:49:58 +0200518static bool check_symbol(const struct symsearch *syms,
519 struct module *owner,
520 unsigned int symnum, void *data)
Rusty Russellad9546c2008-05-01 21:14:59 -0500521{
Rusty Russelldafd0942008-07-22 19:24:25 -0500522 struct find_symbol_arg *fsa = data;
523
Rusty Russelldafd0942008-07-22 19:24:25 -0500524 if (!fsa->gplok) {
525 if (syms->licence == GPL_ONLY)
526 return false;
527 if (syms->licence == WILL_BE_GPL_ONLY && fsa->warn) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800528 pr_warn("Symbol %s is being used by a non-GPL module, "
529 "which will not be allowed in the future\n",
530 fsa->name);
Rusty Russelldafd0942008-07-22 19:24:25 -0500531 }
532 }
533
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500534#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russelldafd0942008-07-22 19:24:25 -0500535 if (syms->unused && fsa->warn) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800536 pr_warn("Symbol %s is marked as UNUSED, however this module is "
537 "using it.\n", fsa->name);
538 pr_warn("This symbol will go away in the future.\n");
Yannick Guerrini7b63c3a2015-03-24 12:31:40 +1030539 pr_warn("Please evaluate if this is the right api to use and "
540 "if it really is, submit a report to the linux kernel "
541 "mailing list together with submitting your code for "
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800542 "inclusion.\n");
Rusty Russellad9546c2008-05-01 21:14:59 -0500543 }
Denys Vlasenkof7f5b672008-07-22 19:24:26 -0500544#endif
Rusty Russelldafd0942008-07-22 19:24:25 -0500545
546 fsa->owner = owner;
547 fsa->crc = symversion(syms->crcs, symnum);
Tim Abbott414fd312008-12-05 19:03:56 -0500548 fsa->sym = &syms->start[symnum];
Rusty Russellad9546c2008-05-01 21:14:59 -0500549 return true;
550}
551
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200552static int cmp_name(const void *va, const void *vb)
553{
554 const char *a;
555 const struct kernel_symbol *b;
556 a = va; b = vb;
557 return strcmp(a, b->name);
558}
559
Rusty Russellde4d8d52011-04-19 21:49:58 +0200560static bool find_symbol_in_section(const struct symsearch *syms,
561 struct module *owner,
562 void *data)
563{
564 struct find_symbol_arg *fsa = data;
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200565 struct kernel_symbol *sym;
Rusty Russellde4d8d52011-04-19 21:49:58 +0200566
Alessio Igor Bogani403ed272011-04-20 11:10:52 +0200567 sym = bsearch(fsa->name, syms->start, syms->stop - syms->start,
568 sizeof(struct kernel_symbol), cmp_name);
569
570 if (sym != NULL && check_symbol(syms, owner, sym - syms->start, data))
571 return true;
572
Rusty Russellde4d8d52011-04-19 21:49:58 +0200573 return false;
574}
575
Tim Abbott414fd312008-12-05 19:03:56 -0500576/* Find a symbol and return it, along with, (optional) crc and
Rusty Russell75676502010-06-05 11:17:36 -0600577 * (optional) module which owns it. Needs preempt disabled or module_mutex. */
Tim Abbottc6b37802008-12-05 19:03:59 -0500578const struct kernel_symbol *find_symbol(const char *name,
579 struct module **owner,
Ard Biesheuvel71810db2017-02-03 09:54:06 +0000580 const s32 **crc,
Tim Abbottc6b37802008-12-05 19:03:59 -0500581 bool gplok,
582 bool warn)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583{
Rusty Russelldafd0942008-07-22 19:24:25 -0500584 struct find_symbol_arg fsa;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585
Rusty Russelldafd0942008-07-22 19:24:25 -0500586 fsa.name = name;
587 fsa.gplok = gplok;
588 fsa.warn = warn;
589
Rusty Russellde4d8d52011-04-19 21:49:58 +0200590 if (each_symbol_section(find_symbol_in_section, &fsa)) {
Rusty Russellad9546c2008-05-01 21:14:59 -0500591 if (owner)
Rusty Russelldafd0942008-07-22 19:24:25 -0500592 *owner = fsa.owner;
593 if (crc)
594 *crc = fsa.crc;
Tim Abbott414fd312008-12-05 19:03:56 -0500595 return fsa.sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 }
Rusty Russellad9546c2008-05-01 21:14:59 -0500597
Jim Cromie5e124162011-12-06 12:11:31 -0700598 pr_debug("Failed to find symbol %s\n", name);
Tim Abbott414fd312008-12-05 19:03:56 -0500599 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600}
Tim Abbottc6b37802008-12-05 19:03:59 -0500601EXPORT_SYMBOL_GPL(find_symbol);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602
Rusty Russellfe0d34d2015-07-29 05:52:14 +0930603/*
604 * Search for module by name: must hold module_mutex (or preempt disabled
605 * for read-only access).
606 */
Mathias Krause4f6de4d52013-07-02 15:35:11 +0930607static struct module *find_module_all(const char *name, size_t len,
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030608 bool even_unformed)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609{
610 struct module *mod;
611
Rusty Russellfe0d34d2015-07-29 05:52:14 +0930612 module_assert_mutex_or_preempt();
Peter Zijlstra0be964b2015-05-27 11:09:35 +0930613
Luis R. Rodriguez93437352017-05-26 14:12:25 -0700614 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030615 if (!even_unformed && mod->state == MODULE_STATE_UNFORMED)
616 continue;
Mathias Krause4f6de4d52013-07-02 15:35:11 +0930617 if (strlen(mod->name) == len && !memcmp(mod->name, name, len))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 return mod;
619 }
620 return NULL;
621}
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030622
623struct module *find_module(const char *name)
624{
Rusty Russellfe0d34d2015-07-29 05:52:14 +0930625 module_assert_mutex();
Mathias Krause4f6de4d52013-07-02 15:35:11 +0930626 return find_module_all(name, strlen(name), false);
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030627}
Tim Abbottc6b37802008-12-05 19:03:59 -0500628EXPORT_SYMBOL_GPL(find_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700629
630#ifdef CONFIG_SMP
Tejun Heofbf59bc2009-02-20 16:29:08 +0900631
Tejun Heo259354d2010-03-10 18:56:10 +0900632static inline void __percpu *mod_percpu(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900633{
Tejun Heo259354d2010-03-10 18:56:10 +0900634 return mod->percpu;
635}
Tejun Heofbf59bc2009-02-20 16:29:08 +0900636
Rusty Russell9eb76d72013-07-03 10:06:29 +0930637static int percpu_modalloc(struct module *mod, struct load_info *info)
Tejun Heo259354d2010-03-10 18:56:10 +0900638{
Rusty Russell9eb76d72013-07-03 10:06:29 +0930639 Elf_Shdr *pcpusec = &info->sechdrs[info->index.pcpu];
640 unsigned long align = pcpusec->sh_addralign;
641
642 if (!pcpusec->sh_size)
643 return 0;
644
Tejun Heofbf59bc2009-02-20 16:29:08 +0900645 if (align > PAGE_SIZE) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800646 pr_warn("%s: per-cpu alignment %li > %li\n",
647 mod->name, align, PAGE_SIZE);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900648 align = PAGE_SIZE;
649 }
650
Rusty Russell9eb76d72013-07-03 10:06:29 +0930651 mod->percpu = __alloc_reserved_percpu(pcpusec->sh_size, align);
Tejun Heo259354d2010-03-10 18:56:10 +0900652 if (!mod->percpu) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -0800653 pr_warn("%s: Could not allocate %lu bytes percpu data\n",
654 mod->name, (unsigned long)pcpusec->sh_size);
Tejun Heo259354d2010-03-10 18:56:10 +0900655 return -ENOMEM;
656 }
Rusty Russell9eb76d72013-07-03 10:06:29 +0930657 mod->percpu_size = pcpusec->sh_size;
Tejun Heo259354d2010-03-10 18:56:10 +0900658 return 0;
Tejun Heofbf59bc2009-02-20 16:29:08 +0900659}
660
Tejun Heo259354d2010-03-10 18:56:10 +0900661static void percpu_modfree(struct module *mod)
Tejun Heofbf59bc2009-02-20 16:29:08 +0900662{
Tejun Heo259354d2010-03-10 18:56:10 +0900663 free_percpu(mod->percpu);
Tejun Heofbf59bc2009-02-20 16:29:08 +0900664}
665
Rusty Russell49668682010-08-05 12:59:10 -0600666static unsigned int find_pcpusec(struct load_info *info)
Tejun Heo6b588c12009-02-20 16:29:07 +0900667{
Rusty Russell49668682010-08-05 12:59:10 -0600668 return find_sec(info, ".data..percpu");
Tejun Heo6b588c12009-02-20 16:29:07 +0900669}
670
Tejun Heo259354d2010-03-10 18:56:10 +0900671static void percpu_modcopy(struct module *mod,
672 const void *from, unsigned long size)
Tejun Heo6b588c12009-02-20 16:29:07 +0900673{
674 int cpu;
675
676 for_each_possible_cpu(cpu)
Tejun Heo259354d2010-03-10 18:56:10 +0900677 memcpy(per_cpu_ptr(mod->percpu, cpu), from, size);
Tejun Heo6b588c12009-02-20 16:29:07 +0900678}
679
Thomas Gleixner383776f2017-02-27 15:37:36 +0100680bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
Tejun Heo10fad5e2010-03-10 18:57:54 +0900681{
682 struct module *mod;
683 unsigned int cpu;
684
685 preempt_disable();
686
687 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +1030688 if (mod->state == MODULE_STATE_UNFORMED)
689 continue;
Tejun Heo10fad5e2010-03-10 18:57:54 +0900690 if (!mod->percpu_size)
691 continue;
692 for_each_possible_cpu(cpu) {
693 void *start = per_cpu_ptr(mod->percpu, cpu);
Thomas Gleixner383776f2017-02-27 15:37:36 +0100694 void *va = (void *)addr;
Tejun Heo10fad5e2010-03-10 18:57:54 +0900695
Thomas Gleixner383776f2017-02-27 15:37:36 +0100696 if (va >= start && va < start + mod->percpu_size) {
Peter Zijlstra8ce371f2017-03-20 12:26:55 +0100697 if (can_addr) {
Thomas Gleixner383776f2017-02-27 15:37:36 +0100698 *can_addr = (unsigned long) (va - start);
Peter Zijlstra8ce371f2017-03-20 12:26:55 +0100699 *can_addr += (unsigned long)
700 per_cpu_ptr(mod->percpu,
701 get_boot_cpu_id());
702 }
Tejun Heo10fad5e2010-03-10 18:57:54 +0900703 preempt_enable();
704 return true;
705 }
706 }
707 }
708
709 preempt_enable();
710 return false;
Daniel Walker22a8bde2007-10-18 03:06:07 -0700711}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712
Thomas Gleixner383776f2017-02-27 15:37:36 +0100713/**
714 * is_module_percpu_address - test whether address is from module static percpu
715 * @addr: address to test
716 *
717 * Test whether @addr belongs to module static percpu area.
718 *
719 * RETURNS:
720 * %true if @addr is from module static percpu area
721 */
722bool is_module_percpu_address(unsigned long addr)
723{
724 return __is_module_percpu_address(addr, NULL);
725}
726
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727#else /* ... !CONFIG_SMP */
Tejun Heo6b588c12009-02-20 16:29:07 +0900728
Tejun Heo259354d2010-03-10 18:56:10 +0900729static inline void __percpu *mod_percpu(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730{
731 return NULL;
732}
Rusty Russell9eb76d72013-07-03 10:06:29 +0930733static int percpu_modalloc(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734{
Rusty Russell9eb76d72013-07-03 10:06:29 +0930735 /* UP modules shouldn't have this section: ENOMEM isn't quite right */
736 if (info->sechdrs[info->index.pcpu].sh_size != 0)
737 return -ENOMEM;
738 return 0;
Tejun Heo259354d2010-03-10 18:56:10 +0900739}
740static inline void percpu_modfree(struct module *mod)
741{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742}
Rusty Russell49668682010-08-05 12:59:10 -0600743static unsigned int find_pcpusec(struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744{
745 return 0;
746}
Tejun Heo259354d2010-03-10 18:56:10 +0900747static inline void percpu_modcopy(struct module *mod,
748 const void *from, unsigned long size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749{
750 /* pcpusec should be 0, and size of that section should be 0. */
751 BUG_ON(size != 0);
752}
Tejun Heo10fad5e2010-03-10 18:57:54 +0900753bool is_module_percpu_address(unsigned long addr)
754{
755 return false;
756}
Tejun Heo6b588c12009-02-20 16:29:07 +0900757
Thomas Gleixner383776f2017-02-27 15:37:36 +0100758bool __is_module_percpu_address(unsigned long addr, unsigned long *can_addr)
759{
760 return false;
761}
762
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763#endif /* CONFIG_SMP */
764
Matt Domschc988d2b2005-06-23 22:05:15 -0700765#define MODINFO_ATTR(field) \
766static void setup_modinfo_##field(struct module *mod, const char *s) \
767{ \
768 mod->field = kstrdup(s, GFP_KERNEL); \
769} \
770static ssize_t show_modinfo_##field(struct module_attribute *mattr, \
Kay Sievers4befb022011-07-24 22:06:04 +0930771 struct module_kobject *mk, char *buffer) \
Matt Domschc988d2b2005-06-23 22:05:15 -0700772{ \
Chen Gangcc56ded2013-08-20 15:34:21 +0930773 return scnprintf(buffer, PAGE_SIZE, "%s\n", mk->mod->field); \
Matt Domschc988d2b2005-06-23 22:05:15 -0700774} \
775static int modinfo_##field##_exists(struct module *mod) \
776{ \
777 return mod->field != NULL; \
778} \
779static void free_modinfo_##field(struct module *mod) \
780{ \
Daniel Walker22a8bde2007-10-18 03:06:07 -0700781 kfree(mod->field); \
782 mod->field = NULL; \
Matt Domschc988d2b2005-06-23 22:05:15 -0700783} \
784static struct module_attribute modinfo_##field = { \
Tejun Heo7b595752007-06-14 03:45:17 +0900785 .attr = { .name = __stringify(field), .mode = 0444 }, \
Matt Domschc988d2b2005-06-23 22:05:15 -0700786 .show = show_modinfo_##field, \
787 .setup = setup_modinfo_##field, \
788 .test = modinfo_##field##_exists, \
789 .free = free_modinfo_##field, \
790};
791
792MODINFO_ATTR(version);
793MODINFO_ATTR(srcversion);
794
Arjan van de Vene14af7e2008-01-25 21:08:33 +0100795static char last_unloaded_module[MODULE_NAME_LEN+1];
796
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -0800797#ifdef CONFIG_MODULE_UNLOAD
Steven Rostedteb0c5372010-03-29 14:25:18 -0400798
799EXPORT_TRACEPOINT_SYMBOL(module_get);
800
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030801/* MODULE_REF_BASE is the base reference count by kmodule loader. */
802#define MODULE_REF_BASE 1
803
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804/* Init the unload section of the module. */
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600805static int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700806{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030807 /*
808 * Initialize reference counter to MODULE_REF_BASE.
809 * refcnt == 0 means module is going.
810 */
811 atomic_set(&mod->refcnt, MODULE_REF_BASE);
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600812
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700813 INIT_LIST_HEAD(&mod->source_list);
814 INIT_LIST_HEAD(&mod->target_list);
Christoph Lametere1783a22010-01-05 15:34:50 +0900815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 /* Hold reference count during initialization. */
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030817 atomic_inc(&mod->refcnt);
Rusty Russell9f85a4b2010-08-05 12:59:04 -0600818
819 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820}
821
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822/* Does a already use b? */
823static int already_uses(struct module *a, struct module *b)
824{
825 struct module_use *use;
826
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700827 list_for_each_entry(use, &b->source_list, source_list) {
828 if (use->source == a) {
Jim Cromie5e124162011-12-06 12:11:31 -0700829 pr_debug("%s uses %s!\n", a->name, b->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830 return 1;
831 }
832 }
Jim Cromie5e124162011-12-06 12:11:31 -0700833 pr_debug("%s does not use %s!\n", a->name, b->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700834 return 0;
835}
836
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700837/*
838 * Module a uses b
839 * - we add 'a' as a "source", 'b' as a "target" of module use
840 * - the module_use is added to the list of 'b' sources (so
841 * 'b' can walk the list to see who sourced them), and of 'a'
842 * targets (so 'a' can see what modules it targets).
843 */
844static int add_module_usage(struct module *a, struct module *b)
845{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700846 struct module_use *use;
847
Jim Cromie5e124162011-12-06 12:11:31 -0700848 pr_debug("Allocating new usage for %s.\n", a->name);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700849 use = kmalloc(sizeof(*use), GFP_ATOMIC);
Markus Elfring9ad04572017-10-06 16:27:26 +0200850 if (!use)
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700851 return -ENOMEM;
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700852
853 use->source = a;
854 use->target = b;
855 list_add(&use->source_list, &b->source_list);
856 list_add(&use->target_list, &a->target_list);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700857 return 0;
858}
859
Rusty Russell75676502010-06-05 11:17:36 -0600860/* Module a uses b: caller needs module_mutex() */
Rusty Russell9bea7f22010-06-05 11:17:37 -0600861int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862{
Rusty Russellc8e21ce2010-06-05 11:17:35 -0600863 int err;
Kay Sievers270a6c42007-01-18 13:26:15 +0100864
Rusty Russell9bea7f22010-06-05 11:17:37 -0600865 if (b == NULL || already_uses(a, b))
Linus Torvalds218ce732010-05-25 16:48:30 -0700866 return 0;
Linus Torvalds218ce732010-05-25 16:48:30 -0700867
Rusty Russell9bea7f22010-06-05 11:17:37 -0600868 /* If module isn't available, we fail. */
869 err = strong_try_module_get(b);
Rusty Russellc9a3ba52008-01-29 17:13:18 -0500870 if (err)
Rusty Russell9bea7f22010-06-05 11:17:37 -0600871 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700872
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700873 err = add_module_usage(a, b);
874 if (err) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 module_put(b);
Rusty Russell9bea7f22010-06-05 11:17:37 -0600876 return err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 }
Rusty Russell9bea7f22010-06-05 11:17:37 -0600878 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879}
Rusty Russell9bea7f22010-06-05 11:17:37 -0600880EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881
882/* Clear the unload stuff of the module. */
883static void module_unload_free(struct module *mod)
884{
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700885 struct module_use *use, *tmp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886
Rusty Russell75676502010-06-05 11:17:36 -0600887 mutex_lock(&module_mutex);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700888 list_for_each_entry_safe(use, tmp, &mod->target_list, target_list) {
889 struct module *i = use->target;
Jim Cromie5e124162011-12-06 12:11:31 -0700890 pr_debug("%s unusing %s\n", mod->name, i->name);
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700891 module_put(i);
892 list_del(&use->source_list);
893 list_del(&use->target_list);
894 kfree(use);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 }
Rusty Russell75676502010-06-05 11:17:36 -0600896 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897}
898
899#ifdef CONFIG_MODULE_FORCE_UNLOAD
Akinobu Mitafb169792006-01-08 01:04:29 -0800900static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901{
902 int ret = (flags & O_TRUNC);
903 if (ret)
Rusty Russell373d4d02013-01-21 17:17:39 +1030904 add_taint(TAINT_FORCED_RMMOD, LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 return ret;
906}
907#else
Akinobu Mitafb169792006-01-08 01:04:29 -0800908static inline int try_force_unload(unsigned int flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909{
910 return 0;
911}
912#endif /* CONFIG_MODULE_FORCE_UNLOAD */
913
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030914/* Try to release refcount of module, 0 means success. */
915static int try_release_module_ref(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030917 int ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030919 /* Try to decrement refcnt which we set at loading */
920 ret = atomic_sub_return(MODULE_REF_BASE, &mod->refcnt);
921 BUG_ON(ret < 0);
922 if (ret)
923 /* Someone can put this right now, recover with checking */
924 ret = atomic_add_unless(&mod->refcnt, MODULE_REF_BASE, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030926 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927}
928
929static int try_stop_module(struct module *mod, int flags, int *forced)
930{
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030931 /* If it's not unused, quit unless we're forcing. */
932 if (try_release_module_ref(mod) != 0) {
933 *forced = try_force_unload(flags);
934 if (!(*forced))
935 return -EWOULDBLOCK;
936 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700937
Masami Hiramatsue513cc12014-11-10 09:30:29 +1030938 /* Mark it as dying. */
939 mod->state = MODULE_STATE_GOING;
940
941 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942}
943
Rusty Russelld5db1392015-01-22 11:13:14 +1030944/**
945 * module_refcount - return the refcount or -1 if unloading
946 *
947 * @mod: the module we're checking
948 *
949 * Returns:
950 * -1 if the module is in the process of unloading
951 * otherwise the number of references in the kernel to the module
952 */
953int module_refcount(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954{
Rusty Russelld5db1392015-01-22 11:13:14 +1030955 return atomic_read(&mod->refcnt) - MODULE_REF_BASE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956}
957EXPORT_SYMBOL(module_refcount);
958
959/* This exists whether we can unload or not */
960static void free_module(struct module *mod);
961
Heiko Carstens17da2bd2009-01-14 14:14:10 +0100962SYSCALL_DEFINE2(delete_module, const char __user *, name_user,
963 unsigned int, flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964{
965 struct module *mod;
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800966 char name[MODULE_NAME_LEN];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967 int ret, forced = 0;
968
Kees Cook3d433212009-04-02 15:49:29 -0700969 if (!capable(CAP_SYS_MODULE) || modules_disabled)
Greg Kroah-Hartmandfff0a02007-02-23 14:54:57 -0800970 return -EPERM;
971
972 if (strncpy_from_user(name, name_user, MODULE_NAME_LEN-1) < 0)
973 return -EFAULT;
974 name[MODULE_NAME_LEN-1] = '\0';
975
Richard Guy Briggsf6276ac2017-05-02 10:16:04 -0400976 audit_log_kern_module(name);
977
Tejun Heo3fc1f1e2010-05-06 18:49:20 +0200978 if (mutex_lock_interruptible(&module_mutex) != 0)
979 return -EINTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700980
981 mod = find_module(name);
982 if (!mod) {
983 ret = -ENOENT;
984 goto out;
985 }
986
Linus Torvalds2c02dfe2010-05-31 12:19:37 -0700987 if (!list_empty(&mod->source_list)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700988 /* Other modules depend on us: get rid of them first. */
989 ret = -EWOULDBLOCK;
990 goto out;
991 }
992
993 /* Doing init or already dying? */
994 if (mod->state != MODULE_STATE_LIVE) {
Rusty Russell3f2b9c92013-09-17 05:48:51 +0930995 /* FIXME: if (force), slam module count damn the torpedoes */
Jim Cromie5e124162011-12-06 12:11:31 -0700996 pr_debug("%s already dying\n", mod->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700997 ret = -EBUSY;
998 goto out;
999 }
1000
1001 /* If it has an init func, it must have an exit func to unload */
Rusty Russellaf49d922007-10-16 23:26:27 -07001002 if (mod->init && !mod->exit) {
Akinobu Mitafb169792006-01-08 01:04:29 -08001003 forced = try_force_unload(flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004 if (!forced) {
1005 /* This module can't be removed */
1006 ret = -EBUSY;
1007 goto out;
1008 }
1009 }
1010
Linus Torvalds1da177e2005-04-16 15:20:36 -07001011 /* Stop the machine so refcounts can't move and disable module. */
1012 ret = try_stop_module(mod, flags, &forced);
1013 if (ret != 0)
1014 goto out;
1015
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02001016 mutex_unlock(&module_mutex);
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001017 /* Final destruction now no one is using it. */
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02001018 if (mod->exit != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019 mod->exit();
Peter Oberparleiterdf4b5652008-04-21 14:34:31 +02001020 blocking_notifier_call_chain(&module_notify_list,
1021 MODULE_STATE_GOING, mod);
Jessica Yu7e545d62016-03-16 20:55:39 -04001022 klp_module_going(mod);
Jessica Yu7dcd1822016-02-16 17:32:33 -05001023 ftrace_release_mod(mod);
1024
Arjan van de Ven22a9d642009-01-07 08:45:46 -08001025 async_synchronize_full();
Rusty Russell75676502010-06-05 11:17:36 -06001026
Arjan van de Vene14af7e2008-01-25 21:08:33 +01001027 /* Store the name of the last unloaded module for diagnostic purposes */
Rusty Russellefa53452008-01-29 17:13:20 -05001028 strlcpy(last_unloaded_module, mod->name, sizeof(last_unloaded_module));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029
Rusty Russell75676502010-06-05 11:17:36 -06001030 free_module(mod);
1031 return 0;
1032out:
Ashutosh Naik6389a382006-03-23 03:00:46 -08001033 mutex_unlock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034 return ret;
1035}
1036
Jianjun Kongd1e99d72008-12-08 14:26:29 +08001037static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001038{
1039 struct module_use *use;
1040 int printed_something = 0;
1041
Rusty Russelld5db1392015-01-22 11:13:14 +10301042 seq_printf(m, " %i ", module_refcount(mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001043
Ionut Alexa6da0b562014-11-10 09:31:29 +10301044 /*
1045 * Always include a trailing , so userspace can differentiate
1046 * between this and the old multi-field proc format.
