Infrastructure management of the cred security blob
Move management of the cred security blob out of the
security modules and into the security infrastructre.
Instead of allocating and freeing space the security
modules tell the infrastructure how much space they
require.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[kees: adjusted for ordered init series]
Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 169cf5b..239b13b4 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -210,12 +210,9 @@
struct cred *cred = (struct cred *) current->real_cred;
struct task_security_struct *tsec;
- tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
- if (!tsec)
- panic("SELinux: Failed to initialize initial task.\n");
-
+ lsm_early_cred(cred);
+ tsec = selinux_cred(cred);
tsec->osid = tsec->sid = SECINITSID_KERNEL;
- cred->security = tsec;
}
/*
@@ -3686,46 +3683,15 @@
}
/*
- * allocate the SELinux part of blank credentials
- */
-static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
-{
- struct task_security_struct *tsec;
-
- tsec = kzalloc(sizeof(struct task_security_struct), gfp);
- if (!tsec)
- return -ENOMEM;
-
- cred->security = tsec;
- return 0;
-}
-
-/*
- * detach and free the LSM part of a set of credentials
- */
-static void selinux_cred_free(struct cred *cred)
-{
- struct task_security_struct *tsec = selinux_cred(cred);
-
- kfree(tsec);
-}
-
-/*
* prepare a new set of credentials for modification
*/
static int selinux_cred_prepare(struct cred *new, const struct cred *old,
gfp_t gfp)
{
- const struct task_security_struct *old_tsec;
- struct task_security_struct *tsec;
+ const struct task_security_struct *old_tsec = selinux_cred(old);
+ struct task_security_struct *tsec = selinux_cred(new);
- old_tsec = selinux_cred(old);
-
- tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
- if (!tsec)
- return -ENOMEM;
-
- new->security = tsec;
+ *tsec = *old_tsec;
return 0;
}
@@ -6678,6 +6644,10 @@
}
#endif
+struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
+ .lbs_cred = sizeof(struct task_security_struct),
+};
+
static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
@@ -6761,8 +6731,6 @@
LSM_HOOK_INIT(file_open, selinux_file_open),
LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
- LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
- LSM_HOOK_INIT(cred_free, selinux_cred_free),
LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
@@ -6981,6 +6949,7 @@
.name = "selinux",
.flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
.enabled = &selinux_enabled,
+ .blobs = &selinux_blob_sizes,
.init = selinux_init,
};