commit ee1b58d36aa1b5a79eaba11f5c3633c88231da83
author Qiaowei Ren <qiaowei.ren@intel.com> Fri Nov 14 07:18:19 2014 -0800
committer Thomas Gleixner <tglx@linutronix.de> Tue Nov 18 00:58:53 2014 +0100
tree c27ee172205f77faf191d3112b5a88d688c722c4
parent 62e7759b1bdaf9b753c3724a56fcbe3235ebd5f3

mpx: Extend siginfo structure to include bound violation information

This patch adds new fields about bound violation into siginfo
structure. si_lower and si_upper are respectively lower bound
and upper bound when bound violation is caused.

Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-mm@kvack.org
Cc: linux-mips@linux-mips.org
Cc: Dave Hansen <dave@sr71.net>
Link: http://lkml.kernel.org/r/20141114151819.1908C900@viggo.jf.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

include/uapi/asm-generic/siginfo.h

diff --git a/include/uapi/asm-generic/siginfo.h b/include/uapi/asm-generic/siginfo.h
index ba5be7f..1e35520 100644
--- a/include/uapi/asm-generic/siginfo.h
+++ b/include/uapi/asm-generic/siginfo.h
@@ -91,6 +91,10 @@
 			int _trapno;	/* TRAP # which caused the signal */
 #endif
 			short _addr_lsb; /* LSB of the reported address */
+			struct {
+				void __user *_lower;
+				void __user *_upper;
+			} _addr_bnd;
 		} _sigfault;
 
 		/* SIGPOLL */
@@ -131,6 +135,8 @@
 #define si_trapno	_sifields._sigfault._trapno
 #endif
 #define si_addr_lsb	_sifields._sigfault._addr_lsb
+#define si_lower	_sifields._sigfault._addr_bnd._lower
+#define si_upper	_sifields._sigfault._addr_bnd._upper
 #define si_band		_sifields._sigpoll._band
 #define si_fd		_sifields._sigpoll._fd
 #ifdef __ARCH_SIGSYS
@@ -199,7 +205,8 @@
  */
 #define SEGV_MAPERR	(__SI_FAULT|1)	/* address not mapped to object */
 #define SEGV_ACCERR	(__SI_FAULT|2)	/* invalid permissions for mapped object */
-#define NSIGSEGV	2
+#define SEGV_BNDERR	(__SI_FAULT|3)  /* failed address bound checks */
+#define NSIGSEGV	3
 
 /*
  * SIGBUS si_codes

kernel/signal.c

diff --git a/kernel/signal.c b/kernel/signal.c
index 8f0876f..2c403a4 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -2748,6 +2748,10 @@
 		if (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO)
 			err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
 #endif
+#ifdef SEGV_BNDERR
+		err |= __put_user(from->si_lower, &to->si_lower);
+		err |= __put_user(from->si_upper, &to->si_upper);
+#endif
 		break;
 	case __SI_CHLD:
 		err |= __put_user(from->si_pid, &to->si_pid);