1047 */
Linus Torvalds2c02dfe2010-05-31 12:19:37 -07001048 list_for_each_entry(use, &mod->source_list, source_list) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049 printed_something = 1;
Linus Torvalds2c02dfe2010-05-31 12:19:37 -07001050 seq_printf(m, "%s,", use->source->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 }
1052
Linus Torvalds1da177e2005-04-16 15:20:36 -07001053 if (mod->init != NULL && mod->exit == NULL) {
1054 printed_something = 1;
Ionut Alexa6da0b562014-11-10 09:31:29 +10301055 seq_puts(m, "[permanent],");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056 }
1057
1058 if (!printed_something)
Ionut Alexa6da0b562014-11-10 09:31:29 +10301059 seq_puts(m, "-");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060}
1061
1062void __symbol_put(const char *symbol)
1063{
1064 struct module *owner;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065
Rusty Russell24da1cb2007-07-15 23:41:46 -07001066 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05001067 if (!find_symbol(symbol, &owner, NULL, true, false))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001068 BUG();
1069 module_put(owner);
Rusty Russell24da1cb2007-07-15 23:41:46 -07001070 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071}
1072EXPORT_SYMBOL(__symbol_put);
1073
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301074/* Note this assumes addr is a function, which it currently always is. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075void symbol_put_addr(void *addr)
1076{
Trent Piepho5e376612006-05-15 09:44:06 -07001077 struct module *modaddr;
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301078 unsigned long a = (unsigned long)dereference_function_descriptor(addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301080 if (core_kernel_text(a))
Trent Piepho5e376612006-05-15 09:44:06 -07001081 return;
1082
Peter Zijlstra275d7d42015-08-20 10:34:59 +09301083 /*
1084 * Even though we hold a reference on the module; we still need to
1085 * disable preemption in order to safely traverse the data structure.
1086 */
1087 preempt_disable();
Rusty Russell7d1d16e2009-08-26 22:02:54 +09301088 modaddr = __module_text_address(a);
Rusty Russella6e6abd2009-03-31 13:05:31 -06001089 BUG_ON(!modaddr);
Trent Piepho5e376612006-05-15 09:44:06 -07001090 module_put(modaddr);
Peter Zijlstra275d7d42015-08-20 10:34:59 +09301091 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092}
1093EXPORT_SYMBOL_GPL(symbol_put_addr);
1094
1095static ssize_t show_refcnt(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301096 struct module_kobject *mk, char *buffer)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097{
Rusty Russelld5db1392015-01-22 11:13:14 +10301098 return sprintf(buffer, "%i\n", module_refcount(mk->mod));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099}
1100
Kay Sieverscca3e702012-01-13 09:32:15 +10301101static struct module_attribute modinfo_refcnt =
1102 __ATTR(refcnt, 0444, show_refcnt, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001103
Steven Rostedtd53799b2012-03-26 12:50:52 +10301104void __module_get(struct module *module)
1105{
1106 if (module) {
1107 preempt_disable();
Masami Hiramatsu2f35c412014-11-10 09:29:29 +10301108 atomic_inc(&module->refcnt);
Steven Rostedtd53799b2012-03-26 12:50:52 +10301109 trace_module_get(module, _RET_IP_);
1110 preempt_enable();
1111 }
1112}
1113EXPORT_SYMBOL(__module_get);
1114
1115bool try_module_get(struct module *module)
1116{
1117 bool ret = true;
1118
1119 if (module) {
1120 preempt_disable();
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301121 /* Note: here, we can fail to get a reference */
1122 if (likely(module_is_live(module) &&
1123 atomic_inc_not_zero(&module->refcnt) != 0))
Steven Rostedtd53799b2012-03-26 12:50:52 +10301124 trace_module_get(module, _RET_IP_);
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301125 else
Steven Rostedtd53799b2012-03-26 12:50:52 +10301126 ret = false;
1127
1128 preempt_enable();
1129 }
1130 return ret;
1131}
1132EXPORT_SYMBOL(try_module_get);
1133
Al Virof6a57032006-10-18 01:47:25 -04001134void module_put(struct module *module)
1135{
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301136 int ret;
1137
Al Virof6a57032006-10-18 01:47:25 -04001138 if (module) {
Christoph Lametere1783a22010-01-05 15:34:50 +09001139 preempt_disable();
Masami Hiramatsue513cc12014-11-10 09:30:29 +10301140 ret = atomic_dec_if_positive(&module->refcnt);
1141 WARN_ON(ret < 0); /* Failed to put refcount */
Li Zefanae832d12010-03-24 10:57:43 +08001142 trace_module_put(module, _RET_IP_);
Christoph Lametere1783a22010-01-05 15:34:50 +09001143 preempt_enable();
Al Virof6a57032006-10-18 01:47:25 -04001144 }
1145}
1146EXPORT_SYMBOL(module_put);
1147
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148#else /* !CONFIG_MODULE_UNLOAD */
Jianjun Kongd1e99d72008-12-08 14:26:29 +08001149static inline void print_unload_info(struct seq_file *m, struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150{
1151 /* We don't know the usage count, or what modules are using. */
Ionut Alexa6da0b562014-11-10 09:31:29 +10301152 seq_puts(m, " - -");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001153}
1154
1155static inline void module_unload_free(struct module *mod)
1156{
1157}
1158
Rusty Russell9bea7f22010-06-05 11:17:37 -06001159int ref_module(struct module *a, struct module *b)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001160{
Rusty Russell9bea7f22010-06-05 11:17:37 -06001161 return strong_try_module_get(b);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001162}
Rusty Russell9bea7f22010-06-05 11:17:37 -06001163EXPORT_SYMBOL_GPL(ref_module);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001164
Rusty Russell9f85a4b2010-08-05 12:59:04 -06001165static inline int module_unload_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166{
Rusty Russell9f85a4b2010-08-05 12:59:04 -06001167 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001168}
1169#endif /* CONFIG_MODULE_UNLOAD */
1170
Kevin Winchester53999bf2012-01-15 19:32:55 -04001171static size_t module_flags_taint(struct module *mod, char *buf)
1172{
1173 size_t l = 0;
Petr Mladek7fd83292016-09-21 13:47:22 +02001174 int i;
Kevin Winchester53999bf2012-01-15 19:32:55 -04001175
Petr Mladek7fd83292016-09-21 13:47:22 +02001176 for (i = 0; i < TAINT_FLAGS_COUNT; i++) {
1177 if (taint_flags[i].module && test_bit(i, &mod->taints))
Larry Finger5eb7c0d2017-01-01 20:25:25 -06001178 buf[l++] = taint_flags[i].c_true;
Petr Mladek7fd83292016-09-21 13:47:22 +02001179 }
1180
Kevin Winchester53999bf2012-01-15 19:32:55 -04001181 return l;
1182}
1183
Kay Sievers1f717402006-11-24 12:15:25 +01001184static ssize_t show_initstate(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301185 struct module_kobject *mk, char *buffer)
Kay Sievers1f717402006-11-24 12:15:25 +01001186{
1187 const char *state = "unknown";
1188
Kay Sievers4befb022011-07-24 22:06:04 +09301189 switch (mk->mod->state) {
Kay Sievers1f717402006-11-24 12:15:25 +01001190 case MODULE_STATE_LIVE:
1191 state = "live";
1192 break;
1193 case MODULE_STATE_COMING:
1194 state = "coming";
1195 break;
1196 case MODULE_STATE_GOING:
1197 state = "going";
1198 break;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10301199 default:
1200 BUG();
Kay Sievers1f717402006-11-24 12:15:25 +01001201 }
1202 return sprintf(buffer, "%s\n", state);
1203}
1204
Kay Sieverscca3e702012-01-13 09:32:15 +10301205static struct module_attribute modinfo_initstate =
1206 __ATTR(initstate, 0444, show_initstate, NULL);
Kay Sievers1f717402006-11-24 12:15:25 +01001207
Kay Sievers88bfa322011-07-24 22:06:04 +09301208static ssize_t store_uevent(struct module_attribute *mattr,
1209 struct module_kobject *mk,
1210 const char *buffer, size_t count)
1211{
Peter Rajnohaf36776f2017-05-09 15:22:30 +02001212 kobject_synth_uevent(&mk->kobj, buffer, count);
Kay Sievers88bfa322011-07-24 22:06:04 +09301213 return count;
1214}
1215
Kay Sieverscca3e702012-01-13 09:32:15 +10301216struct module_attribute module_uevent =
1217 __ATTR(uevent, 0200, NULL, store_uevent);
1218
1219static ssize_t show_coresize(struct module_attribute *mattr,
1220 struct module_kobject *mk, char *buffer)
1221{
Rusty Russell7523e4d2015-11-26 09:44:08 +10301222 return sprintf(buffer, "%u\n", mk->mod->core_layout.size);
Kay Sieverscca3e702012-01-13 09:32:15 +10301223}
1224
1225static struct module_attribute modinfo_coresize =
1226 __ATTR(coresize, 0444, show_coresize, NULL);
1227
1228static ssize_t show_initsize(struct module_attribute *mattr,
1229 struct module_kobject *mk, char *buffer)
1230{
Rusty Russell7523e4d2015-11-26 09:44:08 +10301231 return sprintf(buffer, "%u\n", mk->mod->init_layout.size);
Kay Sieverscca3e702012-01-13 09:32:15 +10301232}
1233
1234static struct module_attribute modinfo_initsize =
1235 __ATTR(initsize, 0444, show_initsize, NULL);
1236
1237static ssize_t show_taint(struct module_attribute *mattr,
1238 struct module_kobject *mk, char *buffer)
1239{
1240 size_t l;
1241
1242 l = module_flags_taint(mk->mod, buffer);
1243 buffer[l++] = '\n';
1244 return l;
1245}
1246
1247static struct module_attribute modinfo_taint =
1248 __ATTR(taint, 0444, show_taint, NULL);
Kay Sievers88bfa322011-07-24 22:06:04 +09301249
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001250static struct module_attribute *modinfo_attrs[] = {
Kay Sieverscca3e702012-01-13 09:32:15 +10301251 &module_uevent,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001252 &modinfo_version,
1253 &modinfo_srcversion,
Kay Sieverscca3e702012-01-13 09:32:15 +10301254 &modinfo_initstate,
1255 &modinfo_coresize,
1256 &modinfo_initsize,
1257 &modinfo_taint,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001258#ifdef CONFIG_MODULE_UNLOAD
Kay Sieverscca3e702012-01-13 09:32:15 +10301259 &modinfo_refcnt,
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001260#endif
1261 NULL,
1262};
1263
Linus Torvalds1da177e2005-04-16 15:20:36 -07001264static const char vermagic[] = VERMAGIC_STRING;
1265
Rusty Russellc6e665c2009-03-31 13:05:33 -06001266static int try_to_force_load(struct module *mod, const char *reason)
Linus Torvalds826e4502008-05-04 17:04:16 -07001267{
1268#ifdef CONFIG_MODULE_FORCE_LOAD
Andi Kleen25ddbb12008-10-15 22:01:41 -07001269 if (!test_taint(TAINT_FORCED_MODULE))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001270 pr_warn("%s: %s: kernel tainted.\n", mod->name, reason);
Rusty Russell373d4d02013-01-21 17:17:39 +10301271 add_taint_module(mod, TAINT_FORCED_MODULE, LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds826e4502008-05-04 17:04:16 -07001272 return 0;
1273#else
1274 return -ENOEXEC;
1275#endif
1276}
1277
Linus Torvalds1da177e2005-04-16 15:20:36 -07001278#ifdef CONFIG_MODVERSIONS
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001279
1280static u32 resolve_rel_crc(const s32 *crc)
Rusty Russelld4703ae2009-12-15 16:28:32 -06001281{
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001282 return *(u32 *)((void *)crc + *crc);
Rusty Russelld4703ae2009-12-15 16:28:32 -06001283}
1284
Kees Cook49019422017-04-21 15:35:26 -07001285static int check_version(const struct load_info *info,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286 const char *symname,
Ionut Alexa6da0b562014-11-10 09:31:29 +10301287 struct module *mod,
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001288 const s32 *crc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001289{
Kees Cook49019422017-04-21 15:35:26 -07001290 Elf_Shdr *sechdrs = info->sechdrs;
1291 unsigned int versindex = info->index.vers;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292 unsigned int i, num_versions;
1293 struct modversion_info *versions;
1294
1295 /* Exporting module didn't supply crcs? OK, we're already tainted. */
1296 if (!crc)
1297 return 1;
1298
Rusty Russella5dd6972008-05-09 16:24:21 +10001299 /* No versions at all? modprobe --force does this. */
1300 if (versindex == 0)
1301 return try_to_force_load(mod, symname) == 0;
1302
Linus Torvalds1da177e2005-04-16 15:20:36 -07001303 versions = (void *) sechdrs[versindex].sh_addr;
1304 num_versions = sechdrs[versindex].sh_size
1305 / sizeof(struct modversion_info);
1306
1307 for (i = 0; i < num_versions; i++) {
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001308 u32 crcval;
1309
Linus Torvalds1da177e2005-04-16 15:20:36 -07001310 if (strcmp(versions[i].name, symname) != 0)
1311 continue;
1312
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001313 if (IS_ENABLED(CONFIG_MODULE_REL_CRCS))
1314 crcval = resolve_rel_crc(crc);
1315 else
1316 crcval = *crc;
1317 if (versions[i].crc == crcval)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318 return 1;
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001319 pr_debug("Found checksum %X vs module %lX\n",
1320 crcval, versions[i].crc);
Linus Torvalds826e4502008-05-04 17:04:16 -07001321 goto bad_version;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 }
Linus Torvalds826e4502008-05-04 17:04:16 -07001323
Linus Torvaldsfaaae2a2016-11-29 15:20:14 -08001324 /* Broken toolchain. Warn once, then let it go.. */
Kees Cook3e2e8572017-04-21 15:35:27 -07001325 pr_warn_once("%s: no symbol version for %s\n", info->name, symname);
Linus Torvaldsfaaae2a2016-11-29 15:20:14 -08001326 return 1;
Linus Torvalds826e4502008-05-04 17:04:16 -07001327
1328bad_version:
Ionut Alexa6da0b562014-11-10 09:31:29 +10301329 pr_warn("%s: disagrees about version of symbol %s\n",
Kees Cook3e2e8572017-04-21 15:35:27 -07001330 info->name, symname);
Linus Torvalds826e4502008-05-04 17:04:16 -07001331 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332}
1333
Kees Cook49019422017-04-21 15:35:26 -07001334static inline int check_modstruct_version(const struct load_info *info,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001335 struct module *mod)
1336{
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001337 const s32 *crc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001338
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301339 /*
1340 * Since this should be found in kernel (which can't be removed), no
1341 * locking is necessary -- use preempt_disable() to placate lockdep.
1342 */
1343 preempt_disable();
Masahiro Yamada996302c2018-06-24 00:37:44 +09001344 if (!find_symbol("module_layout", NULL, &crc, true, false)) {
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301345 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001346 BUG();
Peter Zijlstra926a59b2015-05-27 11:09:35 +09301347 }
1348 preempt_enable();
Masahiro Yamada996302c2018-06-24 00:37:44 +09001349 return check_version(info, "module_layout", mod, crc);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350}
1351
Rusty Russell91e37a72008-05-09 16:25:28 +10001352/* First part is kernel version, which we ignore if module has crcs. */
1353static inline int same_magic(const char *amagic, const char *bmagic,
1354 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001355{
Rusty Russell91e37a72008-05-09 16:25:28 +10001356 if (has_crcs) {
1357 amagic += strcspn(amagic, " ");
1358 bmagic += strcspn(bmagic, " ");
1359 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 return strcmp(amagic, bmagic) == 0;
1361}
1362#else
Kees Cook49019422017-04-21 15:35:26 -07001363static inline int check_version(const struct load_info *info,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001364 const char *symname,
Ionut Alexa6da0b562014-11-10 09:31:29 +10301365 struct module *mod,
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001366 const s32 *crc)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001367{
1368 return 1;
1369}
1370
Kees Cook49019422017-04-21 15:35:26 -07001371static inline int check_modstruct_version(const struct load_info *info,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372 struct module *mod)
1373{
1374 return 1;
1375}
1376
Rusty Russell91e37a72008-05-09 16:25:28 +10001377static inline int same_magic(const char *amagic, const char *bmagic,
1378 bool has_crcs)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001379{
1380 return strcmp(amagic, bmagic) == 0;
1381}
1382#endif /* CONFIG_MODVERSIONS */
1383
Rusty Russell75676502010-06-05 11:17:36 -06001384/* Resolve a symbol for this module. I.e. if we find one, record usage. */
Rusty Russell49668682010-08-05 12:59:10 -06001385static const struct kernel_symbol *resolve_symbol(struct module *mod,
1386 const struct load_info *info,
Tim Abbott414fd312008-12-05 19:03:56 -05001387 const char *name,
Rusty Russell9bea7f22010-06-05 11:17:37 -06001388 char ownername[])
Linus Torvalds1da177e2005-04-16 15:20:36 -07001389{
1390 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05001391 const struct kernel_symbol *sym;
Ard Biesheuvel71810db2017-02-03 09:54:06 +00001392 const s32 *crc;
Rusty Russell9bea7f22010-06-05 11:17:37 -06001393 int err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394
Peter Zijlstrad64810f2015-02-11 15:01:13 +10301395 /*
1396 * The module_mutex should not be a heavily contended lock;
1397 * if we get the occasional sleep here, we'll go an extra iteration
1398 * in the wait_event_interruptible(), which is harmless.
1399 */
1400 sched_annotate_sleep();
Rusty Russell75676502010-06-05 11:17:36 -06001401 mutex_lock(&module_mutex);
Tim Abbott414fd312008-12-05 19:03:56 -05001402 sym = find_symbol(name, &owner, &crc,
Andi Kleen25ddbb12008-10-15 22:01:41 -07001403 !(mod->taints & (1 << TAINT_PROPRIETARY_MODULE)), true);
Rusty Russell9bea7f22010-06-05 11:17:37 -06001404 if (!sym)
1405 goto unlock;
1406
Kees Cook49019422017-04-21 15:35:26 -07001407 if (!check_version(info, name, mod, crc)) {
Rusty Russell9bea7f22010-06-05 11:17:37 -06001408 sym = ERR_PTR(-EINVAL);
1409 goto getname;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 }
Rusty Russell9bea7f22010-06-05 11:17:37 -06001411
1412 err = ref_module(mod, owner);
1413 if (err) {
1414 sym = ERR_PTR(err);
1415 goto getname;
1416 }
1417
1418getname:
1419 /* We must make copy under the lock if we failed to get ref. */
1420 strncpy(ownername, module_name(owner), MODULE_NAME_LEN);
1421unlock:
Rusty Russell75676502010-06-05 11:17:36 -06001422 mutex_unlock(&module_mutex);
Linus Torvalds218ce732010-05-25 16:48:30 -07001423 return sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424}
1425
Rusty Russell49668682010-08-05 12:59:10 -06001426static const struct kernel_symbol *
1427resolve_symbol_wait(struct module *mod,
1428 const struct load_info *info,
1429 const char *name)
Rusty Russell9bea7f22010-06-05 11:17:37 -06001430{
1431 const struct kernel_symbol *ksym;
Rusty Russell49668682010-08-05 12:59:10 -06001432 char owner[MODULE_NAME_LEN];
Rusty Russell9bea7f22010-06-05 11:17:37 -06001433
1434 if (wait_event_interruptible_timeout(module_wq,
Rusty Russell49668682010-08-05 12:59:10 -06001435 !IS_ERR(ksym = resolve_symbol(mod, info, name, owner))
1436 || PTR_ERR(ksym) != -EBUSY,
Rusty Russell9bea7f22010-06-05 11:17:37 -06001437 30 * HZ) <= 0) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001438 pr_warn("%s: gave up waiting for init of module %s.\n",
1439 mod->name, owner);
Rusty Russell9bea7f22010-06-05 11:17:37 -06001440 }
1441 return ksym;
1442}
1443
Linus Torvalds1da177e2005-04-16 15:20:36 -07001444/*
1445 * /sys/module/foo/sections stuff
1446 * J. Corbet <corbet@lwn.net>
1447 */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001448#ifdef CONFIG_SYSFS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001449
Rusty Russell8f6d0372010-08-05 12:59:09 -06001450#ifdef CONFIG_KALLSYMS
Ben Hutchings10b465a2009-12-19 14:43:01 +00001451static inline bool sect_empty(const Elf_Shdr *sect)
1452{
1453 return !(sect->sh_flags & SHF_ALLOC) || sect->sh_size == 0;
1454}
1455
Ionut Alexa6da0b562014-11-10 09:31:29 +10301456struct module_sect_attr {
Rusty Russella58730c2008-03-13 09:03:44 +00001457 struct module_attribute mattr;
1458 char *name;
1459 unsigned long address;
1460};
1461
Ionut Alexa6da0b562014-11-10 09:31:29 +10301462struct module_sect_attrs {
Rusty Russella58730c2008-03-13 09:03:44 +00001463 struct attribute_group grp;
1464 unsigned int nsections;
1465 struct module_sect_attr attrs[0];
1466};
1467
Linus Torvalds1da177e2005-04-16 15:20:36 -07001468static ssize_t module_sect_show(struct module_attribute *mattr,
Kay Sievers4befb022011-07-24 22:06:04 +09301469 struct module_kobject *mk, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001470{
1471 struct module_sect_attr *sattr =
1472 container_of(mattr, struct module_sect_attr, mattr);
Thomas Richterbe71eda2018-04-18 09:14:36 +02001473 return sprintf(buf, "0x%px\n", kptr_restrict < 2 ?
1474 (void *)sattr->address : NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001475}
1476
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001477static void free_sect_attrs(struct module_sect_attrs *sect_attrs)
1478{
Rusty Russella58730c2008-03-13 09:03:44 +00001479 unsigned int section;
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001480
1481 for (section = 0; section < sect_attrs->nsections; section++)
1482 kfree(sect_attrs->attrs[section].name);
1483 kfree(sect_attrs);
1484}
1485
Rusty Russell8f6d0372010-08-05 12:59:09 -06001486static void add_sect_attrs(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001487{
1488 unsigned int nloaded = 0, i, size[2];
1489 struct module_sect_attrs *sect_attrs;
1490 struct module_sect_attr *sattr;
1491 struct attribute **gattr;
Daniel Walker22a8bde2007-10-18 03:06:07 -07001492
Linus Torvalds1da177e2005-04-16 15:20:36 -07001493 /* Count loaded sections and allocate structures */
Rusty Russell8f6d0372010-08-05 12:59:09 -06001494 for (i = 0; i < info->hdr->e_shnum; i++)
1495 if (!sect_empty(&info->sechdrs[i]))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001496 nloaded++;
1497 size[0] = ALIGN(sizeof(*sect_attrs)
1498 + nloaded * sizeof(sect_attrs->attrs[0]),
1499 sizeof(sect_attrs->grp.attrs[0]));
1500 size[1] = (nloaded + 1) * sizeof(sect_attrs->grp.attrs[0]);
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001501 sect_attrs = kzalloc(size[0] + size[1], GFP_KERNEL);
1502 if (sect_attrs == NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001503 return;
1504
1505 /* Setup section attributes. */
1506 sect_attrs->grp.name = "sections";
1507 sect_attrs->grp.attrs = (void *)sect_attrs + size[0];
1508
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001509 sect_attrs->nsections = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001510 sattr = &sect_attrs->attrs[0];
1511 gattr = &sect_attrs->grp.attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001512 for (i = 0; i < info->hdr->e_shnum; i++) {
1513 Elf_Shdr *sec = &info->sechdrs[i];
1514 if (sect_empty(sec))
Helge Deller35dead42009-12-03 00:29:15 +01001515 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001516 sattr->address = sec->sh_addr;
1517 sattr->name = kstrdup(info->secstrings + sec->sh_name,
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001518 GFP_KERNEL);
1519 if (sattr->name == NULL)
1520 goto out;
1521 sect_attrs->nsections++;
Eric W. Biederman361795b2010-02-12 13:41:56 -08001522 sysfs_attr_init(&sattr->mattr.attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001523 sattr->mattr.show = module_sect_show;
1524 sattr->mattr.store = NULL;
1525 sattr->mattr.attr.name = sattr->name;
Linus Torvalds277642d2017-11-12 17:00:53 -08001526 sattr->mattr.attr.mode = S_IRUSR;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527 *(gattr++) = &(sattr++)->mattr.attr;
1528 }
1529 *gattr = NULL;
1530
1531 if (sysfs_create_group(&mod->mkobj.kobj, &sect_attrs->grp))
1532 goto out;
1533
1534 mod->sect_attrs = sect_attrs;
1535 return;
1536 out:
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001537 free_sect_attrs(sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001538}
1539
1540static void remove_sect_attrs(struct module *mod)
1541{
1542 if (mod->sect_attrs) {
1543 sysfs_remove_group(&mod->mkobj.kobj,
1544 &mod->sect_attrs->grp);
1545 /* We are positive that no one is using any sect attrs
1546 * at this point. Deallocate immediately. */
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001547 free_sect_attrs(mod->sect_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001548 mod->sect_attrs = NULL;
1549 }
1550}
1551
Roland McGrath6d760132007-10-16 23:26:40 -07001552/*
1553 * /sys/module/foo/notes/.section.name gives contents of SHT_NOTE sections.
1554 */
1555
1556struct module_notes_attrs {
1557 struct kobject *dir;
1558 unsigned int notes;
1559 struct bin_attribute attrs[0];
1560};
1561
Chris Wright2c3c8be2010-05-12 18:28:57 -07001562static ssize_t module_notes_read(struct file *filp, struct kobject *kobj,
Roland McGrath6d760132007-10-16 23:26:40 -07001563 struct bin_attribute *bin_attr,
1564 char *buf, loff_t pos, size_t count)
1565{
1566 /*
1567 * The caller checked the pos and count against our size.
1568 */
1569 memcpy(buf, bin_attr->private + pos, count);
1570 return count;
1571}
1572
1573static void free_notes_attrs(struct module_notes_attrs *notes_attrs,
1574 unsigned int i)
1575{
1576 if (notes_attrs->dir) {
1577 while (i-- > 0)
1578 sysfs_remove_bin_file(notes_attrs->dir,
1579 &notes_attrs->attrs[i]);
Alexey Dobriyane9432092008-09-23 23:51:11 +04001580 kobject_put(notes_attrs->dir);
Roland McGrath6d760132007-10-16 23:26:40 -07001581 }
1582 kfree(notes_attrs);
1583}
1584
Rusty Russell8f6d0372010-08-05 12:59:09 -06001585static void add_notes_attrs(struct module *mod, const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001586{
1587 unsigned int notes, loaded, i;
1588 struct module_notes_attrs *notes_attrs;
1589 struct bin_attribute *nattr;
1590
Ingo Molnarea6bff32009-08-28 10:44:56 +02001591 /* failed to create section attributes, so can't create notes */
1592 if (!mod->sect_attrs)
1593 return;
1594
Roland McGrath6d760132007-10-16 23:26:40 -07001595 /* Count notes sections and allocate structures. */
1596 notes = 0;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001597 for (i = 0; i < info->hdr->e_shnum; i++)
1598 if (!sect_empty(&info->sechdrs[i]) &&
1599 (info->sechdrs[i].sh_type == SHT_NOTE))
Roland McGrath6d760132007-10-16 23:26:40 -07001600 ++notes;
1601
1602 if (notes == 0)
1603 return;
1604
Kees Cookacafe7e2018-05-08 13:45:50 -07001605 notes_attrs = kzalloc(struct_size(notes_attrs, attrs, notes),
Roland McGrath6d760132007-10-16 23:26:40 -07001606 GFP_KERNEL);
1607 if (notes_attrs == NULL)
1608 return;
1609
1610 notes_attrs->notes = notes;
1611 nattr = &notes_attrs->attrs[0];
Rusty Russell8f6d0372010-08-05 12:59:09 -06001612 for (loaded = i = 0; i < info->hdr->e_shnum; ++i) {
1613 if (sect_empty(&info->sechdrs[i]))
Roland McGrath6d760132007-10-16 23:26:40 -07001614 continue;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001615 if (info->sechdrs[i].sh_type == SHT_NOTE) {
Eric W. Biederman361795b2010-02-12 13:41:56 -08001616 sysfs_bin_attr_init(nattr);
Roland McGrath6d760132007-10-16 23:26:40 -07001617 nattr->attr.name = mod->sect_attrs->attrs[loaded].name;
1618 nattr->attr.mode = S_IRUGO;
Rusty Russell8f6d0372010-08-05 12:59:09 -06001619 nattr->size = info->sechdrs[i].sh_size;
1620 nattr->private = (void *) info->sechdrs[i].sh_addr;
Roland McGrath6d760132007-10-16 23:26:40 -07001621 nattr->read = module_notes_read;
1622 ++nattr;
1623 }
1624 ++loaded;
1625 }
1626
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001627 notes_attrs->dir = kobject_create_and_add("notes", &mod->mkobj.kobj);
Roland McGrath6d760132007-10-16 23:26:40 -07001628 if (!notes_attrs->dir)
1629 goto out;
1630
1631 for (i = 0; i < notes; ++i)
1632 if (sysfs_create_bin_file(notes_attrs->dir,
1633 &notes_attrs->attrs[i]))
1634 goto out;
1635
1636 mod->notes_attrs = notes_attrs;
1637 return;
1638
1639 out:
1640 free_notes_attrs(notes_attrs, i);
1641}
1642
1643static void remove_notes_attrs(struct module *mod)
1644{
1645 if (mod->notes_attrs)
1646 free_notes_attrs(mod->notes_attrs, mod->notes_attrs->notes);
1647}
1648
Linus Torvalds1da177e2005-04-16 15:20:36 -07001649#else
Ian S. Nelson04b1db92006-09-29 02:01:31 -07001650
Rusty Russell8f6d0372010-08-05 12:59:09 -06001651static inline void add_sect_attrs(struct module *mod,
1652 const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001653{
1654}
1655
1656static inline void remove_sect_attrs(struct module *mod)
1657{
1658}
Roland McGrath6d760132007-10-16 23:26:40 -07001659
Rusty Russell8f6d0372010-08-05 12:59:09 -06001660static inline void add_notes_attrs(struct module *mod,
1661 const struct load_info *info)
Roland McGrath6d760132007-10-16 23:26:40 -07001662{
1663}
1664
1665static inline void remove_notes_attrs(struct module *mod)
1666{
1667}
Rusty Russell8f6d0372010-08-05 12:59:09 -06001668#endif /* CONFIG_KALLSYMS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001670static void del_usage_links(struct module *mod)
1671{
1672#ifdef CONFIG_MODULE_UNLOAD
1673 struct module_use *use;
1674
Rusty Russell75676502010-06-05 11:17:36 -06001675 mutex_lock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001676 list_for_each_entry(use, &mod->target_list, target_list)
1677 sysfs_remove_link(use->target->holders_dir, mod->name);
Rusty Russell75676502010-06-05 11:17:36 -06001678 mutex_unlock(&module_mutex);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001679#endif
1680}
1681
Corentin Labbe1ba5c082017-06-06 14:17:39 +02001682static int add_usage_links(struct module *mod)
1683{
1684 int ret = 0;
1685#ifdef CONFIG_MODULE_UNLOAD
1686 struct module_use *use;
1687
1688 mutex_lock(&module_mutex);
1689 list_for_each_entry(use, &mod->target_list, target_list) {
1690 ret = sysfs_create_link(use->target->holders_dir,
1691 &mod->mkobj.kobj, mod->name);
1692 if (ret)
1693 break;
1694 }
1695 mutex_unlock(&module_mutex);
1696 if (ret)
1697 del_usage_links(mod);
1698#endif
1699 return ret;
1700}
1701
Rusty Russell6407ebb22010-06-05 11:17:36 -06001702static int module_add_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001703{
1704 struct module_attribute *attr;
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001705 struct module_attribute *temp_attr;
Matt Domschc988d2b2005-06-23 22:05:15 -07001706 int error = 0;
1707 int i;
1708
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001709 mod->modinfo_attrs = kzalloc((sizeof(struct module_attribute) *
1710 (ARRAY_SIZE(modinfo_attrs) + 1)),
1711 GFP_KERNEL);
1712 if (!mod->modinfo_attrs)
1713 return -ENOMEM;
1714
1715 temp_attr = mod->modinfo_attrs;
Matt Domschc988d2b2005-06-23 22:05:15 -07001716 for (i = 0; (attr = modinfo_attrs[i]) && !error; i++) {
Rusty Russellc75b5902016-04-12 05:03:09 +09301717 if (!attr->test || attr->test(mod)) {
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001718 memcpy(temp_attr, attr, sizeof(*temp_attr));
Eric W. Biederman361795b2010-02-12 13:41:56 -08001719 sysfs_attr_init(&temp_attr->attr);
Ionut Alexa6da0b562014-11-10 09:31:29 +10301720 error = sysfs_create_file(&mod->mkobj.kobj,
1721 &temp_attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001722 ++temp_attr;
1723 }
Matt Domschc988d2b2005-06-23 22:05:15 -07001724 }
1725 return error;
1726}
1727
Rusty Russell6407ebb22010-06-05 11:17:36 -06001728static void module_remove_modinfo_attrs(struct module *mod)
Matt Domschc988d2b2005-06-23 22:05:15 -07001729{
1730 struct module_attribute *attr;
1731 int i;
1732
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001733 for (i = 0; (attr = &mod->modinfo_attrs[i]); i++) {
1734 /* pick a field to test for end of list */
1735 if (!attr->attr.name)
1736 break;
Ionut Alexa6da0b562014-11-10 09:31:29 +10301737 sysfs_remove_file(&mod->mkobj.kobj, &attr->attr);
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001738 if (attr->free)
1739 attr->free(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001740 }
Greg Kroah-Hartman03e88ae12006-02-16 13:50:23 -08001741 kfree(mod->modinfo_attrs);
Matt Domschc988d2b2005-06-23 22:05:15 -07001742}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001743
Li Zhong942e4432013-09-03 16:33:57 +09301744static void mod_kobject_put(struct module *mod)
1745{
1746 DECLARE_COMPLETION_ONSTACK(c);
1747 mod->mkobj.kobj_completion = &c;
1748 kobject_put(&mod->mkobj.kobj);
1749 wait_for_completion(&c);
1750}
1751
Rusty Russell6407ebb22010-06-05 11:17:36 -06001752static int mod_sysfs_init(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001753{
1754 int err;
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001755 struct kobject *kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001756
Greg Kroah-Hartman823bccf2007-04-13 13:15:19 -07001757 if (!module_sysfs_initialized) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001758 pr_err("%s: module sysfs not initialized\n", mod->name);
Ed Swierk1cc5f712006-09-25 16:25:36 -07001759 err = -EINVAL;
1760 goto out;
1761 }
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001762
1763 kobj = kset_find_obj(module_kset, mod->name);
1764 if (kobj) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08001765 pr_err("%s: module is already loaded\n", mod->name);
Greg Kroah-Hartman6494a932008-01-27 15:38:40 -08001766 kobject_put(kobj);
1767 err = -EINVAL;
1768 goto out;
1769 }
1770
Linus Torvalds1da177e2005-04-16 15:20:36 -07001771 mod->mkobj.mod = mod;
Kay Sieverse17e0f52006-11-24 12:15:25 +01001772
Greg Kroah-Hartmanac3c8142007-12-17 23:05:35 -07001773 memset(&mod->mkobj.kobj, 0, sizeof(mod->mkobj.kobj));
1774 mod->mkobj.kobj.kset = module_kset;
1775 err = kobject_init_and_add(&mod->mkobj.kobj, &module_ktype, NULL,
1776 "%s", mod->name);
1777 if (err)
Li Zhong942e4432013-09-03 16:33:57 +09301778 mod_kobject_put(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001779
Kay Sievers97c146ef2007-11-29 23:46:11 +01001780 /* delay uevent until full sysfs population */
Kay Sievers270a6c42007-01-18 13:26:15 +01001781out:
1782 return err;
1783}
1784
Rusty Russell6407ebb22010-06-05 11:17:36 -06001785static int mod_sysfs_setup(struct module *mod,
Rusty Russell8f6d0372010-08-05 12:59:09 -06001786 const struct load_info *info,
Kay Sievers270a6c42007-01-18 13:26:15 +01001787 struct kernel_param *kparam,
1788 unsigned int num_params)
1789{
1790 int err;
1791
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001792 err = mod_sysfs_init(mod);
1793 if (err)
1794 goto out;
1795
Greg Kroah-Hartman4ff6abf2007-11-05 22:24:43 -08001796 mod->holders_dir = kobject_create_and_add("holders", &mod->mkobj.kobj);
Akinobu Mita240936e2007-04-26 00:12:09 -07001797 if (!mod->holders_dir) {
1798 err = -ENOMEM;
Kay Sievers270a6c42007-01-18 13:26:15 +01001799 goto out_unreg;
Akinobu Mita240936e2007-04-26 00:12:09 -07001800 }
Kay Sievers270a6c42007-01-18 13:26:15 +01001801
Linus Torvalds1da177e2005-04-16 15:20:36 -07001802 err = module_param_sysfs_setup(mod, kparam, num_params);
1803 if (err)
Kay Sievers270a6c42007-01-18 13:26:15 +01001804 goto out_unreg_holders;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001805
Matt Domschc988d2b2005-06-23 22:05:15 -07001806 err = module_add_modinfo_attrs(mod);
1807 if (err)
Kay Sieverse17e0f52006-11-24 12:15:25 +01001808 goto out_unreg_param;
Matt Domschc988d2b2005-06-23 22:05:15 -07001809
Corentin Labbe1ba5c082017-06-06 14:17:39 +02001810 err = add_usage_links(mod);
1811 if (err)
1812 goto out_unreg_modinfo_attrs;
1813
Rusty Russell8f6d0372010-08-05 12:59:09 -06001814 add_sect_attrs(mod, info);
1815 add_notes_attrs(mod, info);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001816
Kay Sieverse17e0f52006-11-24 12:15:25 +01001817 kobject_uevent(&mod->mkobj.kobj, KOBJ_ADD);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001818 return 0;
1819
Corentin Labbe1ba5c082017-06-06 14:17:39 +02001820out_unreg_modinfo_attrs:
1821 module_remove_modinfo_attrs(mod);
Kay Sieverse17e0f52006-11-24 12:15:25 +01001822out_unreg_param:
1823 module_param_sysfs_remove(mod);
Kay Sievers270a6c42007-01-18 13:26:15 +01001824out_unreg_holders:
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001825 kobject_put(mod->holders_dir);
Kay Sievers270a6c42007-01-18 13:26:15 +01001826out_unreg:
Li Zhong942e4432013-09-03 16:33:57 +09301827 mod_kobject_put(mod);
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001828out:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001829 return err;
1830}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001831
1832static void mod_sysfs_fini(struct module *mod)
1833{
Rusty Russell8f6d0372010-08-05 12:59:09 -06001834 remove_notes_attrs(mod);
1835 remove_sect_attrs(mod);
Li Zhong942e4432013-09-03 16:33:57 +09301836 mod_kobject_put(mod);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001837}
1838
Rusty Russellcf2fde72015-06-26 06:44:38 +09301839static void init_param_lock(struct module *mod)
1840{
1841 mutex_init(&mod->param_lock);
1842}
Rusty Russell8f6d0372010-08-05 12:59:09 -06001843#else /* !CONFIG_SYSFS */
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001844
Rusty Russell8f6d0372010-08-05 12:59:09 -06001845static int mod_sysfs_setup(struct module *mod,
1846 const struct load_info *info,
Rusty Russell6407ebb22010-06-05 11:17:36 -06001847 struct kernel_param *kparam,
1848 unsigned int num_params)
1849{
1850 return 0;
1851}
1852
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001853static void mod_sysfs_fini(struct module *mod)
1854{
1855}
1856
Rusty Russell36b03602010-08-05 12:59:09 -06001857static void module_remove_modinfo_attrs(struct module *mod)
1858{
1859}
1860
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001861static void del_usage_links(struct module *mod)
1862{
1863}
1864
Rusty Russellcf2fde72015-06-26 06:44:38 +09301865static void init_param_lock(struct module *mod)
1866{
1867}
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001868#endif /* CONFIG_SYSFS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001869
Rusty Russell36b03602010-08-05 12:59:09 -06001870static void mod_sysfs_teardown(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871{
Rusty Russell80a3d1b2010-06-05 11:17:36 -06001872 del_usage_links(mod);
Matt Domschc988d2b2005-06-23 22:05:15 -07001873 module_remove_modinfo_attrs(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001874 module_param_sysfs_remove(mod);
Greg Kroah-Hartman78a2d902007-12-20 08:13:05 -08001875 kobject_put(mod->mkobj.drivers_dir);
1876 kobject_put(mod->holders_dir);
Denis V. Lunev34e4e2f2008-05-20 13:59:48 +04001877 mod_sysfs_fini(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001878}
1879
Laura Abbott0f5bf6d2017-02-06 16:31:58 -08001880#ifdef CONFIG_STRICT_MODULE_RWX
matthieu castet84e1c6b2010-11-16 22:35:16 +01001881/*
1882 * LKM RO/NX protection: protect module's text/ro-data
1883 * from modification and any data from execution.
Rusty Russell85c898d2015-11-26 09:45:08 +10301884 *
1885 * General layout of module is:
Jessica Yu444d13f2016-07-27 12:06:21 +09301886 * [text] [read-only-data] [ro-after-init] [writable data]
1887 * text_size -----^ ^ ^ ^
1888 * ro_size ------------------------| | |
1889 * ro_after_init_size -----------------------------| |
1890 * size -----------------------------------------------------------|
Rusty Russell85c898d2015-11-26 09:45:08 +10301891 *
1892 * These values are always page-aligned (as is base)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001893 */
Rusty Russell85c898d2015-11-26 09:45:08 +10301894static void frob_text(const struct module_layout *layout,
1895 int (*set_memory)(unsigned long start, int num_pages))
matthieu castet84e1c6b2010-11-16 22:35:16 +01001896{
Rusty Russell85c898d2015-11-26 09:45:08 +10301897 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1898 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1899 set_memory((unsigned long)layout->base,
1900 layout->text_size >> PAGE_SHIFT);
matthieu castet84e1c6b2010-11-16 22:35:16 +01001901}
1902
Rusty Russell85c898d2015-11-26 09:45:08 +10301903static void frob_rodata(const struct module_layout *layout,
1904 int (*set_memory)(unsigned long start, int num_pages))
matthieu castet84e1c6b2010-11-16 22:35:16 +01001905{
Rusty Russell85c898d2015-11-26 09:45:08 +10301906 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1907 BUG_ON((unsigned long)layout->text_size & (PAGE_SIZE-1));
1908 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1909 set_memory((unsigned long)layout->base + layout->text_size,
1910 (layout->ro_size - layout->text_size) >> PAGE_SHIFT);
matthieu castet84e1c6b2010-11-16 22:35:16 +01001911}
1912
Jessica Yu444d13f2016-07-27 12:06:21 +09301913static void frob_ro_after_init(const struct module_layout *layout,
1914 int (*set_memory)(unsigned long start, int num_pages))
1915{
1916 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
1917 BUG_ON((unsigned long)layout->ro_size & (PAGE_SIZE-1));
1918 BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
1919 set_memory((unsigned long)layout->base + layout->ro_size,
1920 (layout->ro_after_init_size - layout->ro_size) >> PAGE_SHIFT);
1921}
1922
Rusty Russell85c898d2015-11-26 09:45:08 +10301923static void frob_writable_data(const struct module_layout *layout,
1924 int (*set_memory)(unsigned long start, int num_pages))
matthieu castet84e1c6b2010-11-16 22:35:16 +01001925{
Rusty Russell85c898d2015-11-26 09:45:08 +10301926 BUG_ON((unsigned long)layout->base & (PAGE_SIZE-1));
Jessica Yu444d13f2016-07-27 12:06:21 +09301927 BUG_ON((unsigned long)layout->ro_after_init_size & (PAGE_SIZE-1));
Rusty Russell85c898d2015-11-26 09:45:08 +10301928 BUG_ON((unsigned long)layout->size & (PAGE_SIZE-1));
Jessica Yu444d13f2016-07-27 12:06:21 +09301929 set_memory((unsigned long)layout->base + layout->ro_after_init_size,
1930 (layout->size - layout->ro_after_init_size) >> PAGE_SHIFT);
Jan Glauber01526ed2011-05-19 16:55:26 -06001931}
1932
Rusty Russell85c898d2015-11-26 09:45:08 +10301933/* livepatching wants to disable read-only so it can frob module. */
1934void module_disable_ro(const struct module *mod)
Jan Glauber01526ed2011-05-19 16:55:26 -06001935{
AKASHI Takahiro39290b32016-11-14 15:15:05 +09001936 if (!rodata_enabled)
1937 return;
1938
Rusty Russell85c898d2015-11-26 09:45:08 +10301939 frob_text(&mod->core_layout, set_memory_rw);
1940 frob_rodata(&mod->core_layout, set_memory_rw);
Jessica Yu444d13f2016-07-27 12:06:21 +09301941 frob_ro_after_init(&mod->core_layout, set_memory_rw);
Rusty Russell85c898d2015-11-26 09:45:08 +10301942 frob_text(&mod->init_layout, set_memory_rw);
1943 frob_rodata(&mod->init_layout, set_memory_rw);
Josh Poimboeuf20ef10c2015-11-26 09:42:08 +10301944}
1945
Jessica Yu444d13f2016-07-27 12:06:21 +09301946void module_enable_ro(const struct module *mod, bool after_init)
Josh Poimboeuf20ef10c2015-11-26 09:42:08 +10301947{
AKASHI Takahiro39290b32016-11-14 15:15:05 +09001948 if (!rodata_enabled)
1949 return;
1950
Rusty Russell85c898d2015-11-26 09:45:08 +10301951 frob_text(&mod->core_layout, set_memory_ro);
1952 frob_rodata(&mod->core_layout, set_memory_ro);
1953 frob_text(&mod->init_layout, set_memory_ro);
1954 frob_rodata(&mod->init_layout, set_memory_ro);
Jessica Yu444d13f2016-07-27 12:06:21 +09301955
1956 if (after_init)
1957 frob_ro_after_init(&mod->core_layout, set_memory_ro);
Jan Glauber01526ed2011-05-19 16:55:26 -06001958}
1959
Rusty Russell85c898d2015-11-26 09:45:08 +10301960static void module_enable_nx(const struct module *mod)
Jan Glauber01526ed2011-05-19 16:55:26 -06001961{
Rusty Russell85c898d2015-11-26 09:45:08 +10301962 frob_rodata(&mod->core_layout, set_memory_nx);
Jessica Yu444d13f2016-07-27 12:06:21 +09301963 frob_ro_after_init(&mod->core_layout, set_memory_nx);
Rusty Russell85c898d2015-11-26 09:45:08 +10301964 frob_writable_data(&mod->core_layout, set_memory_nx);
1965 frob_rodata(&mod->init_layout, set_memory_nx);
1966 frob_writable_data(&mod->init_layout, set_memory_nx);
1967}
1968
1969static void module_disable_nx(const struct module *mod)
1970{
1971 frob_rodata(&mod->core_layout, set_memory_x);
Jessica Yu444d13f2016-07-27 12:06:21 +09301972 frob_ro_after_init(&mod->core_layout, set_memory_x);
Rusty Russell85c898d2015-11-26 09:45:08 +10301973 frob_writable_data(&mod->core_layout, set_memory_x);
1974 frob_rodata(&mod->init_layout, set_memory_x);
1975 frob_writable_data(&mod->init_layout, set_memory_x);
matthieu castet84e1c6b2010-11-16 22:35:16 +01001976}
1977
1978/* Iterate through all modules and set each module's text as RW */
Daniel J Blueman5d05c702011-03-08 22:01:47 +08001979void set_all_modules_text_rw(void)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001980{
1981 struct module *mod;
1982
AKASHI Takahiro39290b32016-11-14 15:15:05 +09001983 if (!rodata_enabled)
1984 return;
1985
matthieu castet84e1c6b2010-11-16 22:35:16 +01001986 mutex_lock(&module_mutex);
1987 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10301988 if (mod->state == MODULE_STATE_UNFORMED)
1989 continue;
Rusty Russell85c898d2015-11-26 09:45:08 +10301990
1991 frob_text(&mod->core_layout, set_memory_rw);
1992 frob_text(&mod->init_layout, set_memory_rw);
matthieu castet84e1c6b2010-11-16 22:35:16 +01001993 }
1994 mutex_unlock(&module_mutex);
1995}
1996
1997/* Iterate through all modules and set each module's text as RO */
Daniel J Blueman5d05c702011-03-08 22:01:47 +08001998void set_all_modules_text_ro(void)
matthieu castet84e1c6b2010-11-16 22:35:16 +01001999{
2000 struct module *mod;
2001
AKASHI Takahiro39290b32016-11-14 15:15:05 +09002002 if (!rodata_enabled)
2003 return;
2004
matthieu castet84e1c6b2010-11-16 22:35:16 +01002005 mutex_lock(&module_mutex);
2006 list_for_each_entry_rcu(mod, &modules, list) {
Aaron Tomlin905dd707f2016-10-27 10:36:06 +01002007 /*
2008 * Ignore going modules since it's possible that ro
2009 * protection has already been disabled, otherwise we'll
2010 * run into protection faults at module deallocation.
2011 */
2012 if (mod->state == MODULE_STATE_UNFORMED ||
2013 mod->state == MODULE_STATE_GOING)
Rusty Russell0d21b0e2013-01-12 11:38:44 +10302014 continue;
Rusty Russell85c898d2015-11-26 09:45:08 +10302015
2016 frob_text(&mod->core_layout, set_memory_ro);
2017 frob_text(&mod->init_layout, set_memory_ro);
matthieu castet84e1c6b2010-11-16 22:35:16 +01002018 }
2019 mutex_unlock(&module_mutex);
2020}
Rusty Russell85c898d2015-11-26 09:45:08 +10302021
2022static void disable_ro_nx(const struct module_layout *layout)
2023{
AKASHI Takahiro39290b32016-11-14 15:15:05 +09002024 if (rodata_enabled) {
2025 frob_text(layout, set_memory_rw);
2026 frob_rodata(layout, set_memory_rw);
2027 frob_ro_after_init(layout, set_memory_rw);
2028 }
Rusty Russell85c898d2015-11-26 09:45:08 +10302029 frob_rodata(layout, set_memory_x);
Jessica Yu444d13f2016-07-27 12:06:21 +09302030 frob_ro_after_init(layout, set_memory_x);
Rusty Russell85c898d2015-11-26 09:45:08 +10302031 frob_writable_data(layout, set_memory_x);
2032}
2033
matthieu castet84e1c6b2010-11-16 22:35:16 +01002034#else
Rusty Russell85c898d2015-11-26 09:45:08 +10302035static void disable_ro_nx(const struct module_layout *layout) { }
2036static void module_enable_nx(const struct module *mod) { }
2037static void module_disable_nx(const struct module *mod) { }
matthieu castet84e1c6b2010-11-16 22:35:16 +01002038#endif
2039
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002040#ifdef CONFIG_LIVEPATCH
2041/*
2042 * Persist Elf information about a module. Copy the Elf header,
2043 * section header table, section string table, and symtab section
2044 * index from info to mod->klp_info.
2045 */
2046static int copy_module_elf(struct module *mod, struct load_info *info)
2047{
2048 unsigned int size, symndx;
2049 int ret;
2050
2051 size = sizeof(*mod->klp_info);
2052 mod->klp_info = kmalloc(size, GFP_KERNEL);
2053 if (mod->klp_info == NULL)
2054 return -ENOMEM;
2055
2056 /* Elf header */
2057 size = sizeof(mod->klp_info->hdr);
2058 memcpy(&mod->klp_info->hdr, info->hdr, size);
2059
2060 /* Elf section header table */
2061 size = sizeof(*info->sechdrs) * info->hdr->e_shnum;
2062 mod->klp_info->sechdrs = kmalloc(size, GFP_KERNEL);
2063 if (mod->klp_info->sechdrs == NULL) {
2064 ret = -ENOMEM;
2065 goto free_info;
2066 }
2067 memcpy(mod->klp_info->sechdrs, info->sechdrs, size);
2068
2069 /* Elf section name string table */
2070 size = info->sechdrs[info->hdr->e_shstrndx].sh_size;
2071 mod->klp_info->secstrings = kmalloc(size, GFP_KERNEL);
2072 if (mod->klp_info->secstrings == NULL) {
2073 ret = -ENOMEM;
2074 goto free_sechdrs;
2075 }
2076 memcpy(mod->klp_info->secstrings, info->secstrings, size);
2077
2078 /* Elf symbol section index */
2079 symndx = info->index.sym;
2080 mod->klp_info->symndx = symndx;
2081
2082 /*
2083 * For livepatch modules, core_kallsyms.symtab is a complete
2084 * copy of the original symbol table. Adjust sh_addr to point
2085 * to core_kallsyms.symtab since the copy of the symtab in module
2086 * init memory is freed at the end of do_init_module().
2087 */
2088 mod->klp_info->sechdrs[symndx].sh_addr = \
2089 (unsigned long) mod->core_kallsyms.symtab;
2090
2091 return 0;
2092
2093free_sechdrs:
2094 kfree(mod->klp_info->sechdrs);
2095free_info:
2096 kfree(mod->klp_info);
2097 return ret;
2098}
2099
2100static void free_module_elf(struct module *mod)
2101{
2102 kfree(mod->klp_info->sechdrs);
2103 kfree(mod->klp_info->secstrings);
2104 kfree(mod->klp_info);
2105}
2106#else /* !CONFIG_LIVEPATCH */
2107static int copy_module_elf(struct module *mod, struct load_info *info)
2108{
2109 return 0;
2110}
2111
2112static void free_module_elf(struct module *mod)
2113{
2114}
2115#endif /* CONFIG_LIVEPATCH */
2116
Rusty Russellbe1f2212015-01-20 09:07:05 +10302117void __weak module_memfree(void *module_region)
Jonas Bonn74e08fc2011-06-30 21:22:11 +02002118{
2119 vfree(module_region);
2120}
2121
2122void __weak module_arch_cleanup(struct module *mod)
2123{
2124}
2125
Rusty Russelld453cde2015-01-20 09:07:04 +10302126void __weak module_arch_freeing_init(struct module *mod)
2127{
2128}
2129
Rusty Russell75676502010-06-05 11:17:36 -06002130/* Free a module, remove from lists, etc. */
Linus Torvalds1da177e2005-04-16 15:20:36 -07002131static void free_module(struct module *mod)
2132{
Li Zefan7ead8b82009-08-17 16:56:28 +08002133 trace_module_free(mod);
2134
Rusty Russell36b03602010-08-05 12:59:09 -06002135 mod_sysfs_teardown(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002136
Rusty Russell944a1fa2013-04-17 13:20:03 +09302137 /* We leave it in list to prevent duplicate loads, but make sure
2138 * that noone uses it while it's being deconstructed. */
Prarit Bhargavad3051b42014-10-14 02:51:39 +10302139 mutex_lock(&module_mutex);
Rusty Russell944a1fa2013-04-17 13:20:03 +09302140 mod->state = MODULE_STATE_UNFORMED;
Prarit Bhargavad3051b42014-10-14 02:51:39 +10302141 mutex_unlock(&module_mutex);
Rusty Russell944a1fa2013-04-17 13:20:03 +09302142
Jason Baronb82bab4b2010-07-27 13:18:01 -07002143 /* Remove dynamic debug info */
2144 ddebug_remove_module(mod->name);
2145
Linus Torvalds1da177e2005-04-16 15:20:36 -07002146 /* Arch-specific cleanup. */
2147 module_arch_cleanup(mod);
2148
2149 /* Module unload stuff */
2150 module_unload_free(mod);
2151
Rusty Russelle180a6b2009-03-31 13:05:29 -06002152 /* Free any allocated parameters. */
2153 destroy_params(mod->kp, mod->num_kp);
2154
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002155 if (is_livepatch_module(mod))
2156 free_module_elf(mod);
2157
Rusty Russell944a1fa2013-04-17 13:20:03 +09302158 /* Now we can delete it from the lists */
2159 mutex_lock(&module_mutex);
Masami Hiramatsu461e34a2014-11-10 09:27:29 +10302160 /* Unlink carefully: kallsyms could be walking list. */
2161 list_del_rcu(&mod->list);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09302162 mod_tree_remove(mod);
Masami Hiramatsu0286b5e2014-11-10 09:28:29 +10302163 /* Remove this module from bug list, this uses list_del_rcu */
Masami Hiramatsu461e34a2014-11-10 09:27:29 +10302164 module_bug_cleanup(mod);
Peter Zijlstra0be964b2015-05-27 11:09:35 +09302165 /* Wait for RCU-sched synchronizing before releasing mod->list and buglist. */
2166 synchronize_sched();
Rusty Russell944a1fa2013-04-17 13:20:03 +09302167 mutex_unlock(&module_mutex);
2168
Rusty Russell85c898d2015-11-26 09:45:08 +10302169 /* This may be empty, but that's OK */
2170 disable_ro_nx(&mod->init_layout);
Rusty Russelld453cde2015-01-20 09:07:04 +10302171 module_arch_freeing_init(mod);
Rusty Russell7523e4d2015-11-26 09:44:08 +10302172 module_memfree(mod->init_layout.base);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002173 kfree(mod->args);
Tejun Heo259354d2010-03-10 18:56:10 +09002174 percpu_modfree(mod);
Rusty Russell9f85a4b2010-08-05 12:59:04 -06002175
Peter Zijlstra35a93932015-02-26 16:23:11 +01002176 /* Free lock-classes; relies on the preceding sync_rcu(). */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302177 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
Ingo Molnarfbb9ce952006-07-03 00:24:50 -07002178
Linus Torvalds1da177e2005-04-16 15:20:36 -07002179 /* Finally, free the core (containing the module structure) */
Rusty Russell85c898d2015-11-26 09:45:08 +10302180 disable_ro_nx(&mod->core_layout);
Rusty Russell7523e4d2015-11-26 09:44:08 +10302181 module_memfree(mod->core_layout.base);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002182}
2183
2184void *__symbol_get(const char *symbol)
2185{
2186 struct module *owner;
Tim Abbott414fd312008-12-05 19:03:56 -05002187 const struct kernel_symbol *sym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002188
Rusty Russell24da1cb2007-07-15 23:41:46 -07002189 preempt_disable();
Tim Abbott414fd312008-12-05 19:03:56 -05002190 sym = find_symbol(symbol, &owner, NULL, true, true);
2191 if (sym && strong_try_module_get(owner))
2192 sym = NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07002193 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07002194
Tim Abbott414fd312008-12-05 19:03:56 -05002195 return sym ? (void *)sym->value : NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002196}
2197EXPORT_SYMBOL_GPL(__symbol_get);
2198
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002199/*
2200 * Ensure that an exported symbol [global namespace] does not already exist
Robert P. J. Day02a3e592007-05-09 07:26:28 +02002201 * in the kernel or in some other module's exported symbol table.
Rusty Russellbe593f42010-06-05 11:17:37 -06002202 *
2203 * You must hold the module_mutex.
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002204 */
2205static int verify_export_symbols(struct module *mod)
2206{
Rusty Russellb2111042008-05-01 21:15:00 -05002207 unsigned int i;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002208 struct module *owner;
Rusty Russellb2111042008-05-01 21:15:00 -05002209 const struct kernel_symbol *s;
2210 struct {
2211 const struct kernel_symbol *sym;
2212 unsigned int num;
2213 } arr[] = {
2214 { mod->syms, mod->num_syms },
2215 { mod->gpl_syms, mod->num_gpl_syms },
2216 { mod->gpl_future_syms, mod->num_gpl_future_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002217#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russellb2111042008-05-01 21:15:00 -05002218 { mod->unused_syms, mod->num_unused_syms },
2219 { mod->unused_gpl_syms, mod->num_unused_gpl_syms },
Denys Vlasenkof7f5b672008-07-22 19:24:26 -05002220#endif
Rusty Russellb2111042008-05-01 21:15:00 -05002221 };
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002222
Rusty Russellb2111042008-05-01 21:15:00 -05002223 for (i = 0; i < ARRAY_SIZE(arr); i++) {
2224 for (s = arr[i].sym; s < arr[i].sym + arr[i].num; s++) {
Rusty Russellbe593f42010-06-05 11:17:37 -06002225 if (find_symbol(s->name, &owner, NULL, true, false)) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002226 pr_err("%s: exports duplicate symbol %s"
Rusty Russellb2111042008-05-01 21:15:00 -05002227 " (owned by %s)\n",
2228 mod->name, s->name, module_name(owner));
2229 return -ENOEXEC;
2230 }
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002231 }
Rusty Russellb2111042008-05-01 21:15:00 -05002232 }
2233 return 0;
Ashutosh Naikeea8b542006-01-08 01:04:25 -08002234}
2235
Matti Linnanvuori9a4b9702007-11-08 08:37:38 -08002236/* Change all symbols so that st_value encodes the pointer directly. */
Rusty Russell49668682010-08-05 12:59:10 -06002237static int simplify_symbols(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002238{
Rusty Russell49668682010-08-05 12:59:10 -06002239 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
2240 Elf_Sym *sym = (void *)symsec->sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002241 unsigned long secbase;
Rusty Russell49668682010-08-05 12:59:10 -06002242 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002243 int ret = 0;
Tim Abbott414fd312008-12-05 19:03:56 -05002244 const struct kernel_symbol *ksym;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002245
Rusty Russell49668682010-08-05 12:59:10 -06002246 for (i = 1; i < symsec->sh_size / sizeof(Elf_Sym); i++) {
2247 const char *name = info->strtab + sym[i].st_name;
2248
Linus Torvalds1da177e2005-04-16 15:20:36 -07002249 switch (sym[i].st_shndx) {
2250 case SHN_COMMON:
Joe Mario80375982014-02-08 09:01:09 +01002251 /* Ignore common symbols */
2252 if (!strncmp(name, "__gnu_lto", 9))
2253 break;
2254
Linus Torvalds1da177e2005-04-16 15:20:36 -07002255 /* We compiled with -fno-common. These are not
2256 supposed to happen. */
Jim Cromie5e124162011-12-06 12:11:31 -07002257 pr_debug("Common symbol: %s\n", name);
Ionut Alexa6da0b562014-11-10 09:31:29 +10302258 pr_warn("%s: please compile with -fno-common\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002259 mod->name);
2260 ret = -ENOEXEC;
2261 break;
2262
2263 case SHN_ABS:
2264 /* Don't need to do anything */
Jim Cromie5e124162011-12-06 12:11:31 -07002265 pr_debug("Absolute symbol: 0x%08lx\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -07002266 (long)sym[i].st_value);
2267 break;
2268
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002269 case SHN_LIVEPATCH:
2270 /* Livepatch symbols are resolved by livepatch */
2271 break;
2272
Linus Torvalds1da177e2005-04-16 15:20:36 -07002273 case SHN_UNDEF:
Rusty Russell49668682010-08-05 12:59:10 -06002274 ksym = resolve_symbol_wait(mod, info, name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002275 /* Ok if resolved. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06002276 if (ksym && !IS_ERR(ksym)) {
Tim Abbott414fd312008-12-05 19:03:56 -05002277 sym[i].st_value = ksym->value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002278 break;
Tim Abbott414fd312008-12-05 19:03:56 -05002279 }
2280
Linus Torvalds1da177e2005-04-16 15:20:36 -07002281 /* Ok if weak. */
Rusty Russell9bea7f22010-06-05 11:17:37 -06002282 if (!ksym && ELF_ST_BIND(sym[i].st_info) == STB_WEAK)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002283 break;
2284
Rusty Russell9bea7f22010-06-05 11:17:37 -06002285 ret = PTR_ERR(ksym) ?: -ENOENT;
Jason A. Donenfeld62267e02018-06-22 17:38:50 +02002286 pr_warn("%s: Unknown symbol %s (err %d)\n",
2287 mod->name, name, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002288 break;
2289
2290 default:
2291 /* Divert to percpu allocation if a percpu var. */
Rusty Russell49668682010-08-05 12:59:10 -06002292 if (sym[i].st_shndx == info->index.pcpu)
Tejun Heo259354d2010-03-10 18:56:10 +09002293 secbase = (unsigned long)mod_percpu(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002294 else
Rusty Russell49668682010-08-05 12:59:10 -06002295 secbase = info->sechdrs[sym[i].st_shndx].sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002296 sym[i].st_value += secbase;
2297 break;
2298 }
2299 }
2300
2301 return ret;
2302}
2303
Rusty Russell49668682010-08-05 12:59:10 -06002304static int apply_relocations(struct module *mod, const struct load_info *info)
Rusty Russell22e268e2010-08-05 12:59:05 -06002305{
2306 unsigned int i;
2307 int err = 0;
2308
2309 /* Now do relocations. */
Rusty Russell49668682010-08-05 12:59:10 -06002310 for (i = 1; i < info->hdr->e_shnum; i++) {
2311 unsigned int infosec = info->sechdrs[i].sh_info;
Rusty Russell22e268e2010-08-05 12:59:05 -06002312
2313 /* Not a valid relocation section? */
Rusty Russell49668682010-08-05 12:59:10 -06002314 if (infosec >= info->hdr->e_shnum)
Rusty Russell22e268e2010-08-05 12:59:05 -06002315 continue;
2316
2317 /* Don't bother with non-allocated sections */
Rusty Russell49668682010-08-05 12:59:10 -06002318 if (!(info->sechdrs[infosec].sh_flags & SHF_ALLOC))
Rusty Russell22e268e2010-08-05 12:59:05 -06002319 continue;
2320
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002321 /* Livepatch relocation sections are applied by livepatch */
2322 if (info->sechdrs[i].sh_flags & SHF_RELA_LIVEPATCH)
2323 continue;
2324
Rusty Russell49668682010-08-05 12:59:10 -06002325 if (info->sechdrs[i].sh_type == SHT_REL)
2326 err = apply_relocate(info->sechdrs, info->strtab,
2327 info->index.sym, i, mod);
2328 else if (info->sechdrs[i].sh_type == SHT_RELA)
2329 err = apply_relocate_add(info->sechdrs, info->strtab,
2330 info->index.sym, i, mod);
Rusty Russell22e268e2010-08-05 12:59:05 -06002331 if (err < 0)
2332 break;
2333 }
2334 return err;
2335}
2336
Helge Deller088af9a2008-12-31 12:31:18 +01002337/* Additional bytes needed by arch in front of individual sections */
2338unsigned int __weak arch_mod_section_prepend(struct module *mod,
2339 unsigned int section)
2340{
2341 /* default implementation just returns zero */
2342 return 0;
2343}
2344
Linus Torvalds1da177e2005-04-16 15:20:36 -07002345/* Update size with this section: return offset. */
Helge Deller088af9a2008-12-31 12:31:18 +01002346static long get_offset(struct module *mod, unsigned int *size,
2347 Elf_Shdr *sechdr, unsigned int section)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002348{
2349 long ret;
2350
Helge Deller088af9a2008-12-31 12:31:18 +01002351 *size += arch_mod_section_prepend(mod, section);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002352 ret = ALIGN(*size, sechdr->sh_addralign ?: 1);
2353 *size = ret + sechdr->sh_size;
2354 return ret;
2355}
2356
2357/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
2358 might -- code, read-only data, read-write data, small data. Tally
2359 sizes, and place the offsets into sh_entsize fields: high bit means it
2360 belongs in init. */
Rusty Russell49668682010-08-05 12:59:10 -06002361static void layout_sections(struct module *mod, struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002362{
2363 static unsigned long const masks[][2] = {
2364 /* NOTE: all executable code must be the first section
2365 * in this array; otherwise modify the text_size
2366 * finder in the two loops below */
2367 { SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL },
2368 { SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL },
Jessica Yu444d13f2016-07-27 12:06:21 +09302369 { SHF_RO_AFTER_INIT | SHF_ALLOC, ARCH_SHF_SMALL },
Linus Torvalds1da177e2005-04-16 15:20:36 -07002370 { SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL },
2371 { ARCH_SHF_SMALL | SHF_ALLOC, 0 }
2372 };
2373 unsigned int m, i;
2374
Rusty Russell49668682010-08-05 12:59:10 -06002375 for (i = 0; i < info->hdr->e_shnum; i++)
2376 info->sechdrs[i].sh_entsize = ~0UL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002377
Jim Cromie5e124162011-12-06 12:11:31 -07002378 pr_debug("Core section allocation order:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002379 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
Rusty Russell49668682010-08-05 12:59:10 -06002380 for (i = 0; i < info->hdr->e_shnum; ++i) {
2381 Elf_Shdr *s = &info->sechdrs[i];
2382 const char *sname = info->secstrings + s->sh_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002383
2384 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2385 || (s->sh_flags & masks[m][1])
2386 || s->sh_entsize != ~0UL
Rusty Russell49668682010-08-05 12:59:10 -06002387 || strstarts(sname, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002388 continue;
Rusty Russell7523e4d2015-11-26 09:44:08 +10302389 s->sh_entsize = get_offset(mod, &mod->core_layout.size, s, i);
Jim Cromie5e124162011-12-06 12:11:31 -07002390 pr_debug("\t%s\n", sname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002391 }
matthieu castet84e1c6b2010-11-16 22:35:16 +01002392 switch (m) {
2393 case 0: /* executable */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302394 mod->core_layout.size = debug_align(mod->core_layout.size);
2395 mod->core_layout.text_size = mod->core_layout.size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002396 break;
2397 case 1: /* RO: text and ro-data */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302398 mod->core_layout.size = debug_align(mod->core_layout.size);
2399 mod->core_layout.ro_size = mod->core_layout.size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002400 break;
Jessica Yu444d13f2016-07-27 12:06:21 +09302401 case 2: /* RO after init */
2402 mod->core_layout.size = debug_align(mod->core_layout.size);
2403 mod->core_layout.ro_after_init_size = mod->core_layout.size;
2404 break;
2405 case 4: /* whole core */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302406 mod->core_layout.size = debug_align(mod->core_layout.size);
matthieu castet84e1c6b2010-11-16 22:35:16 +01002407 break;
2408 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002409 }
2410
Jim Cromie5e124162011-12-06 12:11:31 -07002411 pr_debug("Init section allocation order:\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07002412 for (m = 0; m < ARRAY_SIZE(masks); ++m) {
Rusty Russell49668682010-08-05 12:59:10 -06002413 for (i = 0; i < info->hdr->e_shnum; ++i) {
2414 Elf_Shdr *s = &info->sechdrs[i];
2415 const char *sname = info->secstrings + s->sh_name;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002416
2417 if ((s->sh_flags & masks[m][0]) != masks[m][0]
2418 || (s->sh_flags & masks[m][1])
2419 || s->sh_entsize != ~0UL
Rusty Russell49668682010-08-05 12:59:10 -06002420 || !strstarts(sname, ".init"))
Linus Torvalds1da177e2005-04-16 15:20:36 -07002421 continue;
Rusty Russell7523e4d2015-11-26 09:44:08 +10302422 s->sh_entsize = (get_offset(mod, &mod->init_layout.size, s, i)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002423 | INIT_OFFSET_MASK);
Jim Cromie5e124162011-12-06 12:11:31 -07002424 pr_debug("\t%s\n", sname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002425 }
matthieu castet84e1c6b2010-11-16 22:35:16 +01002426 switch (m) {
2427 case 0: /* executable */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302428 mod->init_layout.size = debug_align(mod->init_layout.size);
2429 mod->init_layout.text_size = mod->init_layout.size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002430 break;
2431 case 1: /* RO: text and ro-data */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302432 mod->init_layout.size = debug_align(mod->init_layout.size);
2433 mod->init_layout.ro_size = mod->init_layout.size;
matthieu castet84e1c6b2010-11-16 22:35:16 +01002434 break;
Jessica Yu444d13f2016-07-27 12:06:21 +09302435 case 2:
2436 /*
2437 * RO after init doesn't apply to init_layout (only
2438 * core_layout), so it just takes the value of ro_size.
2439 */
2440 mod->init_layout.ro_after_init_size = mod->init_layout.ro_size;
2441 break;
2442 case 4: /* whole init */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302443 mod->init_layout.size = debug_align(mod->init_layout.size);
matthieu castet84e1c6b2010-11-16 22:35:16 +01002444 break;
2445 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002446 }
2447}
2448
Linus Torvalds1da177e2005-04-16 15:20:36 -07002449static void set_license(struct module *mod, const char *license)
2450{
2451 if (!license)
2452 license = "unspecified";
2453
Florin Malitafa3ba2e82006-10-11 01:21:48 -07002454 if (!license_is_gpl_compatible(license)) {
Andi Kleen25ddbb12008-10-15 22:01:41 -07002455 if (!test_taint(TAINT_PROPRIETARY_MODULE))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002456 pr_warn("%s: module license '%s' taints kernel.\n",
2457 mod->name, license);
Rusty Russell373d4d02013-01-21 17:17:39 +10302458 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
2459 LOCKDEP_NOW_UNRELIABLE);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002460 }
2461}
2462
2463/* Parse tag=value strings from .modinfo section */
2464static char *next_string(char *string, unsigned long *secsize)
2465{
2466 /* Skip non-zero chars */
2467 while (string[0]) {
2468 string++;
2469 if ((*secsize)-- <= 1)
2470 return NULL;
2471 }
2472
2473 /* Skip any zero padding. */
2474 while (!string[0]) {
2475 string++;
2476 if ((*secsize)-- <= 1)
2477 return NULL;
2478 }
2479 return string;
2480}
2481
Rusty Russell49668682010-08-05 12:59:10 -06002482static char *get_modinfo(struct load_info *info, const char *tag)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002483{
2484 char *p;
2485 unsigned int taglen = strlen(tag);
Rusty Russell49668682010-08-05 12:59:10 -06002486 Elf_Shdr *infosec = &info->sechdrs[info->index.info];
2487 unsigned long size = infosec->sh_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002488
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002489 /*
2490 * get_modinfo() calls made before rewrite_section_headers()
2491 * must use sh_offset, as sh_addr isn't set!
2492 */
2493 for (p = (char *)info->hdr + infosec->sh_offset; p; p = next_string(p, &size)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002494 if (strncmp(p, tag, taglen) == 0 && p[taglen] == '=')
2495 return p + taglen + 1;
2496 }
2497 return NULL;
2498}
2499
Rusty Russell49668682010-08-05 12:59:10 -06002500static void setup_modinfo(struct module *mod, struct load_info *info)
Matt Domschc988d2b2005-06-23 22:05:15 -07002501{
2502 struct module_attribute *attr;
2503 int i;
2504
2505 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2506 if (attr->setup)
Rusty Russell49668682010-08-05 12:59:10 -06002507 attr->setup(mod, get_modinfo(info, attr->attr.name));
Matt Domschc988d2b2005-06-23 22:05:15 -07002508 }
2509}
Matt Domschc988d2b2005-06-23 22:05:15 -07002510
Rusty Russella263f7762009-09-25 00:32:58 -06002511static void free_modinfo(struct module *mod)
2512{
2513 struct module_attribute *attr;
2514 int i;
2515
2516 for (i = 0; (attr = modinfo_attrs[i]); i++) {
2517 if (attr->free)
2518 attr->free(mod);
2519 }
2520}
2521
Linus Torvalds1da177e2005-04-16 15:20:36 -07002522#ifdef CONFIG_KALLSYMS
WANG Cong15bba372008-07-24 15:41:48 +01002523
2524/* lookup symbol in given range of kernel_symbols */
2525static const struct kernel_symbol *lookup_symbol(const char *name,
2526 const struct kernel_symbol *start,
2527 const struct kernel_symbol *stop)
2528{
Alessio Igor Bogani9d634872011-05-18 22:35:59 +02002529 return bsearch(name, start, stop - start,
2530 sizeof(struct kernel_symbol), cmp_name);
WANG Cong15bba372008-07-24 15:41:48 +01002531}
2532
Tim Abbottca4787b2009-01-05 08:40:10 -06002533static int is_exported(const char *name, unsigned long value,
2534 const struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002535{
Tim Abbottca4787b2009-01-05 08:40:10 -06002536 const struct kernel_symbol *ks;
2537 if (!mod)
2538 ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
Sam Ravnborg3fd68052006-02-08 21:16:45 +01002539 else
Tim Abbottca4787b2009-01-05 08:40:10 -06002540 ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
2541 return ks != NULL && ks->value == value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002542}
2543
2544/* As per nm */
Rusty Russelleded41c2010-08-05 12:59:07 -06002545static char elf_type(const Elf_Sym *sym, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002546{
Rusty Russelleded41c2010-08-05 12:59:07 -06002547 const Elf_Shdr *sechdrs = info->sechdrs;
2548
Linus Torvalds1da177e2005-04-16 15:20:36 -07002549 if (ELF_ST_BIND(sym->st_info) == STB_WEAK) {
2550 if (ELF_ST_TYPE(sym->st_info) == STT_OBJECT)
2551 return 'v';
2552 else
2553 return 'w';
2554 }
2555 if (sym->st_shndx == SHN_UNDEF)
2556 return 'U';
Miroslav Benese0224412015-11-26 13:18:06 +10302557 if (sym->st_shndx == SHN_ABS || sym->st_shndx == info->index.pcpu)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002558 return 'a';
2559 if (sym->st_shndx >= SHN_LORESERVE)
2560 return '?';
2561 if (sechdrs[sym->st_shndx].sh_flags & SHF_EXECINSTR)
2562 return 't';
2563 if (sechdrs[sym->st_shndx].sh_flags & SHF_ALLOC
2564 && sechdrs[sym->st_shndx].sh_type != SHT_NOBITS) {
2565 if (!(sechdrs[sym->st_shndx].sh_flags & SHF_WRITE))
2566 return 'r';
2567 else if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2568 return 'g';
2569 else
2570 return 'd';
2571 }
2572 if (sechdrs[sym->st_shndx].sh_type == SHT_NOBITS) {
2573 if (sechdrs[sym->st_shndx].sh_flags & ARCH_SHF_SMALL)
2574 return 's';
2575 else
2576 return 'b';
2577 }
Rusty Russelleded41c2010-08-05 12:59:07 -06002578 if (strstarts(info->secstrings + sechdrs[sym->st_shndx].sh_name,
2579 ".debug")) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07002580 return 'n';
Rusty Russelleded41c2010-08-05 12:59:07 -06002581 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07002582 return '?';
2583}
2584
Jan Beulich4a496222009-07-06 14:50:42 +01002585static bool is_core_symbol(const Elf_Sym *src, const Elf_Shdr *sechdrs,
Miroslav Benese0224412015-11-26 13:18:06 +10302586 unsigned int shnum, unsigned int pcpundx)
Jan Beulich4a496222009-07-06 14:50:42 +01002587{
2588 const Elf_Shdr *sec;
2589
2590 if (src->st_shndx == SHN_UNDEF
2591 || src->st_shndx >= shnum
2592 || !src->st_name)
2593 return false;
2594
Miroslav Benese0224412015-11-26 13:18:06 +10302595#ifdef CONFIG_KALLSYMS_ALL
2596 if (src->st_shndx == pcpundx)
2597 return true;
2598#endif
2599
Jan Beulich4a496222009-07-06 14:50:42 +01002600 sec = sechdrs + src->st_shndx;
2601 if (!(sec->sh_flags & SHF_ALLOC)
2602#ifndef CONFIG_KALLSYMS_ALL
2603 || !(sec->sh_flags & SHF_EXECINSTR)
2604#endif
2605 || (sec->sh_entsize & INIT_OFFSET_MASK))
2606 return false;
2607
2608 return true;
2609}
2610
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302611/*
2612 * We only allocate and copy the strings needed by the parts of symtab
2613 * we keep. This is simple, but has the effect of making multiple
2614 * copies of duplicates. We could be more sophisticated, see
2615 * linux-kernel thread starting with
2616 * <73defb5e4bca04a6431392cc341112b1@localhost>.
2617 */
Rusty Russell49668682010-08-05 12:59:10 -06002618static void layout_symtab(struct module *mod, struct load_info *info)
Jan Beulich4a496222009-07-06 14:50:42 +01002619{
Rusty Russell49668682010-08-05 12:59:10 -06002620 Elf_Shdr *symsect = info->sechdrs + info->index.sym;
2621 Elf_Shdr *strsect = info->sechdrs + info->index.str;
Jan Beulich4a496222009-07-06 14:50:42 +01002622 const Elf_Sym *src;
Satoru Takeuchi54523ec2012-12-05 12:29:04 +10302623 unsigned int i, nsrc, ndst, strtab_size = 0;
Jan Beulich4a496222009-07-06 14:50:42 +01002624
2625 /* Put symbol section at end of init part of module. */
2626 symsect->sh_flags |= SHF_ALLOC;
Rusty Russell7523e4d2015-11-26 09:44:08 +10302627 symsect->sh_entsize = get_offset(mod, &mod->init_layout.size, symsect,
Rusty Russell49668682010-08-05 12:59:10 -06002628 info->index.sym) | INIT_OFFSET_MASK;
Jim Cromie5e124162011-12-06 12:11:31 -07002629 pr_debug("\t%s\n", info->secstrings + symsect->sh_name);
Jan Beulich4a496222009-07-06 14:50:42 +01002630
Rusty Russell49668682010-08-05 12:59:10 -06002631 src = (void *)info->hdr + symsect->sh_offset;
Jan Beulich4a496222009-07-06 14:50:42 +01002632 nsrc = symsect->sh_size / sizeof(*src);
Kevin Cernekee70b1e9162011-11-12 19:08:55 -08002633
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302634 /* Compute total space required for the core symbols' strtab. */
Rusty Russell59ef28b2012-10-25 10:49:25 +10302635 for (ndst = i = 0; i < nsrc; i++) {
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002636 if (i == 0 || is_livepatch_module(mod) ||
Miroslav Benese0224412015-11-26 13:18:06 +10302637 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2638 info->index.pcpu)) {
Rusty Russell59ef28b2012-10-25 10:49:25 +10302639 strtab_size += strlen(&info->strtab[src[i].st_name])+1;
Kevin Cernekee48fd1182012-01-13 09:32:14 +10302640 ndst++;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002641 }
Rusty Russell59ef28b2012-10-25 10:49:25 +10302642 }
Jan Beulich4a496222009-07-06 14:50:42 +01002643
2644 /* Append room for core symbols at end of core part. */
Rusty Russell7523e4d2015-11-26 09:44:08 +10302645 info->symoffs = ALIGN(mod->core_layout.size, symsect->sh_addralign ?: 1);
2646 info->stroffs = mod->core_layout.size = info->symoffs + ndst * sizeof(Elf_Sym);
2647 mod->core_layout.size += strtab_size;
2648 mod->core_layout.size = debug_align(mod->core_layout.size);
Jan Beulich4a496222009-07-06 14:50:42 +01002649
Jan Beulich554bdfe2009-07-06 14:51:44 +01002650 /* Put string table section at end of init part of module. */
2651 strsect->sh_flags |= SHF_ALLOC;
Rusty Russell7523e4d2015-11-26 09:44:08 +10302652 strsect->sh_entsize = get_offset(mod, &mod->init_layout.size, strsect,
Rusty Russell49668682010-08-05 12:59:10 -06002653 info->index.str) | INIT_OFFSET_MASK;
Jim Cromie5e124162011-12-06 12:11:31 -07002654 pr_debug("\t%s\n", info->secstrings + strsect->sh_name);
Rusty Russell82440622016-02-03 16:55:26 +10302655
2656 /* We'll tack temporary mod_kallsyms on the end. */
2657 mod->init_layout.size = ALIGN(mod->init_layout.size,
2658 __alignof__(struct mod_kallsyms));
2659 info->mod_kallsyms_init_off = mod->init_layout.size;
2660 mod->init_layout.size += sizeof(struct mod_kallsyms);
2661 mod->init_layout.size = debug_align(mod->init_layout.size);
Jan Beulich4a496222009-07-06 14:50:42 +01002662}
2663
Rusty Russell82440622016-02-03 16:55:26 +10302664/*
2665 * We use the full symtab and strtab which layout_symtab arranged to
2666 * be appended to the init section. Later we switch to the cut-down
2667 * core-only ones.
2668 */
Rusty Russell811d66a2010-08-05 12:59:12 -06002669static void add_kallsyms(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002670{
Jan Beulich4a496222009-07-06 14:50:42 +01002671 unsigned int i, ndst;
2672 const Elf_Sym *src;
2673 Elf_Sym *dst;
Jan Beulich554bdfe2009-07-06 14:51:44 +01002674 char *s;
Rusty Russelleded41c2010-08-05 12:59:07 -06002675 Elf_Shdr *symsec = &info->sechdrs[info->index.sym];
Linus Torvalds1da177e2005-04-16 15:20:36 -07002676
Rusty Russell82440622016-02-03 16:55:26 +10302677 /* Set up to point into init section. */
2678 mod->kallsyms = mod->init_layout.base + info->mod_kallsyms_init_off;
2679
2680 mod->kallsyms->symtab = (void *)symsec->sh_addr;
2681 mod->kallsyms->num_symtab = symsec->sh_size / sizeof(Elf_Sym);
Rusty Russell511ca6a2010-08-05 12:59:08 -06002682 /* Make sure we get permanent strtab: don't use info->strtab. */
Rusty Russell82440622016-02-03 16:55:26 +10302683 mod->kallsyms->strtab = (void *)info->sechdrs[info->index.str].sh_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002684
2685 /* Set types up while we still have access to sections. */
Rusty Russell82440622016-02-03 16:55:26 +10302686 for (i = 0; i < mod->kallsyms->num_symtab; i++)
2687 mod->kallsyms->symtab[i].st_info
2688 = elf_type(&mod->kallsyms->symtab[i], info);
Jan Beulich4a496222009-07-06 14:50:42 +01002689
Rusty Russell82440622016-02-03 16:55:26 +10302690 /* Now populate the cut down core kallsyms for after init. */
2691 mod->core_kallsyms.symtab = dst = mod->core_layout.base + info->symoffs;
2692 mod->core_kallsyms.strtab = s = mod->core_layout.base + info->stroffs;
2693 src = mod->kallsyms->symtab;
2694 for (ndst = i = 0; i < mod->kallsyms->num_symtab; i++) {
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002695 if (i == 0 || is_livepatch_module(mod) ||
Miroslav Benese0224412015-11-26 13:18:06 +10302696 is_core_symbol(src+i, info->sechdrs, info->hdr->e_shnum,
2697 info->index.pcpu)) {
Rusty Russell59ef28b2012-10-25 10:49:25 +10302698 dst[ndst] = src[i];
Rusty Russell82440622016-02-03 16:55:26 +10302699 dst[ndst++].st_name = s - mod->core_kallsyms.strtab;
2700 s += strlcpy(s, &mod->kallsyms->strtab[src[i].st_name],
Rusty Russell59ef28b2012-10-25 10:49:25 +10302701 KSYM_NAME_LEN) + 1;
2702 }
Jan Beulich4a496222009-07-06 14:50:42 +01002703 }
Rusty Russell82440622016-02-03 16:55:26 +10302704 mod->core_kallsyms.num_symtab = ndst;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002705}
2706#else
Rusty Russell49668682010-08-05 12:59:10 -06002707static inline void layout_symtab(struct module *mod, struct load_info *info)
Jan Beulich4a496222009-07-06 14:50:42 +01002708{
2709}
Paul Mundt3ae91c22009-10-01 15:43:54 -07002710
Michał Mirosławabbce902010-09-20 01:58:08 +02002711static void add_kallsyms(struct module *mod, const struct load_info *info)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002712{
2713}
2714#endif /* CONFIG_KALLSYMS */
2715
Zhou Chengming52796312017-07-07 11:15:58 +08002716static void dynamic_debug_setup(struct module *mod, struct _ddebug *debug, unsigned int num)
Rusty Russell5e458cc2008-10-22 10:00:13 -05002717{
Rusty Russell811d66a2010-08-05 12:59:12 -06002718 if (!debug)
2719 return;
Jason Barone9d376f2009-02-05 11:51:38 -05002720#ifdef CONFIG_DYNAMIC_DEBUG
Zhou Chengming52796312017-07-07 11:15:58 +08002721 if (ddebug_add_module(debug, num, mod->name))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002722 pr_err("dynamic debug error adding module: %s\n",
2723 debug->modname);
Jason Barone9d376f2009-02-05 11:51:38 -05002724#endif
Rusty Russell5e458cc2008-10-22 10:00:13 -05002725}
Jason Baron346e15b2008-08-12 16:46:19 -04002726
Zhou Chengming52796312017-07-07 11:15:58 +08002727static void dynamic_debug_remove(struct module *mod, struct _ddebug *debug)
Yehuda Sadehff49d742010-07-03 13:07:35 +10002728{
2729 if (debug)
Zhou Chengming52796312017-07-07 11:15:58 +08002730 ddebug_remove_module(mod->name);
Yehuda Sadehff49d742010-07-03 13:07:35 +10002731}
2732
Jonas Bonn74e08fc2011-06-30 21:22:11 +02002733void * __weak module_alloc(unsigned long size)
2734{
Rusty Russell82fab442012-12-11 09:38:33 +10302735 return vmalloc_exec(size);
Jonas Bonn74e08fc2011-06-30 21:22:11 +02002736}
2737
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002738#ifdef CONFIG_DEBUG_KMEMLEAK
Rusty Russell49668682010-08-05 12:59:10 -06002739static void kmemleak_load_module(const struct module *mod,
2740 const struct load_info *info)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002741{
2742 unsigned int i;
2743
2744 /* only scan the sections containing data */
Catalin Marinasc017b4be32009-10-28 13:33:09 +00002745 kmemleak_scan_area(mod, sizeof(struct module), GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002746
Rusty Russell49668682010-08-05 12:59:10 -06002747 for (i = 1; i < info->hdr->e_shnum; i++) {
Steven Rostedt06c94942013-05-15 20:33:01 +01002748 /* Scan all writable sections that's not executable */
2749 if (!(info->sechdrs[i].sh_flags & SHF_ALLOC) ||
2750 !(info->sechdrs[i].sh_flags & SHF_WRITE) ||
2751 (info->sechdrs[i].sh_flags & SHF_EXECINSTR))
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002752 continue;
2753
Rusty Russell49668682010-08-05 12:59:10 -06002754 kmemleak_scan_area((void *)info->sechdrs[i].sh_addr,
2755 info->sechdrs[i].sh_size, GFP_KERNEL);
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002756 }
2757}
2758#else
Rusty Russell49668682010-08-05 12:59:10 -06002759static inline void kmemleak_load_module(const struct module *mod,
2760 const struct load_info *info)
Catalin Marinas4f2294b2009-06-11 13:23:20 +01002761{
2762}
2763#endif
2764
Rusty Russell106a4ee2012-09-26 10:09:40 +01002765#ifdef CONFIG_MODULE_SIG
Ben Hutchingsbca014c2016-04-28 09:24:01 +09302766static int module_sig_check(struct load_info *info, int flags)
Rusty Russell106a4ee2012-09-26 10:09:40 +01002767{
2768 int err = -ENOKEY;
Kees Cook34e11692012-10-16 07:31:07 +10302769 const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
2770 const void *mod = info->hdr;
Rusty Russell106a4ee2012-09-26 10:09:40 +01002771
Ben Hutchingsbca014c2016-04-28 09:24:01 +09302772 /*
2773 * Require flags == 0, as a module with version information
2774 * removed is no longer the module that was signed
2775 */
2776 if (flags == 0 &&
2777 info->len > markerlen &&
Kees Cook34e11692012-10-16 07:31:07 +10302778 memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
David Howellscaabe242012-10-20 01:19:29 +01002779 /* We truncate the module to discard the signature */
Kees Cook34e11692012-10-16 07:31:07 +10302780 info->len -= markerlen;
2781 err = mod_verify_sig(mod, &info->len);
Rusty Russell106a4ee2012-09-26 10:09:40 +01002782 }
2783
2784 if (!err) {
2785 info->sig_ok = true;
2786 return 0;
2787 }
2788
2789 /* Not having a signature is only an error if we're strict. */
Jia Zhang2c8fd262018-04-11 11:53:33 +08002790 if (err == -ENOKEY && !is_module_sig_enforced())
Rusty Russell106a4ee2012-09-26 10:09:40 +01002791 err = 0;
2792
2793 return err;
2794}
2795#else /* !CONFIG_MODULE_SIG */
Ben Hutchingsbca014c2016-04-28 09:24:01 +09302796static int module_sig_check(struct load_info *info, int flags)
Rusty Russell106a4ee2012-09-26 10:09:40 +01002797{
2798 return 0;
2799}
2800#endif /* !CONFIG_MODULE_SIG */
2801
Kees Cook34e11692012-10-16 07:31:07 +10302802/* Sanity checks against invalid binaries, wrong arch, weird elf version. */
2803static int elf_header_check(struct load_info *info)
Rusty Russell40dd2562010-08-05 12:59:03 -06002804{
Kees Cook34e11692012-10-16 07:31:07 +10302805 if (info->len < sizeof(*(info->hdr)))
Rusty Russell40dd2562010-08-05 12:59:03 -06002806 return -ENOEXEC;
2807
Kees Cook34e11692012-10-16 07:31:07 +10302808 if (memcmp(info->hdr->e_ident, ELFMAG, SELFMAG) != 0
2809 || info->hdr->e_type != ET_REL
2810 || !elf_check_arch(info->hdr)
2811 || info->hdr->e_shentsize != sizeof(Elf_Shdr))
2812 return -ENOEXEC;
2813
2814 if (info->hdr->e_shoff >= info->len
2815 || (info->hdr->e_shnum * sizeof(Elf_Shdr) >
2816 info->len - info->hdr->e_shoff))
2817 return -ENOEXEC;
2818
2819 return 0;
2820}
2821
Linus Torvalds3afe9f82015-04-07 10:33:49 -07002822#define COPY_CHUNK_SIZE (16*PAGE_SIZE)
2823
2824static int copy_chunked_from_user(void *dst, const void __user *usrc, unsigned long len)
2825{
2826 do {
2827 unsigned long n = min(len, COPY_CHUNK_SIZE);
2828
2829 if (copy_from_user(dst, usrc, n) != 0)
2830 return -EFAULT;
2831 cond_resched();
2832 dst += n;
2833 usrc += n;
2834 len -= n;
2835 } while (len);
2836 return 0;
2837}
2838
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002839#ifdef CONFIG_LIVEPATCH
Josh Poimboeuf2992ef22016-08-25 10:04:45 -05002840static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002841{
Josh Poimboeuf2992ef22016-08-25 10:04:45 -05002842 if (get_modinfo(info, "livepatch")) {
2843 mod->klp = true;
2844 add_taint_module(mod, TAINT_LIVEPATCH, LOCKDEP_STILL_OK);
Joe Lawrence7598d162017-01-12 11:57:44 -05002845 pr_notice_once("%s: tainting kernel with TAINT_LIVEPATCH\n",
2846 mod->name);
Josh Poimboeuf2992ef22016-08-25 10:04:45 -05002847 }
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002848
2849 return 0;
2850}
2851#else /* !CONFIG_LIVEPATCH */
Josh Poimboeuf2992ef22016-08-25 10:04:45 -05002852static int check_modinfo_livepatch(struct module *mod, struct load_info *info)
Jessica Yu1ce15ef2016-03-22 20:03:16 -04002853{
2854 if (get_modinfo(info, "livepatch")) {
2855 pr_err("%s: module is marked as livepatch module, but livepatch support is disabled",
2856 mod->name);
2857 return -ENOEXEC;
2858 }
2859
2860 return 0;
2861}
2862#endif /* CONFIG_LIVEPATCH */
2863
Andi Kleencaf75012018-01-25 15:50:28 -08002864static void check_modinfo_retpoline(struct module *mod, struct load_info *info)
2865{
2866 if (retpoline_module_ok(get_modinfo(info, "retpoline")))
2867 return;
2868
2869 pr_warn("%s: loading module not compiled with retpoline compiler.\n",
2870 mod->name);
2871}
2872
Kees Cook34e11692012-10-16 07:31:07 +10302873/* Sets info->hdr and info->len. */
2874static int copy_module_from_user(const void __user *umod, unsigned long len,
2875 struct load_info *info)
2876{
Kees Cook2e72d512012-10-16 07:32:07 +10302877 int err;
2878
Kees Cook34e11692012-10-16 07:31:07 +10302879 info->len = len;
2880 if (info->len < sizeof(*(info->hdr)))
Rusty Russell40dd2562010-08-05 12:59:03 -06002881 return -ENOEXEC;
2882
Mimi Zohara1db7422015-12-30 07:35:30 -05002883 err = security_kernel_read_file(NULL, READING_MODULE);
Kees Cook2e72d512012-10-16 07:32:07 +10302884 if (err)
2885 return err;
2886
Rusty Russell40dd2562010-08-05 12:59:03 -06002887 /* Suck in entire file: we'll want most of it. */
Kirill A. Shutemovcc9e6052015-03-24 12:31:40 +10302888 info->hdr = __vmalloc(info->len,
Michal Hocko19809c22017-05-08 15:57:44 -07002889 GFP_KERNEL | __GFP_NOWARN, PAGE_KERNEL);
Kees Cook34e11692012-10-16 07:31:07 +10302890 if (!info->hdr)
Rusty Russell40dd2562010-08-05 12:59:03 -06002891 return -ENOMEM;
2892
Linus Torvalds3afe9f82015-04-07 10:33:49 -07002893 if (copy_chunked_from_user(info->hdr, umod, info->len) != 0) {
Kees Cook34e11692012-10-16 07:31:07 +10302894 vfree(info->hdr);
2895 return -EFAULT;
Rusty Russell40dd2562010-08-05 12:59:03 -06002896 }
2897
Rusty Russell40dd2562010-08-05 12:59:03 -06002898 return 0;
Kees Cook34e11692012-10-16 07:31:07 +10302899}
Rusty Russell40dd2562010-08-05 12:59:03 -06002900
Rusty Russelld9131882010-08-05 12:59:08 -06002901static void free_copy(struct load_info *info)
2902{
Rusty Russelld9131882010-08-05 12:59:08 -06002903 vfree(info->hdr);
2904}
2905
Rusty Russell2f3238a2012-10-22 18:09:41 +10302906static int rewrite_section_headers(struct load_info *info, int flags)
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002907{
2908 unsigned int i;
2909
2910 /* This should always be true, but let's be sure. */
2911 info->sechdrs[0].sh_addr = 0;
2912
2913 for (i = 1; i < info->hdr->e_shnum; i++) {
2914 Elf_Shdr *shdr = &info->sechdrs[i];
2915 if (shdr->sh_type != SHT_NOBITS
2916 && info->len < shdr->sh_offset + shdr->sh_size) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08002917 pr_err("Module len %lu truncated\n", info->len);
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002918 return -ENOEXEC;
2919 }
2920
2921 /* Mark all sections sh_addr with their address in the
2922 temporary image. */
2923 shdr->sh_addr = (size_t)info->hdr + shdr->sh_offset;
2924
2925#ifndef CONFIG_MODULE_UNLOAD
2926 /* Don't load .exit sections */
2927 if (strstarts(info->secstrings+shdr->sh_name, ".exit"))
2928 shdr->sh_flags &= ~(unsigned long)SHF_ALLOC;
2929#endif
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002930 }
Rusty Russelld6df72a2010-08-05 12:59:07 -06002931
2932 /* Track but don't keep modinfo and version sections. */
Rusty Russelld6df72a2010-08-05 12:59:07 -06002933 info->sechdrs[info->index.vers].sh_flags &= ~(unsigned long)SHF_ALLOC;
Kees Cook3e2e8572017-04-21 15:35:27 -07002934 info->sechdrs[info->index.info].sh_flags &= ~(unsigned long)SHF_ALLOC;
2935
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002936 return 0;
2937}
2938
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002939/*
2940 * Set up our basic convenience variables (pointers to section headers,
2941 * search for module section index etc), and do some basic section
2942 * verification.
2943 *
Jessica Yu81a0abd2018-06-22 13:59:29 +02002944 * Set info->mod to the temporary copy of the module in info->hdr. The final one
2945 * will be allocated in move_module().
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002946 */
Jessica Yu81a0abd2018-06-22 13:59:29 +02002947static int setup_load_info(struct load_info *info, int flags)
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002948{
2949 unsigned int i;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002950
2951 /* Set up the convenience variables */
2952 info->sechdrs = (void *)info->hdr + info->hdr->e_shoff;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002953 info->secstrings = (void *)info->hdr
2954 + info->sechdrs[info->hdr->e_shstrndx].sh_offset;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002955
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002956 /* Try to find a name early so we can log errors with a module name */
2957 info->index.info = find_sec(info, ".modinfo");
2958 if (!info->index.info)
2959 info->name = "(missing .modinfo section)";
2960 else
2961 info->name = get_modinfo(info, "name");
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002962
2963 /* Find internal symbols and strings. */
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002964 for (i = 1; i < info->hdr->e_shnum; i++) {
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002965 if (info->sechdrs[i].sh_type == SHT_SYMTAB) {
2966 info->index.sym = i;
2967 info->index.str = info->sechdrs[i].sh_link;
Rusty Russell8b5f61a2010-08-05 12:59:06 -06002968 info->strtab = (char *)info->hdr
2969 + info->sechdrs[info->index.str].sh_offset;
2970 break;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002971 }
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002972 }
2973
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002974 if (info->index.sym == 0) {
2975 pr_warn("%s: module has no symbols (stripped?)\n", info->name);
2976 return -ENOEXEC;
2977 }
2978
Rusty Russell49668682010-08-05 12:59:10 -06002979 info->index.mod = find_sec(info, ".gnu.linkonce.this_module");
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002980 if (!info->index.mod) {
Kees Cook3e2e8572017-04-21 15:35:27 -07002981 pr_warn("%s: No module found in object\n",
2982 info->name ?: "(missing .modinfo name field)");
Jessica Yu81a0abd2018-06-22 13:59:29 +02002983 return -ENOEXEC;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002984 }
2985 /* This is temporary: point mod into copy of data. */
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002986 info->mod = (void *)info->hdr + info->sechdrs[info->index.mod].sh_offset;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002987
Kees Cook3e2e8572017-04-21 15:35:27 -07002988 /*
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002989 * If we didn't load the .modinfo 'name' field earlier, fall back to
Kees Cook3e2e8572017-04-21 15:35:27 -07002990 * on-disk struct mod 'name' field.
2991 */
2992 if (!info->name)
Jessica Yu81a0abd2018-06-22 13:59:29 +02002993 info->name = info->mod->name;
Kees Cook3e2e8572017-04-21 15:35:27 -07002994
Jessica Yu5fdc7db2018-06-22 14:00:01 +02002995 if (flags & MODULE_INIT_IGNORE_MODVERSIONS)
2996 info->index.vers = 0; /* Pretend no __versions section! */
2997 else
2998 info->index.vers = find_sec(info, "__versions");
Linus Torvalds3264d3f2010-06-02 11:01:06 -07002999
Rusty Russell49668682010-08-05 12:59:10 -06003000 info->index.pcpu = find_pcpusec(info);
Linus Torvalds3264d3f2010-06-02 11:01:06 -07003001
Jessica Yu81a0abd2018-06-22 13:59:29 +02003002 return 0;
Linus Torvalds3264d3f2010-06-02 11:01:06 -07003003}
3004
Rusty Russell2f3238a2012-10-22 18:09:41 +10303005static int check_modinfo(struct module *mod, struct load_info *info, int flags)
Rusty Russell40dd2562010-08-05 12:59:03 -06003006{
Rusty Russell49668682010-08-05 12:59:10 -06003007 const char *modmagic = get_modinfo(info, "vermagic");
Rusty Russell40dd2562010-08-05 12:59:03 -06003008 int err;
3009
Rusty Russell2f3238a2012-10-22 18:09:41 +10303010 if (flags & MODULE_INIT_IGNORE_VERMAGIC)
3011 modmagic = NULL;
3012
Rusty Russell40dd2562010-08-05 12:59:03 -06003013 /* This is allowed: modprobe --force will invalidate it. */
3014 if (!modmagic) {
3015 err = try_to_force_load(mod, "bad vermagic");
3016 if (err)
3017 return err;
Rusty Russell49668682010-08-05 12:59:10 -06003018 } else if (!same_magic(modmagic, vermagic, info->index.vers)) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003019 pr_err("%s: version magic '%s' should be '%s'\n",
Kees Cook3e2e8572017-04-21 15:35:27 -07003020 info->name, modmagic, vermagic);
Rusty Russell40dd2562010-08-05 12:59:03 -06003021 return -ENOEXEC;
3022 }
3023
Libor Pechacek3205c362016-04-13 11:06:12 +09303024 if (!get_modinfo(info, "intree")) {
3025 if (!test_taint(TAINT_OOT_MODULE))
3026 pr_warn("%s: loading out-of-tree module taints kernel.\n",
3027 mod->name);
Rusty Russell373d4d02013-01-21 17:17:39 +10303028 add_taint_module(mod, TAINT_OOT_MODULE, LOCKDEP_STILL_OK);
Libor Pechacek3205c362016-04-13 11:06:12 +09303029 }
Ben Hutchings2449b8b2011-10-24 15:12:28 +02003030
Andi Kleencaf75012018-01-25 15:50:28 -08003031 check_modinfo_retpoline(mod, info);
3032
Rusty Russell49668682010-08-05 12:59:10 -06003033 if (get_modinfo(info, "staging")) {
Rusty Russell373d4d02013-01-21 17:17:39 +10303034 add_taint_module(mod, TAINT_CRAP, LOCKDEP_STILL_OK);
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003035 pr_warn("%s: module is from the staging directory, the quality "
3036 "is unknown, you have been warned.\n", mod->name);
Rusty Russell40dd2562010-08-05 12:59:03 -06003037 }
Rusty Russell22e268e2010-08-05 12:59:05 -06003038
Josh Poimboeuf2992ef22016-08-25 10:04:45 -05003039 err = check_modinfo_livepatch(mod, info);
Jessica Yu1ce15ef2016-03-22 20:03:16 -04003040 if (err)
3041 return err;
3042
Rusty Russell22e268e2010-08-05 12:59:05 -06003043 /* Set up license info based on the info section */
Rusty Russell49668682010-08-05 12:59:10 -06003044 set_license(mod, get_modinfo(info, "license"));
Rusty Russell22e268e2010-08-05 12:59:05 -06003045
Rusty Russell40dd2562010-08-05 12:59:03 -06003046 return 0;
3047}
3048
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303049static int find_module_sections(struct module *mod, struct load_info *info)
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003050{
Rusty Russell49668682010-08-05 12:59:10 -06003051 mod->kp = section_objs(info, "__param",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003052 sizeof(*mod->kp), &mod->num_kp);
Rusty Russell49668682010-08-05 12:59:10 -06003053 mod->syms = section_objs(info, "__ksymtab",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003054 sizeof(*mod->syms), &mod->num_syms);
Rusty Russell49668682010-08-05 12:59:10 -06003055 mod->crcs = section_addr(info, "__kcrctab");
3056 mod->gpl_syms = section_objs(info, "__ksymtab_gpl",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003057 sizeof(*mod->gpl_syms),
3058 &mod->num_gpl_syms);
Rusty Russell49668682010-08-05 12:59:10 -06003059 mod->gpl_crcs = section_addr(info, "__kcrctab_gpl");
3060 mod->gpl_future_syms = section_objs(info,
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003061 "__ksymtab_gpl_future",
3062 sizeof(*mod->gpl_future_syms),
3063 &mod->num_gpl_future_syms);
Rusty Russell49668682010-08-05 12:59:10 -06003064 mod->gpl_future_crcs = section_addr(info, "__kcrctab_gpl_future");
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003065
3066#ifdef CONFIG_UNUSED_SYMBOLS
Rusty Russell49668682010-08-05 12:59:10 -06003067 mod->unused_syms = section_objs(info, "__ksymtab_unused",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003068 sizeof(*mod->unused_syms),
3069 &mod->num_unused_syms);
Rusty Russell49668682010-08-05 12:59:10 -06003070 mod->unused_crcs = section_addr(info, "__kcrctab_unused");
3071 mod->unused_gpl_syms = section_objs(info, "__ksymtab_unused_gpl",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003072 sizeof(*mod->unused_gpl_syms),
3073 &mod->num_unused_gpl_syms);
Rusty Russell49668682010-08-05 12:59:10 -06003074 mod->unused_gpl_crcs = section_addr(info, "__kcrctab_unused_gpl");
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003075#endif
3076#ifdef CONFIG_CONSTRUCTORS
Rusty Russell49668682010-08-05 12:59:10 -06003077 mod->ctors = section_objs(info, ".ctors",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003078 sizeof(*mod->ctors), &mod->num_ctors);
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303079 if (!mod->ctors)
3080 mod->ctors = section_objs(info, ".init_array",
3081 sizeof(*mod->ctors), &mod->num_ctors);
3082 else if (find_sec(info, ".init_array")) {
3083 /*
3084 * This shouldn't happen with same compiler and binutils
3085 * building all parts of the module.
3086 */
Ionut Alexa6da0b562014-11-10 09:31:29 +10303087 pr_warn("%s: has both .ctors and .init_array.\n",
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303088 mod->name);
3089 return -EINVAL;
3090 }
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003091#endif
3092
3093#ifdef CONFIG_TRACEPOINTS
Mathieu Desnoyers65498642011-01-26 17:26:22 -05003094 mod->tracepoints_ptrs = section_objs(info, "__tracepoints_ptrs",
3095 sizeof(*mod->tracepoints_ptrs),
3096 &mod->num_tracepoints);
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003097#endif
Jason Baronbf5438fc2010-09-17 11:09:00 -04003098#ifdef HAVE_JUMP_LABEL
3099 mod->jump_entries = section_objs(info, "__jump_table",
3100 sizeof(*mod->jump_entries),
3101 &mod->num_jump_entries);
3102#endif
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003103#ifdef CONFIG_EVENT_TRACING
Rusty Russell49668682010-08-05 12:59:10 -06003104 mod->trace_events = section_objs(info, "_ftrace_events",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003105 sizeof(*mod->trace_events),
3106 &mod->num_trace_events);
Jeremy Linton99be6472017-05-31 16:56:44 -05003107 mod->trace_evals = section_objs(info, "_ftrace_eval_map",
3108 sizeof(*mod->trace_evals),
3109 &mod->num_trace_evals);
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003110#endif
Steven Rostedt13b9b6e2010-11-10 22:19:24 -05003111#ifdef CONFIG_TRACING
3112 mod->trace_bprintk_fmt_start = section_objs(info, "__trace_printk_fmt",
3113 sizeof(*mod->trace_bprintk_fmt_start),
3114 &mod->num_trace_bprintk_fmt);
Steven Rostedt13b9b6e2010-11-10 22:19:24 -05003115#endif
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003116#ifdef CONFIG_FTRACE_MCOUNT_RECORD
3117 /* sechdrs[0].sh_size is always zero */
Rusty Russell49668682010-08-05 12:59:10 -06003118 mod->ftrace_callsites = section_objs(info, "__mcount_loc",
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003119 sizeof(*mod->ftrace_callsites),
3120 &mod->num_ftrace_callsites);
3121#endif
Masami Hiramatsu540adea2018-01-13 02:55:03 +09003122#ifdef CONFIG_FUNCTION_ERROR_INJECTION
3123 mod->ei_funcs = section_objs(info, "_error_injection_whitelist",
3124 sizeof(*mod->ei_funcs),
3125 &mod->num_ei_funcs);
Josef Bacik92ace992017-12-11 11:36:46 -05003126#endif
Rusty Russell811d66a2010-08-05 12:59:12 -06003127 mod->extable = section_objs(info, "__ex_table",
3128 sizeof(*mod->extable), &mod->num_exentries);
3129
Rusty Russell49668682010-08-05 12:59:10 -06003130 if (section_addr(info, "__obsparm"))
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003131 pr_warn("%s: Ignoring obsolete parameters\n", mod->name);
Rusty Russell811d66a2010-08-05 12:59:12 -06003132
3133 info->debug = section_objs(info, "__verbose",
3134 sizeof(*info->debug), &info->num_debug);
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303135
3136 return 0;
Linus Torvaldsf91a13b2010-08-05 12:59:02 -06003137}
3138
Rusty Russell49668682010-08-05 12:59:10 -06003139static int move_module(struct module *mod, struct load_info *info)
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003140{
3141 int i;
3142 void *ptr;
3143
3144 /* Do the allocs. */
Rusty Russell7523e4d2015-11-26 09:44:08 +10303145 ptr = module_alloc(mod->core_layout.size);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003146 /*
3147 * The pointer to this block is stored in the module structure
3148 * which is inside the block. Just mark it as not being a
3149 * leak.
3150 */
3151 kmemleak_not_leak(ptr);
3152 if (!ptr)
Rusty Russelld9131882010-08-05 12:59:08 -06003153 return -ENOMEM;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003154
Rusty Russell7523e4d2015-11-26 09:44:08 +10303155 memset(ptr, 0, mod->core_layout.size);
3156 mod->core_layout.base = ptr;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003157
Rusty Russell7523e4d2015-11-26 09:44:08 +10303158 if (mod->init_layout.size) {
3159 ptr = module_alloc(mod->init_layout.size);
Rusty Russell82fab442012-12-11 09:38:33 +10303160 /*
3161 * The pointer to this block is stored in the module structure
3162 * which is inside the block. This block doesn't need to be
3163 * scanned as it contains data and code that will be freed
3164 * after the module is initialized.
3165 */
3166 kmemleak_ignore(ptr);
3167 if (!ptr) {
Rusty Russell7523e4d2015-11-26 09:44:08 +10303168 module_memfree(mod->core_layout.base);
Rusty Russell82fab442012-12-11 09:38:33 +10303169 return -ENOMEM;
3170 }
Rusty Russell7523e4d2015-11-26 09:44:08 +10303171 memset(ptr, 0, mod->init_layout.size);
3172 mod->init_layout.base = ptr;
Rusty Russell82fab442012-12-11 09:38:33 +10303173 } else
Rusty Russell7523e4d2015-11-26 09:44:08 +10303174 mod->init_layout.base = NULL;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003175
3176 /* Transfer each section which specifies SHF_ALLOC */
Jim Cromie5e124162011-12-06 12:11:31 -07003177 pr_debug("final section addresses:\n");
Rusty Russell49668682010-08-05 12:59:10 -06003178 for (i = 0; i < info->hdr->e_shnum; i++) {
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003179 void *dest;
Rusty Russell49668682010-08-05 12:59:10 -06003180 Elf_Shdr *shdr = &info->sechdrs[i];
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003181
Rusty Russell49668682010-08-05 12:59:10 -06003182 if (!(shdr->sh_flags & SHF_ALLOC))
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003183 continue;
3184
Rusty Russell49668682010-08-05 12:59:10 -06003185 if (shdr->sh_entsize & INIT_OFFSET_MASK)
Rusty Russell7523e4d2015-11-26 09:44:08 +10303186 dest = mod->init_layout.base
Rusty Russell49668682010-08-05 12:59:10 -06003187 + (shdr->sh_entsize & ~INIT_OFFSET_MASK);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003188 else
Rusty Russell7523e4d2015-11-26 09:44:08 +10303189 dest = mod->core_layout.base + shdr->sh_entsize;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003190
Rusty Russell49668682010-08-05 12:59:10 -06003191 if (shdr->sh_type != SHT_NOBITS)
3192 memcpy(dest, (void *)shdr->sh_addr, shdr->sh_size);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003193 /* Update sh_addr to point to copy in image. */
Rusty Russell49668682010-08-05 12:59:10 -06003194 shdr->sh_addr = (unsigned long)dest;
Jim Cromie5e124162011-12-06 12:11:31 -07003195 pr_debug("\t0x%lx %s\n",
3196 (long)shdr->sh_addr, info->secstrings + shdr->sh_name);
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003197 }
Rusty Russelld9131882010-08-05 12:59:08 -06003198
3199 return 0;
Linus Torvalds65b8a9b2010-08-05 12:59:02 -06003200}
3201
Rusty Russell49668682010-08-05 12:59:10 -06003202static int check_module_license_and_versions(struct module *mod)
Rusty Russell22e268e2010-08-05 12:59:05 -06003203{
Libor Pechacek3205c362016-04-13 11:06:12 +09303204 int prev_taint = test_taint(TAINT_PROPRIETARY_MODULE);
3205
Rusty Russell22e268e2010-08-05 12:59:05 -06003206 /*
3207 * ndiswrapper is under GPL by itself, but loads proprietary modules.
3208 * Don't use add_taint_module(), as it would prevent ndiswrapper from
3209 * using GPL-only symbols it needs.
3210 */
3211 if (strcmp(mod->name, "ndiswrapper") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303212 add_taint(TAINT_PROPRIETARY_MODULE, LOCKDEP_NOW_UNRELIABLE);
Rusty Russell22e268e2010-08-05 12:59:05 -06003213
3214 /* driverloader was caught wrongly pretending to be under GPL */
3215 if (strcmp(mod->name, "driverloader") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303216 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3217 LOCKDEP_NOW_UNRELIABLE);
Rusty Russell22e268e2010-08-05 12:59:05 -06003218
Matthew Garrettc99af372012-06-22 13:49:31 -04003219 /* lve claims to be GPL but upstream won't provide source */
3220 if (strcmp(mod->name, "lve") == 0)
Rusty Russell373d4d02013-01-21 17:17:39 +10303221 add_taint_module(mod, TAINT_PROPRIETARY_MODULE,
3222 LOCKDEP_NOW_UNRELIABLE);
Matthew Garrettc99af372012-06-22 13:49:31 -04003223
Libor Pechacek3205c362016-04-13 11:06:12 +09303224 if (!prev_taint && test_taint(TAINT_PROPRIETARY_MODULE))
3225 pr_warn("%s: module license taints kernel.\n", mod->name);
3226
Rusty Russell22e268e2010-08-05 12:59:05 -06003227#ifdef CONFIG_MODVERSIONS
3228 if ((mod->num_syms && !mod->crcs)
3229 || (mod->num_gpl_syms && !mod->gpl_crcs)
3230 || (mod->num_gpl_future_syms && !mod->gpl_future_crcs)
3231#ifdef CONFIG_UNUSED_SYMBOLS
3232 || (mod->num_unused_syms && !mod->unused_crcs)
3233 || (mod->num_unused_gpl_syms && !mod->unused_gpl_crcs)
3234#endif
3235 ) {
3236 return try_to_force_load(mod,
3237 "no versions for exported symbols");
3238 }
3239#endif
3240 return 0;
3241}
3242
3243static void flush_module_icache(const struct module *mod)
3244{
3245 mm_segment_t old_fs;
3246
3247 /* flush the icache in correct context */
3248 old_fs = get_fs();
3249 set_fs(KERNEL_DS);
3250
3251 /*
3252 * Flush the instruction cache, since we've played with text.
3253 * Do it before processing of module parameters, so the module
3254 * can provide parameter accessor functions of its own.
3255 */
Rusty Russell7523e4d2015-11-26 09:44:08 +10303256 if (mod->init_layout.base)
3257 flush_icache_range((unsigned long)mod->init_layout.base,
3258 (unsigned long)mod->init_layout.base
3259 + mod->init_layout.size);
3260 flush_icache_range((unsigned long)mod->core_layout.base,
3261 (unsigned long)mod->core_layout.base + mod->core_layout.size);
Rusty Russell22e268e2010-08-05 12:59:05 -06003262
3263 set_fs(old_fs);
3264}
3265
Jonas Bonn74e08fc2011-06-30 21:22:11 +02003266int __weak module_frob_arch_sections(Elf_Ehdr *hdr,
3267 Elf_Shdr *sechdrs,
3268 char *secstrings,
3269 struct module *mod)
3270{
3271 return 0;
3272}
3273
Prarit Bhargavabe7de5f2016-07-21 15:37:56 +09303274/* module_blacklist is a comma-separated list of module names */
3275static char *module_blacklist;
Luis R. Rodriguez96b5b192017-06-28 18:32:31 -07003276static bool blacklisted(const char *module_name)
Prarit Bhargavabe7de5f2016-07-21 15:37:56 +09303277{
3278 const char *p;
3279 size_t len;
3280
3281 if (!module_blacklist)
3282 return false;
3283
3284 for (p = module_blacklist; *p; p += len) {
3285 len = strcspn(p, ",");
3286 if (strlen(module_name) == len && !memcmp(module_name, p, len))
3287 return true;
3288 if (p[len] == ',')
3289 len++;
3290 }
3291 return false;
3292}
3293core_param(module_blacklist, module_blacklist, charp, 0400);
3294
Rusty Russell2f3238a2012-10-22 18:09:41 +10303295static struct module *layout_and_allocate(struct load_info *info, int flags)
Rusty Russelld9131882010-08-05 12:59:08 -06003296{
Rusty Russelld9131882010-08-05 12:59:08 -06003297 struct module *mod;
Jessica Yu444d13f2016-07-27 12:06:21 +09303298 unsigned int ndx;
Rusty Russelld9131882010-08-05 12:59:08 -06003299 int err;
3300
Jessica Yu81a0abd2018-06-22 13:59:29 +02003301 err = check_modinfo(info->mod, info, flags);
Rusty Russelld9131882010-08-05 12:59:08 -06003302 if (err)
3303 return ERR_PTR(err);
3304
3305 /* Allow arches to frob section contents and sizes. */
Rusty Russell49668682010-08-05 12:59:10 -06003306 err = module_frob_arch_sections(info->hdr, info->sechdrs,
Jessica Yu81a0abd2018-06-22 13:59:29 +02003307 info->secstrings, info->mod);
Rusty Russelld9131882010-08-05 12:59:08 -06003308 if (err < 0)
Rusty Russell8d8022e2013-07-03 10:06:28 +09303309 return ERR_PTR(err);
Rusty Russelld9131882010-08-05 12:59:08 -06003310
Rusty Russell8d8022e2013-07-03 10:06:28 +09303311 /* We will do a special allocation for per-cpu sections later. */
3312 info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
Rusty Russelld9131882010-08-05 12:59:08 -06003313
Jessica Yu444d13f2016-07-27 12:06:21 +09303314 /*
3315 * Mark ro_after_init section with SHF_RO_AFTER_INIT so that
3316 * layout_sections() can put it in the right place.
3317 * Note: ro_after_init sections also have SHF_{WRITE,ALLOC} set.
3318 */
3319 ndx = find_sec(info, ".data..ro_after_init");
3320 if (ndx)
3321 info->sechdrs[ndx].sh_flags |= SHF_RO_AFTER_INIT;
3322
Rusty Russelld9131882010-08-05 12:59:08 -06003323 /* Determine total sizes, and put offsets in sh_entsize. For now
3324 this is done generically; there doesn't appear to be any
3325 special cases for the architectures. */
Jessica Yu81a0abd2018-06-22 13:59:29 +02003326 layout_sections(info->mod, info);
3327 layout_symtab(info->mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003328
3329 /* Allocate and move to the final place */
Jessica Yu81a0abd2018-06-22 13:59:29 +02003330 err = move_module(info->mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003331 if (err)
Rusty Russell8d8022e2013-07-03 10:06:28 +09303332 return ERR_PTR(err);
Rusty Russelld9131882010-08-05 12:59:08 -06003333
3334 /* Module has been copied to its final place now: return it. */
3335 mod = (void *)info->sechdrs[info->index.mod].sh_addr;
Rusty Russell49668682010-08-05 12:59:10 -06003336 kmemleak_load_module(mod, info);
Rusty Russelld9131882010-08-05 12:59:08 -06003337 return mod;
Rusty Russelld9131882010-08-05 12:59:08 -06003338}
3339
3340/* mod is no longer valid after this! */
3341static void module_deallocate(struct module *mod, struct load_info *info)
3342{
Rusty Russelld9131882010-08-05 12:59:08 -06003343 percpu_modfree(mod);
Rusty Russelld453cde2015-01-20 09:07:04 +10303344 module_arch_freeing_init(mod);
Rusty Russell7523e4d2015-11-26 09:44:08 +10303345 module_memfree(mod->init_layout.base);
3346 module_memfree(mod->core_layout.base);
Rusty Russelld9131882010-08-05 12:59:08 -06003347}
3348
Jonas Bonn74e08fc2011-06-30 21:22:11 +02003349int __weak module_finalize(const Elf_Ehdr *hdr,
3350 const Elf_Shdr *sechdrs,
3351 struct module *me)
3352{
3353 return 0;
3354}
3355
Rusty Russell811d66a2010-08-05 12:59:12 -06003356static int post_relocation(struct module *mod, const struct load_info *info)
3357{
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003358 /* Sort exception table now relocations are done. */
Rusty Russell811d66a2010-08-05 12:59:12 -06003359 sort_extable(mod->extable, mod->extable + mod->num_exentries);
3360
3361 /* Copy relocated percpu area over. */
3362 percpu_modcopy(mod, (void *)info->sechdrs[info->index.pcpu].sh_addr,
3363 info->sechdrs[info->index.pcpu].sh_size);
3364
Rusty Russell51f3d0f2010-08-05 12:59:13 -06003365 /* Setup kallsyms-specific fields. */
Rusty Russell811d66a2010-08-05 12:59:12 -06003366 add_kallsyms(mod, info);
3367
3368 /* Arch-specific module finalizing. */
3369 return module_finalize(info->hdr, info->sechdrs, mod);
3370}
3371
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303372/* Is this module of this name done loading? No locks held. */
3373static bool finished_loading(const char *name)
3374{
3375 struct module *mod;
3376 bool ret;
3377
Peter Zijlstra9cc019b2015-02-11 15:01:13 +10303378 /*
3379 * The module_mutex should not be a heavily contended lock;
3380 * if we get the occasional sleep here, we'll go an extra iteration
3381 * in the wait_event_interruptible(), which is harmless.
3382 */
3383 sched_annotate_sleep();
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303384 mutex_lock(&module_mutex);
Mathias Krause4f6de4d52013-07-02 15:35:11 +09303385 mod = find_module_all(name, strlen(name), true);
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303386 ret = !mod || mod->state == MODULE_STATE_LIVE
3387 || mod->state == MODULE_STATE_GOING;
Rusty Russell9bb9c3b2012-09-28 14:31:03 +09303388 mutex_unlock(&module_mutex);
3389
3390 return ret;
3391}
3392
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07003393/* Call module constructors. */
3394static void do_mod_ctors(struct module *mod)
3395{
3396#ifdef CONFIG_CONSTRUCTORS
3397 unsigned long i;
3398
3399 for (i = 0; i < mod->num_ctors; i++)
3400 mod->ctors[i]();
3401#endif
3402}
3403
Rusty Russellc7496372015-01-20 09:07:05 +10303404/* For freeing module_init on success, in case kallsyms traversing */
3405struct mod_initfree {
3406 struct rcu_head rcu;
3407 void *module_init;
3408};
3409
3410static void do_free_init(struct rcu_head *head)
3411{
3412 struct mod_initfree *m = container_of(head, struct mod_initfree, rcu);
3413 module_memfree(m->module_init);
3414 kfree(m);
3415}
3416
Jan Kiszkabe02a182015-02-17 13:46:50 -08003417/*
3418 * This is where the real work happens.
3419 *
3420 * Keep it uninlined to provide a reliable breakpoint target, e.g. for the gdb
3421 * helper command 'lx-symbols'.
3422 */
3423static noinline int do_init_module(struct module *mod)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003424{
Linus Torvalds1da177e2005-04-16 15:20:36 -07003425 int ret = 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303426 struct mod_initfree *freeinit;
3427
3428 freeinit = kmalloc(sizeof(*freeinit), GFP_KERNEL);
3429 if (!freeinit) {
3430 ret = -ENOMEM;
3431 goto fail;
3432 }
Rusty Russell7523e4d2015-11-26 09:44:08 +10303433 freeinit->module_init = mod->init_layout.base;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003434
Tejun Heo774a1222013-01-15 18:52:51 -08003435 /*
3436 * We want to find out whether @mod uses async during init. Clear
3437 * PF_USED_ASYNC. async_schedule*() will set it.
3438 */
3439 current->flags &= ~PF_USED_ASYNC;
3440
Peter Oberparleiterb99b87f2009-06-17 16:28:03 -07003441 do_mod_ctors(mod);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003442 /* Start the module */
3443 if (mod->init != NULL)
Arjan van de Ven59f94152008-07-30 12:49:02 -07003444 ret = do_one_initcall(mod->init);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003445 if (ret < 0) {
Rusty Russellc7496372015-01-20 09:07:05 +10303446 goto fail_free_freeinit;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003447 }
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07003448 if (ret > 0) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003449 pr_warn("%s: '%s'->init suspiciously returned %d, it should "
3450 "follow 0/-E convention\n"
3451 "%s: loading module anyway...\n",
3452 __func__, mod->name, ret, __func__);
Alexey Dobriyane24e2e62008-03-10 11:43:53 -07003453 dump_stack();
3454 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07003455
Rusty Russell6f139092012-09-28 14:31:03 +09303456 /* Now it's a first class citizen! */
Linus Torvalds1da177e2005-04-16 15:20:36 -07003457 mod->state = MODULE_STATE_LIVE;
Masami Hiramatsu0deddf42009-01-06 14:41:54 -08003458 blocking_notifier_call_chain(&module_notify_list,
3459 MODULE_STATE_LIVE, mod);
Rusty Russell6c5db222008-03-10 11:43:52 -07003460
Tejun Heo774a1222013-01-15 18:52:51 -08003461 /*
3462 * We need to finish all async code before the module init sequence
3463 * is done. This has potential to deadlock. For example, a newly
3464 * detected block device can trigger request_module() of the
3465 * default iosched from async probing task. Once userland helper
3466 * reaches here, async_synchronize_full() will wait on the async
3467 * task waiting on request_module() and deadlock.
3468 *
3469 * This deadlock is avoided by perfomring async_synchronize_full()
3470 * iff module init queued any async jobs. This isn't a full
3471 * solution as it will deadlock the same if module loading from
3472 * async jobs nests more than once; however, due to the various
3473 * constraints, this hack seems to be the best option for now.
3474 * Please refer to the following thread for details.
3475 *
3476 * http://thread.gmane.org/gmane.linux.kernel/1420814
3477 */
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003478 if (!mod->async_probe_requested && (current->flags & PF_USED_ASYNC))
Tejun Heo774a1222013-01-15 18:52:51 -08003479 async_synchronize_full();
Linus Torvaldsd6de2c82009-04-10 12:17:41 -07003480
Steven Rostedt (VMware)aba4b5c2017-09-01 08:35:38 -04003481 ftrace_free_mem(mod, mod->init_layout.base, mod->init_layout.base +
Steven Rostedt (VMware)3e234282017-03-03 18:00:22 -05003482 mod->init_layout.size);
Rusty Russell6c5db222008-03-10 11:43:52 -07003483 mutex_lock(&module_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003484 /* Drop initial reference. */
3485 module_put(mod);
Rusty Russellad6561d2009-06-12 21:47:03 -06003486 trim_init_extable(mod);
Jan Beulich4a496222009-07-06 14:50:42 +01003487#ifdef CONFIG_KALLSYMS
Rusty Russell82440622016-02-03 16:55:26 +10303488 /* Switch to core kallsyms now init is done: kallsyms may be walking! */
3489 rcu_assign_pointer(mod->kallsyms, &mod->core_kallsyms);
Jan Beulich4a496222009-07-06 14:50:42 +01003490#endif
Jessica Yu444d13f2016-07-27 12:06:21 +09303491 module_enable_ro(mod, true);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09303492 mod_tree_remove_init(mod);
Rusty Russell85c898d2015-11-26 09:45:08 +10303493 disable_ro_nx(&mod->init_layout);
Rusty Russelld453cde2015-01-20 09:07:04 +10303494 module_arch_freeing_init(mod);
Rusty Russell7523e4d2015-11-26 09:44:08 +10303495 mod->init_layout.base = NULL;
3496 mod->init_layout.size = 0;
3497 mod->init_layout.ro_size = 0;
Jessica Yu444d13f2016-07-27 12:06:21 +09303498 mod->init_layout.ro_after_init_size = 0;
Rusty Russell7523e4d2015-11-26 09:44:08 +10303499 mod->init_layout.text_size = 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303500 /*
3501 * We want to free module_init, but be aware that kallsyms may be
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303502 * walking this with preempt disabled. In all the failure paths, we
3503 * call synchronize_sched(), but we don't want to slow down the success
3504 * path, so use actual RCU here.
Jeffrey Hugoae646f02018-05-11 16:01:42 -07003505 * Note that module_alloc() on most architectures creates W+X page
3506 * mappings which won't be cleaned up until do_free_init() runs. Any
3507 * code such as mark_rodata_ro() which depends on those mappings to
3508 * be cleaned up needs to sync with the queued work - ie
3509 * rcu_barrier_sched()
Rusty Russellc7496372015-01-20 09:07:05 +10303510 */
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303511 call_rcu_sched(&freeinit->rcu, do_free_init);
Ashutosh Naik6389a382006-03-23 03:00:46 -08003512 mutex_unlock(&module_mutex);
Rusty Russell6f139092012-09-28 14:31:03 +09303513 wake_up_all(&module_wq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003514
3515 return 0;
Rusty Russellc7496372015-01-20 09:07:05 +10303516
3517fail_free_freeinit:
3518 kfree(freeinit);
3519fail:
3520 /* Try to protect us from buggy refcounters. */
3521 mod->state = MODULE_STATE_GOING;
3522 synchronize_sched();
3523 module_put(mod);
3524 blocking_notifier_call_chain(&module_notify_list,
3525 MODULE_STATE_GOING, mod);
Jessica Yu7e545d62016-03-16 20:55:39 -04003526 klp_module_going(mod);
Jessica Yu7dcd1822016-02-16 17:32:33 -05003527 ftrace_release_mod(mod);
Rusty Russellc7496372015-01-20 09:07:05 +10303528 free_module(mod);
3529 wake_up_all(&module_wq);
3530 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003531}
3532
Kees Cook34e11692012-10-16 07:31:07 +10303533static int may_init_module(void)
3534{
3535 if (!capable(CAP_SYS_MODULE) || modules_disabled)
3536 return -EPERM;
3537
3538 return 0;
3539}
3540
Rusty Russella3535c72013-01-21 17:18:59 +10303541/*
3542 * We try to place it in the list now to make sure it's unique before
3543 * we dedicate too many resources. In particular, temporary percpu
3544 * memory exhaustion.
3545 */
3546static int add_unformed_module(struct module *mod)
3547{
3548 int err;
3549 struct module *old;
3550
3551 mod->state = MODULE_STATE_UNFORMED;
3552
3553again:
3554 mutex_lock(&module_mutex);
Mathias Krause4f6de4d52013-07-02 15:35:11 +09303555 old = find_module_all(mod->name, strlen(mod->name), true);
3556 if (old != NULL) {
Rusty Russella3535c72013-01-21 17:18:59 +10303557 if (old->state == MODULE_STATE_COMING
3558 || old->state == MODULE_STATE_UNFORMED) {
3559 /* Wait in case it fails to load. */
3560 mutex_unlock(&module_mutex);
Peter Zijlstra9cc019b2015-02-11 15:01:13 +10303561 err = wait_event_interruptible(module_wq,
3562 finished_loading(mod->name));
Rusty Russella3535c72013-01-21 17:18:59 +10303563 if (err)
3564 goto out_unlocked;
3565 goto again;
3566 }
3567 err = -EEXIST;
3568 goto out;
3569 }
Peter Zijlstra4f6665462015-05-27 11:09:38 +09303570 mod_update_bounds(mod);
Rusty Russella3535c72013-01-21 17:18:59 +10303571 list_add_rcu(&mod->list, &modules);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09303572 mod_tree_insert(mod);
Rusty Russella3535c72013-01-21 17:18:59 +10303573 err = 0;
3574
3575out:
3576 mutex_unlock(&module_mutex);
3577out_unlocked:
3578 return err;
3579}
3580
3581static int complete_formation(struct module *mod, struct load_info *info)
3582{
3583 int err;
3584
3585 mutex_lock(&module_mutex);
3586
3587 /* Find duplicate symbols (must be called under lock). */
3588 err = verify_export_symbols(mod);
3589 if (err < 0)
3590 goto out;
3591
3592 /* This relies on module_mutex for list integrity. */
3593 module_bug_finalize(info->hdr, info->sechdrs, mod);
3594
Jessica Yu444d13f2016-07-27 12:06:21 +09303595 module_enable_ro(mod, false);
Rusty Russell85c898d2015-11-26 09:45:08 +10303596 module_enable_nx(mod);
Rusty Russell49822232014-05-14 10:54:19 +09303597
Rusty Russella3535c72013-01-21 17:18:59 +10303598 /* Mark state as coming so strong_try_module_get() ignores us,
3599 * but kallsyms etc. can see us. */
3600 mod->state = MODULE_STATE_COMING;
Rusty Russell49822232014-05-14 10:54:19 +09303601 mutex_unlock(&module_mutex);
3602
Rusty Russell49822232014-05-14 10:54:19 +09303603 return 0;
Rusty Russella3535c72013-01-21 17:18:59 +10303604
3605out:
3606 mutex_unlock(&module_mutex);
3607 return err;
3608}
3609
Jessica Yu4c973d12016-03-16 20:55:38 -04003610static int prepare_coming_module(struct module *mod)
3611{
Jessica Yu7e545d62016-03-16 20:55:39 -04003612 int err;
3613
Jessica Yu4c973d12016-03-16 20:55:38 -04003614 ftrace_module_enable(mod);
Jessica Yu7e545d62016-03-16 20:55:39 -04003615 err = klp_module_coming(mod);
3616 if (err)
3617 return err;
3618
Jessica Yu4c973d12016-03-16 20:55:38 -04003619 blocking_notifier_call_chain(&module_notify_list,
3620 MODULE_STATE_COMING, mod);
3621 return 0;
3622}
3623
Luis R. Rodriguezecc86172015-03-30 16:20:03 -07003624static int unknown_module_param_cb(char *param, char *val, const char *modname,
3625 void *arg)
Rusty Russell54041d82013-07-02 15:35:12 +09303626{
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003627 struct module *mod = arg;
3628 int ret;
3629
3630 if (strcmp(param, "async_probe") == 0) {
3631 mod->async_probe_requested = true;
3632 return 0;
3633 }
3634
Ionut Alexa6da0b562014-11-10 09:31:29 +10303635 /* Check for magic 'dyndbg' arg */
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -07003636 ret = ddebug_dyndbg_module_param_cb(param, val, modname);
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003637 if (ret != 0)
3638 pr_warn("%s: unknown parameter '%s' ignored\n", modname, param);
Rusty Russell54041d82013-07-02 15:35:12 +09303639 return 0;
3640}
3641
Kees Cook34e11692012-10-16 07:31:07 +10303642/* Allocate and load the module: note that size of section 0 is always
3643 zero, and we rely on this for optional sections. */
Rusty Russell2f3238a2012-10-22 18:09:41 +10303644static int load_module(struct load_info *info, const char __user *uargs,
3645 int flags)
Kees Cook34e11692012-10-16 07:31:07 +10303646{
Rusty Russella3535c72013-01-21 17:18:59 +10303647 struct module *mod;
Jessica Yu5fdc7db2018-06-22 14:00:01 +02003648 long err = 0;
Rusty Russell51e158c2014-04-28 11:34:33 +09303649 char *after_dashes;
Kees Cook34e11692012-10-16 07:31:07 +10303650
Jessica Yu5fdc7db2018-06-22 14:00:01 +02003651 err = elf_header_check(info);
3652 if (err)
3653 goto free_copy;
3654
3655 err = setup_load_info(info, flags);
3656 if (err)
3657 goto free_copy;
3658
3659 if (blacklisted(info->name)) {
3660 err = -EPERM;
3661 goto free_copy;
3662 }
3663
Ben Hutchingsbca014c2016-04-28 09:24:01 +09303664 err = module_sig_check(info, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303665 if (err)
3666 goto free_copy;
3667
Jessica Yu5fdc7db2018-06-22 14:00:01 +02003668 err = rewrite_section_headers(info, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303669 if (err)
3670 goto free_copy;
3671
Jessica Yu5fdc7db2018-06-22 14:00:01 +02003672 /* Check module struct version now, before we try to use module. */
3673 if (!check_modstruct_version(info, info->mod)) {
3674 err = -ENOEXEC;
3675 goto free_copy;
3676 }
3677
Kees Cook34e11692012-10-16 07:31:07 +10303678 /* Figure out module layout, and allocate all the memory. */
Rusty Russell2f3238a2012-10-22 18:09:41 +10303679 mod = layout_and_allocate(info, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303680 if (IS_ERR(mod)) {
3681 err = PTR_ERR(mod);
3682 goto free_copy;
3683 }
3684
Richard Guy Briggsca86cad2017-02-04 13:10:38 -05003685 audit_log_kern_module(mod->name);
3686
Rusty Russella3535c72013-01-21 17:18:59 +10303687 /* Reserve our place in the list. */
3688 err = add_unformed_module(mod);
3689 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303690 goto free_module;
Rusty Russell1fb93412013-01-12 13:27:34 +10303691
Kees Cook34e11692012-10-16 07:31:07 +10303692#ifdef CONFIG_MODULE_SIG
3693 mod->sig_ok = info->sig_ok;
Rusty Russell64748a22013-01-21 17:03:02 +10303694 if (!mod->sig_ok) {
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003695 pr_notice_once("%s: module verification failed: signature "
Marcel Holtmannab92ebb2015-02-06 15:09:57 +10303696 "and/or required key missing - tainting "
Andrew Mortonbddb12b2013-11-12 15:11:28 -08003697 "kernel\n", mod->name);
Mathieu Desnoyers66cc69e2014-03-13 12:11:30 +10303698 add_taint_module(mod, TAINT_UNSIGNED_MODULE, LOCKDEP_STILL_OK);
Rusty Russell64748a22013-01-21 17:03:02 +10303699 }
Kees Cook34e11692012-10-16 07:31:07 +10303700#endif
3701
Rusty Russell8d8022e2013-07-03 10:06:28 +09303702 /* To avoid stressing percpu allocator, do this once we're unique. */
Rusty Russell9eb76d72013-07-03 10:06:29 +09303703 err = percpu_modalloc(mod, info);
Rusty Russell8d8022e2013-07-03 10:06:28 +09303704 if (err)
3705 goto unlink_mod;
3706
Kees Cook34e11692012-10-16 07:31:07 +10303707 /* Now module is in final location, initialize linked lists, etc. */
3708 err = module_unload_init(mod);
3709 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303710 goto unlink_mod;
Kees Cook34e11692012-10-16 07:31:07 +10303711
Rusty Russellcf2fde72015-06-26 06:44:38 +09303712 init_param_lock(mod);
Dan Streetmanb51d23e2015-06-17 06:18:52 +09303713
Kees Cook34e11692012-10-16 07:31:07 +10303714 /* Now we've got everything in the final locations, we can
3715 * find optional sections. */
Frantisek Hrbataeb3057d2013-10-14 18:08:46 +10303716 err = find_module_sections(mod, info);
3717 if (err)
3718 goto free_unload;
Kees Cook34e11692012-10-16 07:31:07 +10303719
3720 err = check_module_license_and_versions(mod);
3721 if (err)
3722 goto free_unload;
3723
3724 /* Set up MODINFO_ATTR fields */
3725 setup_modinfo(mod, info);
3726
3727 /* Fix up syms, so that st_value is a pointer to location. */
3728 err = simplify_symbols(mod, info);
3729 if (err < 0)
3730 goto free_modinfo;
3731
3732 err = apply_relocations(mod, info);
3733 if (err < 0)
3734 goto free_modinfo;
3735
3736 err = post_relocation(mod, info);
3737 if (err < 0)
3738 goto free_modinfo;
3739
3740 flush_module_icache(mod);
3741
3742 /* Now copy in args */
3743 mod->args = strndup_user(uargs, ~0UL >> 1);
3744 if (IS_ERR(mod->args)) {
3745 err = PTR_ERR(mod->args);
3746 goto free_arch_cleanup;
3747 }
3748
Zhou Chengming52796312017-07-07 11:15:58 +08003749 dynamic_debug_setup(mod, info->debug, info->num_debug);
Kees Cook34e11692012-10-16 07:31:07 +10303750
Steven Rostedt (Red Hat)a949ae52014-04-24 10:40:12 -04003751 /* Ftrace init must be called in the MODULE_STATE_UNFORMED state */
3752 ftrace_module_init(mod);
3753
Rusty Russella3535c72013-01-21 17:18:59 +10303754 /* Finally it's fully formed, ready to start executing. */
3755 err = complete_formation(mod, info);
3756 if (err)
Rusty Russell1fb93412013-01-12 13:27:34 +10303757 goto ddebug_cleanup;
Kees Cook34e11692012-10-16 07:31:07 +10303758
Jessica Yu4c973d12016-03-16 20:55:38 -04003759 err = prepare_coming_module(mod);
3760 if (err)
3761 goto bug_cleanup;
3762
Kees Cook34e11692012-10-16 07:31:07 +10303763 /* Module is ready to execute: parsing args may do that. */
Rusty Russell51e158c2014-04-28 11:34:33 +09303764 after_dashes = parse_args(mod->name, mod->args, mod->kp, mod->num_kp,
Luis R. Rodriguez4355efb2016-02-03 16:55:26 +10303765 -32768, 32767, mod,
Luis R. Rodriguezecc86172015-03-30 16:20:03 -07003766 unknown_module_param_cb);
Rusty Russell51e158c2014-04-28 11:34:33 +09303767 if (IS_ERR(after_dashes)) {
3768 err = PTR_ERR(after_dashes);
Jessica Yu4c973d12016-03-16 20:55:38 -04003769 goto coming_cleanup;
Rusty Russell51e158c2014-04-28 11:34:33 +09303770 } else if (after_dashes) {
3771 pr_warn("%s: parameters '%s' after `--' ignored\n",
3772 mod->name, after_dashes);
3773 }
Kees Cook34e11692012-10-16 07:31:07 +10303774
Richard Guy Briggsca86cad2017-02-04 13:10:38 -05003775 /* Link in to sysfs. */
Kees Cook34e11692012-10-16 07:31:07 +10303776 err = mod_sysfs_setup(mod, info, mod->kp, mod->num_kp);
3777 if (err < 0)
Jessica Yu4c973d12016-03-16 20:55:38 -04003778 goto coming_cleanup;
Kees Cook34e11692012-10-16 07:31:07 +10303779
Jessica Yu1ce15ef2016-03-22 20:03:16 -04003780 if (is_livepatch_module(mod)) {
3781 err = copy_module_elf(mod, info);
3782 if (err < 0)
3783 goto sysfs_cleanup;
3784 }
3785
Kees Cook34e11692012-10-16 07:31:07 +10303786 /* Get rid of temporary copy. */
3787 free_copy(info);
3788
3789 /* Done! */
3790 trace_module_load(mod);
3791
3792 return do_init_module(mod);
3793
Jessica Yu1ce15ef2016-03-22 20:03:16 -04003794 sysfs_cleanup:
3795 mod_sysfs_teardown(mod);
Jessica Yu4c973d12016-03-16 20:55:38 -04003796 coming_cleanup:
Aaron Tomlin885a78d2016-10-20 17:18:12 +01003797 mod->state = MODULE_STATE_GOING;
Luis R. Rodrigueza5544882017-02-10 14:06:22 -08003798 destroy_params(mod->kp, mod->num_kp);
Jessica Yu4c973d12016-03-16 20:55:38 -04003799 blocking_notifier_call_chain(&module_notify_list,
3800 MODULE_STATE_GOING, mod);
Jessica Yu7e545d62016-03-16 20:55:39 -04003801 klp_module_going(mod);
Rusty Russell1fb93412013-01-12 13:27:34 +10303802 bug_cleanup:
3803 /* module_bug_cleanup needs module_mutex protection */
Kees Cook34e11692012-10-16 07:31:07 +10303804 mutex_lock(&module_mutex);
Kees Cook34e11692012-10-16 07:31:07 +10303805 module_bug_cleanup(mod);
Linus Torvaldsee61abb2013-01-20 20:22:58 -08003806 mutex_unlock(&module_mutex);
Andy Lutomirskiff7e0052014-08-16 04:13:37 +09303807
3808 /* we can't deallocate the module until we clear memory protection */
Rusty Russell85c898d2015-11-26 09:45:08 +10303809 module_disable_ro(mod);
3810 module_disable_nx(mod);
Andy Lutomirskiff7e0052014-08-16 04:13:37 +09303811
Rusty Russella3535c72013-01-21 17:18:59 +10303812 ddebug_cleanup:
Namit Gupta1323eac2018-01-08 10:41:21 +05303813 ftrace_release_mod(mod);
Zhou Chengming52796312017-07-07 11:15:58 +08003814 dynamic_debug_remove(mod, info->debug);
Kees Cook34e11692012-10-16 07:31:07 +10303815 synchronize_sched();
3816 kfree(mod->args);
3817 free_arch_cleanup:
3818 module_arch_cleanup(mod);
3819 free_modinfo:
3820 free_modinfo(mod);
3821 free_unload:
3822 module_unload_free(mod);
Rusty Russell1fb93412013-01-12 13:27:34 +10303823 unlink_mod:
3824 mutex_lock(&module_mutex);
3825 /* Unlink carefully: kallsyms could be walking list. */
3826 list_del_rcu(&mod->list);
Peter Zijlstra758556b2015-07-09 06:48:06 +09303827 mod_tree_remove(mod);
Rusty Russell1fb93412013-01-12 13:27:34 +10303828 wake_up_all(&module_wq);
Peter Zijlstra0be964b2015-05-27 11:09:35 +09303829 /* Wait for RCU-sched synchronizing before releasing mod->list. */
3830 synchronize_sched();
Rusty Russell1fb93412013-01-12 13:27:34 +10303831 mutex_unlock(&module_mutex);
Kees Cook34e11692012-10-16 07:31:07 +10303832 free_module:
Peter Zijlstra35a93932015-02-26 16:23:11 +01003833 /* Free lock-classes; relies on the preceding sync_rcu() */
Rusty Russell7523e4d2015-11-26 09:44:08 +10303834 lockdep_free_key_range(mod->core_layout.base, mod->core_layout.size);
Peter Zijlstra35a93932015-02-26 16:23:11 +01003835
Kees Cook34e11692012-10-16 07:31:07 +10303836 module_deallocate(mod, info);
3837 free_copy:
3838 free_copy(info);
3839 return err;
3840}
3841
3842SYSCALL_DEFINE3(init_module, void __user *, umod,
3843 unsigned long, len, const char __user *, uargs)
3844{
3845 int err;
3846 struct load_info info = { };
3847
3848 err = may_init_module();
3849 if (err)
3850 return err;
3851
3852 pr_debug("init_module: umod=%p, len=%lu, uargs=%p\n",
3853 umod, len, uargs);
3854
3855 err = copy_module_from_user(umod, len, &info);
3856 if (err)
3857 return err;
3858
Rusty Russell2f3238a2012-10-22 18:09:41 +10303859 return load_module(&info, uargs, 0);
Kees Cook34e11692012-10-16 07:31:07 +10303860}
3861
Rusty Russell2f3238a2012-10-22 18:09:41 +10303862SYSCALL_DEFINE3(finit_module, int, fd, const char __user *, uargs, int, flags)
Kees Cook34e11692012-10-16 07:31:07 +10303863{
Kees Cook34e11692012-10-16 07:31:07 +10303864 struct load_info info = { };
Mimi Zohara1db7422015-12-30 07:35:30 -05003865 loff_t size;
3866 void *hdr;
3867 int err;
Kees Cook34e11692012-10-16 07:31:07 +10303868
3869 err = may_init_module();
3870 if (err)
3871 return err;
3872
Rusty Russell2f3238a2012-10-22 18:09:41 +10303873 pr_debug("finit_module: fd=%d, uargs=%p, flags=%i\n", fd, uargs, flags);
3874
3875 if (flags & ~(MODULE_INIT_IGNORE_MODVERSIONS
3876 |MODULE_INIT_IGNORE_VERMAGIC))
3877 return -EINVAL;
Kees Cook34e11692012-10-16 07:31:07 +10303878
Mimi Zohara1db7422015-12-30 07:35:30 -05003879 err = kernel_read_file_from_fd(fd, &hdr, &size, INT_MAX,
3880 READING_MODULE);
Kees Cook34e11692012-10-16 07:31:07 +10303881 if (err)
3882 return err;
Mimi Zohara1db7422015-12-30 07:35:30 -05003883 info.hdr = hdr;
3884 info.len = size;
Kees Cook34e11692012-10-16 07:31:07 +10303885
Rusty Russell2f3238a2012-10-22 18:09:41 +10303886 return load_module(&info, uargs, flags);
Kees Cook34e11692012-10-16 07:31:07 +10303887}
3888
Linus Torvalds1da177e2005-04-16 15:20:36 -07003889static inline int within(unsigned long addr, void *start, unsigned long size)
3890{
3891 return ((void *)addr >= start && (void *)addr < start + size);
3892}
3893
3894#ifdef CONFIG_KALLSYMS
3895/*
3896 * This ignores the intensely annoying "mapping symbols" found
3897 * in ARM ELF files: $a, $t and $d.
3898 */
3899static inline int is_arm_mapping_symbol(const char *str)
3900{
Russell King2e3a10a2014-07-27 07:29:01 +09303901 if (str[0] == '.' && str[1] == 'L')
3902 return true;
Kyle McMartin6c34f1f2014-09-16 22:37:18 +01003903 return str[0] == '$' && strchr("axtd", str[1])
Linus Torvalds1da177e2005-04-16 15:20:36 -07003904 && (str[2] == '\0' || str[2] == '.');
3905}
3906
Rusty Russell82440622016-02-03 16:55:26 +10303907static const char *symname(struct mod_kallsyms *kallsyms, unsigned int symnum)
Rusty Russell2e7bac52016-02-03 16:55:26 +10303908{
Rusty Russell82440622016-02-03 16:55:26 +10303909 return kallsyms->strtab + kallsyms->symtab[symnum].st_name;
Rusty Russell2e7bac52016-02-03 16:55:26 +10303910}
3911
Linus Torvalds1da177e2005-04-16 15:20:36 -07003912static const char *get_ksymbol(struct module *mod,
3913 unsigned long addr,
3914 unsigned long *size,
3915 unsigned long *offset)
3916{
3917 unsigned int i, best = 0;
3918 unsigned long nextval;
Rusty Russell82440622016-02-03 16:55:26 +10303919 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003920
3921 /* At worse, next value is at end of module */
Masami Hiramatsua06f6212009-01-06 14:41:49 -08003922 if (within_module_init(addr, mod))
Rusty Russell7523e4d2015-11-26 09:44:08 +10303923 nextval = (unsigned long)mod->init_layout.base+mod->init_layout.text_size;
Daniel Walker22a8bde2007-10-18 03:06:07 -07003924 else
Rusty Russell7523e4d2015-11-26 09:44:08 +10303925 nextval = (unsigned long)mod->core_layout.base+mod->core_layout.text_size;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003926
Lucas De Marchi25985ed2011-03-30 22:57:33 -03003927 /* Scan for closest preceding symbol, and next symbol. (ELF
Daniel Walker22a8bde2007-10-18 03:06:07 -07003928 starts real symbols at 1). */
Rusty Russell82440622016-02-03 16:55:26 +10303929 for (i = 1; i < kallsyms->num_symtab; i++) {
3930 if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003931 continue;
3932
3933 /* We ignore unnamed symbols: they're uninformative
3934 * and inserted at a whim. */
Rusty Russell82440622016-02-03 16:55:26 +10303935 if (*symname(kallsyms, i) == '\0'
3936 || is_arm_mapping_symbol(symname(kallsyms, i)))
Rusty Russell2e7bac52016-02-03 16:55:26 +10303937 continue;
3938
Rusty Russell82440622016-02-03 16:55:26 +10303939 if (kallsyms->symtab[i].st_value <= addr
3940 && kallsyms->symtab[i].st_value > kallsyms->symtab[best].st_value)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003941 best = i;
Rusty Russell82440622016-02-03 16:55:26 +10303942 if (kallsyms->symtab[i].st_value > addr
3943 && kallsyms->symtab[i].st_value < nextval)
3944 nextval = kallsyms->symtab[i].st_value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003945 }
3946
3947 if (!best)
3948 return NULL;
3949
Alexey Dobriyanffb45122007-05-08 00:28:41 -07003950 if (size)
Rusty Russell82440622016-02-03 16:55:26 +10303951 *size = nextval - kallsyms->symtab[best].st_value;
Alexey Dobriyanffb45122007-05-08 00:28:41 -07003952 if (offset)
Rusty Russell82440622016-02-03 16:55:26 +10303953 *offset = addr - kallsyms->symtab[best].st_value;
3954 return symname(kallsyms, best);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003955}
3956
Sergey Senozhatskyb865ea62017-11-10 08:48:25 +09003957void * __weak dereference_module_function_descriptor(struct module *mod,
3958 void *ptr)
3959{
3960 return ptr;
3961}
3962
Rusty Russell6dd06c92008-01-29 17:13:22 -05003963/* For kallsyms to ask for address resolution. NULL means not found. Careful
3964 * not to lock to avoid deadlock on oopses, simply disable preemption. */
Andrew Morton92dfc9d2008-02-08 04:18:43 -08003965const char *module_address_lookup(unsigned long addr,
Rusty Russell6dd06c92008-01-29 17:13:22 -05003966 unsigned long *size,
3967 unsigned long *offset,
3968 char **modname,
3969 char *namebuf)
Linus Torvalds1da177e2005-04-16 15:20:36 -07003970{
Rusty Russellcb2a5202008-01-14 00:55:03 -08003971 const char *ret = NULL;
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303972 struct module *mod;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003973
Rusty Russellcb2a5202008-01-14 00:55:03 -08003974 preempt_disable();
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303975 mod = __module_address(addr);
3976 if (mod) {
3977 if (modname)
3978 *modname = mod->name;
3979 ret = get_ksymbol(mod, addr, size, offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -07003980 }
Rusty Russell6dd06c92008-01-29 17:13:22 -05003981 /* Make a copy in here where it's safe */
3982 if (ret) {
3983 strncpy(namebuf, ret, KSYM_NAME_LEN - 1);
3984 ret = namebuf;
3985 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08003986 preempt_enable();
Peter Zijlstrab7df4d12015-05-27 11:09:37 +09303987
Andrew Morton92dfc9d2008-02-08 04:18:43 -08003988 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07003989}
3990
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07003991int lookup_module_symbol_name(unsigned long addr, char *symname)
3992{
3993 struct module *mod;
3994
Rusty Russellcb2a5202008-01-14 00:55:03 -08003995 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02003996 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10303997 if (mod->state == MODULE_STATE_UNFORMED)
3998 continue;
Petr Mladek9b20a352014-07-27 07:24:01 +09303999 if (within_module(addr, mod)) {
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07004000 const char *sym;
4001
4002 sym = get_ksymbol(mod, addr, NULL, NULL);
4003 if (!sym)
4004 goto out;
Tejun Heo9281ace2007-07-17 04:03:51 -07004005 strlcpy(symname, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08004006 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07004007 return 0;
4008 }
4009 }
4010out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08004011 preempt_enable();
Alexey Dobriyan9d65cb42007-05-08 00:28:43 -07004012 return -ERANGE;
4013}
4014
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07004015int lookup_module_symbol_attrs(unsigned long addr, unsigned long *size,
4016 unsigned long *offset, char *modname, char *name)
4017{
4018 struct module *mod;
4019
Rusty Russellcb2a5202008-01-14 00:55:03 -08004020 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02004021 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304022 if (mod->state == MODULE_STATE_UNFORMED)
4023 continue;
Petr Mladek9b20a352014-07-27 07:24:01 +09304024 if (within_module(addr, mod)) {
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07004025 const char *sym;
4026
4027 sym = get_ksymbol(mod, addr, size, offset);
4028 if (!sym)
4029 goto out;
4030 if (modname)
Tejun Heo9281ace2007-07-17 04:03:51 -07004031 strlcpy(modname, mod->name, MODULE_NAME_LEN);
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07004032 if (name)
Tejun Heo9281ace2007-07-17 04:03:51 -07004033 strlcpy(name, sym, KSYM_NAME_LEN);
Rusty Russellcb2a5202008-01-14 00:55:03 -08004034 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07004035 return 0;
4036 }
4037 }
4038out:
Rusty Russellcb2a5202008-01-14 00:55:03 -08004039 preempt_enable();
Alexey Dobriyana5c43da2007-05-08 00:28:47 -07004040 return -ERANGE;
4041}
4042
Alexey Dobriyanea078902007-05-08 00:28:39 -07004043int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
4044 char *name, char *module_name, int *exported)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004045{
4046 struct module *mod;
4047
Rusty Russellcb2a5202008-01-14 00:55:03 -08004048 preempt_disable();
Andi Kleend72b3752008-08-30 10:09:00 +02004049 list_for_each_entry_rcu(mod, &modules, list) {
Rusty Russell82440622016-02-03 16:55:26 +10304050 struct mod_kallsyms *kallsyms;
4051
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304052 if (mod->state == MODULE_STATE_UNFORMED)
4053 continue;
Rusty Russell82440622016-02-03 16:55:26 +10304054 kallsyms = rcu_dereference_sched(mod->kallsyms);
4055 if (symnum < kallsyms->num_symtab) {
4056 *value = kallsyms->symtab[symnum].st_value;
4057 *type = kallsyms->symtab[symnum].st_info;
4058 strlcpy(name, symname(kallsyms, symnum), KSYM_NAME_LEN);
Tejun Heo9281ace2007-07-17 04:03:51 -07004059 strlcpy(module_name, mod->name, MODULE_NAME_LEN);
Tim Abbottca4787b2009-01-05 08:40:10 -06004060 *exported = is_exported(name, *value, mod);
Rusty Russellcb2a5202008-01-14 00:55:03 -08004061 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07004062 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004063 }
Rusty Russell82440622016-02-03 16:55:26 +10304064 symnum -= kallsyms->num_symtab;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004065 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08004066 preempt_enable();
Alexey Dobriyanea078902007-05-08 00:28:39 -07004067 return -ERANGE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004068}
4069
4070static unsigned long mod_find_symname(struct module *mod, const char *name)
4071{
4072 unsigned int i;
Rusty Russell82440622016-02-03 16:55:26 +10304073 struct mod_kallsyms *kallsyms = rcu_dereference_sched(mod->kallsyms);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004074
Rusty Russell82440622016-02-03 16:55:26 +10304075 for (i = 0; i < kallsyms->num_symtab; i++)
4076 if (strcmp(name, symname(kallsyms, i)) == 0 &&
Jessica Yu9f2d1e62018-06-05 10:22:52 +02004077 kallsyms->symtab[i].st_shndx != SHN_UNDEF)
Rusty Russell82440622016-02-03 16:55:26 +10304078 return kallsyms->symtab[i].st_value;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004079 return 0;
4080}
4081
4082/* Look for this name: can be of form module:name. */
4083unsigned long module_kallsyms_lookup_name(const char *name)
4084{
4085 struct module *mod;
4086 char *colon;
4087 unsigned long ret = 0;
4088
4089 /* Don't lock: we're in enough trouble already. */
Rusty Russellcb2a5202008-01-14 00:55:03 -08004090 preempt_disable();
Naveen N. Rao17586182017-04-23 22:53:43 +05304091 if ((colon = strnchr(name, MODULE_NAME_LEN, ':')) != NULL) {
Mathias Krause4f6de4d52013-07-02 15:35:11 +09304092 if ((mod = find_module_all(name, colon - name, false)) != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004093 ret = mod_find_symname(mod, colon+1);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004094 } else {
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304095 list_for_each_entry_rcu(mod, &modules, list) {
4096 if (mod->state == MODULE_STATE_UNFORMED)
4097 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004098 if ((ret = mod_find_symname(mod, name)) != 0)
4099 break;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304100 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07004101 }
Rusty Russellcb2a5202008-01-14 00:55:03 -08004102 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004103 return ret;
4104}
Anders Kaseorg75a66612008-12-05 19:03:58 -05004105
4106int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
4107 struct module *, unsigned long),
4108 void *data)
4109{
4110 struct module *mod;
4111 unsigned int i;
4112 int ret;
4113
Peter Zijlstra0be964b2015-05-27 11:09:35 +09304114 module_assert_mutex();
4115
Anders Kaseorg75a66612008-12-05 19:03:58 -05004116 list_for_each_entry(mod, &modules, list) {
Rusty Russell82440622016-02-03 16:55:26 +10304117 /* We hold module_mutex: no need for rcu_dereference_sched */
4118 struct mod_kallsyms *kallsyms = mod->kallsyms;
4119
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304120 if (mod->state == MODULE_STATE_UNFORMED)
4121 continue;
Rusty Russell82440622016-02-03 16:55:26 +10304122 for (i = 0; i < kallsyms->num_symtab; i++) {
Jessica Yu9f2d1e62018-06-05 10:22:52 +02004123
4124 if (kallsyms->symtab[i].st_shndx == SHN_UNDEF)
4125 continue;
4126
Rusty Russell82440622016-02-03 16:55:26 +10304127 ret = fn(data, symname(kallsyms, i),
4128 mod, kallsyms->symtab[i].st_value);
Anders Kaseorg75a66612008-12-05 19:03:58 -05004129 if (ret != 0)
4130 return ret;
4131 }
4132 }
4133 return 0;
4134}
Linus Torvalds1da177e2005-04-16 15:20:36 -07004135#endif /* CONFIG_KALLSYMS */
4136
Petr Mladek7fd83292016-09-21 13:47:22 +02004137/* Maximum number of characters written by module_flags() */
4138#define MODULE_FLAGS_BUF_SIZE (TAINT_FLAGS_COUNT + 4)
4139
4140/* Keep in sync with MODULE_FLAGS_BUF_SIZE !!! */
Arjan van de Ven21aa9282008-01-25 21:08:33 +01004141static char *module_flags(struct module *mod, char *buf)
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004142{
4143 int bx = 0;
4144
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304145 BUG_ON(mod->state == MODULE_STATE_UNFORMED);
Arjan van de Ven21aa9282008-01-25 21:08:33 +01004146 if (mod->taints ||
4147 mod->state == MODULE_STATE_GOING ||
4148 mod->state == MODULE_STATE_COMING) {
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004149 buf[bx++] = '(';
Kay Sieverscca3e702012-01-13 09:32:15 +10304150 bx += module_flags_taint(mod, buf + bx);
Arjan van de Ven21aa9282008-01-25 21:08:33 +01004151 /* Show a - for module-is-being-unloaded */
4152 if (mod->state == MODULE_STATE_GOING)
4153 buf[bx++] = '-';
4154 /* Show a + for module-is-being-loaded */
4155 if (mod->state == MODULE_STATE_COMING)
4156 buf[bx++] = '+';
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004157 buf[bx++] = ')';
4158 }
4159 buf[bx] = '\0';
4160
4161 return buf;
4162}
4163
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04004164#ifdef CONFIG_PROC_FS
4165/* Called by the /proc file system to return a list of modules. */
4166static void *m_start(struct seq_file *m, loff_t *pos)
4167{
4168 mutex_lock(&module_mutex);
4169 return seq_list_start(&modules, *pos);
4170}
4171
4172static void *m_next(struct seq_file *m, void *p, loff_t *pos)
4173{
4174 return seq_list_next(p, &modules, pos);
4175}
4176
4177static void m_stop(struct seq_file *m, void *p)
4178{
4179 mutex_unlock(&module_mutex);
4180}
4181
Linus Torvalds1da177e2005-04-16 15:20:36 -07004182static int m_show(struct seq_file *m, void *p)
4183{
4184 struct module *mod = list_entry(p, struct module, list);
Petr Mladek7fd83292016-09-21 13:47:22 +02004185 char buf[MODULE_FLAGS_BUF_SIZE];
Linus Torvalds668533d2017-11-29 10:30:13 -08004186 void *value;
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004187
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304188 /* We always ignore unformed modules. */
4189 if (mod->state == MODULE_STATE_UNFORMED)
4190 return 0;
4191
Denys Vlasenko2f0f2a32008-07-22 19:24:27 -05004192 seq_printf(m, "%s %u",
Rusty Russell7523e4d2015-11-26 09:44:08 +10304193 mod->name, mod->init_layout.size + mod->core_layout.size);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004194 print_unload_info(m, mod);
4195
4196 /* Informative for users. */
4197 seq_printf(m, " %s",
Ionut Alexa6da0b562014-11-10 09:31:29 +10304198 mod->state == MODULE_STATE_GOING ? "Unloading" :
4199 mod->state == MODULE_STATE_COMING ? "Loading" :
Linus Torvalds1da177e2005-04-16 15:20:36 -07004200 "Live");
4201 /* Used by oprofile and other similar tools. */
Linus Torvalds668533d2017-11-29 10:30:13 -08004202 value = m->private ? NULL : mod->core_layout.base;
4203 seq_printf(m, " 0x%px", value);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004204
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004205 /* Taints info */
4206 if (mod->taints)
Arjan van de Ven21aa9282008-01-25 21:08:33 +01004207 seq_printf(m, " %s", module_flags(mod, buf));
Florin Malitafa3ba2e82006-10-11 01:21:48 -07004208
Ionut Alexa6da0b562014-11-10 09:31:29 +10304209 seq_puts(m, "\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07004210 return 0;
4211}
4212
4213/* Format: modulename size refcount deps address
4214
4215 Where refcount is a number or -, and deps is a comma-separated list
4216 of depends or -.
4217*/
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04004218static const struct seq_operations modules_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07004219 .start = m_start,
4220 .next = m_next,
4221 .stop = m_stop,
4222 .show = m_show
4223};
4224
Linus Torvalds516fb7f2017-11-12 18:44:23 -08004225/*
4226 * This also sets the "private" pointer to non-NULL if the
4227 * kernel pointers should be hidden (so you can just test
4228 * "m->private" to see if you should keep the values private).
4229 *
4230 * We use the same logic as for /proc/kallsyms.
4231 */
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04004232static int modules_open(struct inode *inode, struct file *file)
4233{
Linus Torvalds516fb7f2017-11-12 18:44:23 -08004234 int err = seq_open(file, &modules_op);
4235
4236 if (!err) {
4237 struct seq_file *m = file->private_data;
4238 m->private = kallsyms_show_value() ? NULL : (void *)8ul;
4239 }
4240
Leon Yu3f553b32018-03-06 23:16:24 +08004241 return err;
Alexey Dobriyan3b5d5c62008-10-06 13:19:27 +04004242}
4243
4244static const struct file_operations proc_modules_operations = {
4245 .open = modules_open,
4246 .read = seq_read,
4247 .llseek = seq_lseek,
4248 .release = seq_release,
4249};
4250
4251static int __init proc_modules_init(void)
4252{
4253 proc_create("modules", 0, NULL, &proc_modules_operations);
4254 return 0;
4255}
4256module_init(proc_modules_init);
4257#endif
4258
Linus Torvalds1da177e2005-04-16 15:20:36 -07004259/* Given an address, look for it in the module exception tables. */
4260const struct exception_table_entry *search_module_extables(unsigned long addr)
4261{
Linus Torvalds1da177e2005-04-16 15:20:36 -07004262 const struct exception_table_entry *e = NULL;
4263 struct module *mod;
4264
Rusty Russell24da1cb2007-07-15 23:41:46 -07004265 preempt_disable();
Peter Zijlstra5ff22642017-02-08 15:48:01 +01004266 mod = __module_address(addr);
4267 if (!mod)
4268 goto out;
Daniel Walker22a8bde2007-10-18 03:06:07 -07004269
Peter Zijlstra5ff22642017-02-08 15:48:01 +01004270 if (!mod->num_exentries)
4271 goto out;
4272
4273 e = search_extable(mod->extable,
Thomas Meyera94c33d2017-07-10 15:51:58 -07004274 mod->num_exentries,
Peter Zijlstra5ff22642017-02-08 15:48:01 +01004275 addr);
4276out:
Rusty Russell24da1cb2007-07-15 23:41:46 -07004277 preempt_enable();
Linus Torvalds1da177e2005-04-16 15:20:36 -07004278
Peter Zijlstra5ff22642017-02-08 15:48:01 +01004279 /*
4280 * Now, if we found one, we are running inside it now, hence
4281 * we cannot unload the module, hence no refcnt needed.
4282 */
Linus Torvalds1da177e2005-04-16 15:20:36 -07004283 return e;
4284}
4285
Ingo Molnar4d435f92006-07-03 00:24:24 -07004286/*
Rusty Russelle6104992009-03-31 13:05:31 -06004287 * is_module_address - is this address inside a module?
4288 * @addr: the address to check.
4289 *
4290 * See is_module_text_address() if you simply want to see if the address
4291 * is code (not data).
Ingo Molnar4d435f92006-07-03 00:24:24 -07004292 */
Rusty Russelle6104992009-03-31 13:05:31 -06004293bool is_module_address(unsigned long addr)
Ingo Molnar4d435f92006-07-03 00:24:24 -07004294{
Rusty Russelle6104992009-03-31 13:05:31 -06004295 bool ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07004296
Rusty Russell24da1cb2007-07-15 23:41:46 -07004297 preempt_disable();
Rusty Russelle6104992009-03-31 13:05:31 -06004298 ret = __module_address(addr) != NULL;
Rusty Russell24da1cb2007-07-15 23:41:46 -07004299 preempt_enable();
Ingo Molnar4d435f92006-07-03 00:24:24 -07004300
Rusty Russelle6104992009-03-31 13:05:31 -06004301 return ret;
Ingo Molnar4d435f92006-07-03 00:24:24 -07004302}
4303
Rusty Russelle6104992009-03-31 13:05:31 -06004304/*
4305 * __module_address - get the module which contains an address.
4306 * @addr: the address.
4307 *
4308 * Must be called with preempt disabled or module mutex held so that
4309 * module doesn't get freed during this.
4310 */
Linus Torvalds714f83d2009-04-05 11:04:19 -07004311struct module *__module_address(unsigned long addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07004312{
4313 struct module *mod;
4314
Rusty Russell3a642e92008-07-22 19:24:28 -05004315 if (addr < module_addr_min || addr > module_addr_max)
4316 return NULL;
4317
Peter Zijlstra0be964b2015-05-27 11:09:35 +09304318 module_assert_mutex_or_preempt();
4319
Peter Zijlstra6c9692e2015-05-27 11:09:37 +09304320 mod = mod_find(addr);
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304321 if (mod) {
4322 BUG_ON(!within_module(addr, mod));
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304323 if (mod->state == MODULE_STATE_UNFORMED)
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304324 mod = NULL;
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304325 }
Peter Zijlstra93c2e102015-05-27 11:09:37 +09304326 return mod;
Linus Torvalds1da177e2005-04-16 15:20:36 -07004327}
Tim Abbottc6b37802008-12-05 19:03:59 -05004328EXPORT_SYMBOL_GPL(__module_address);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004329
Rusty Russelle6104992009-03-31 13:05:31 -06004330/*
4331 * is_module_text_address - is this address inside module code?
4332 * @addr: the address to check.
4333 *
4334 * See is_module_address() if you simply want to see if the address is
4335 * anywhere in a module. See kernel_text_address() for testing if an
4336 * address corresponds to kernel or module code.
4337 */
4338bool is_module_text_address(unsigned long addr)
4339{
4340 bool ret;
4341
4342 preempt_disable();
4343 ret = __module_text_address(addr) != NULL;
4344 preempt_enable();
4345
4346 return ret;
4347}
4348
4349/*
4350 * __module_text_address - get the module whose code contains an address.
4351 * @addr: the address.
4352 *
4353 * Must be called with preempt disabled or module mutex held so that
4354 * module doesn't get freed during this.
4355 */
4356struct module *__module_text_address(unsigned long addr)
4357{
4358 struct module *mod = __module_address(addr);
4359 if (mod) {
4360 /* Make sure it's within the text section. */
Rusty Russell7523e4d2015-11-26 09:44:08 +10304361 if (!within(addr, mod->init_layout.base, mod->init_layout.text_size)
4362 && !within(addr, mod->core_layout.base, mod->core_layout.text_size))
Rusty Russelle6104992009-03-31 13:05:31 -06004363 mod = NULL;
4364 }
4365 return mod;
4366}
Tim Abbottc6b37802008-12-05 19:03:59 -05004367EXPORT_SYMBOL_GPL(__module_text_address);
Rusty Russelle6104992009-03-31 13:05:31 -06004368
Linus Torvalds1da177e2005-04-16 15:20:36 -07004369/* Don't grab lock, we're oopsing. */
4370void print_modules(void)
4371{
4372 struct module *mod;
Petr Mladek7fd83292016-09-21 13:47:22 +02004373 char buf[MODULE_FLAGS_BUF_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -07004374
Linus Torvaldsb2311252009-06-16 11:07:14 -07004375 printk(KERN_DEFAULT "Modules linked in:");
Andi Kleend72b3752008-08-30 10:09:00 +02004376 /* Most callers should already have preempt disabled, but make sure */
4377 preempt_disable();
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304378 list_for_each_entry_rcu(mod, &modules, list) {
4379 if (mod->state == MODULE_STATE_UNFORMED)
4380 continue;
Jiri Slaby27bba4d2014-02-03 11:13:13 +10304381 pr_cont(" %s%s", mod->name, module_flags(mod, buf));
Rusty Russell0d21b0e2013-01-12 11:38:44 +10304382 }
Andi Kleend72b3752008-08-30 10:09:00 +02004383 preempt_enable();
Arjan van de Vene14af7e2008-01-25 21:08:33 +01004384 if (last_unloaded_module[0])
Jiri Slaby27bba4d2014-02-03 11:13:13 +10304385 pr_cont(" [last unloaded: %s]", last_unloaded_module);
4386 pr_cont("\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -07004387}
4388
Linus Torvalds1da177e2005-04-16 15:20:36 -07004389#ifdef CONFIG_MODVERSIONS
Rusty Russell8c8ef422009-03-31 13:05:34 -06004390/* Generate the signature for all relevant module structures here.
4391 * If these change, we don't want to try to parse the module. */
4392void module_layout(struct module *mod,
4393 struct modversion_info *ver,
4394 struct kernel_param *kp,
4395 struct kernel_symbol *ks,
Mathieu Desnoyers65498642011-01-26 17:26:22 -05004396 struct tracepoint * const *tp)
Rusty Russell8c8ef422009-03-31 13:05:34 -06004397{
4398}
4399EXPORT_SYMBOL(module_layout);
Linus Torvalds1da177e2005-04-16 15:20:36 -07004400#endif