[PATCH 02/11] mpx: extend siginfo structure to include bound violation information

Dave Hansen
2014-11-14T15:18:19Z

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>
---

b/include/uapi/asm-generic/siginfo.h | 9 ++++++++-
b/kernel/signal.c | 4 ++++
2 files changed, 12 insertions(+), 1 deletion(-)

diff -puN include/uapi/asm-generic/siginfo.h~mpx-v11-mpx-extend-siginfo-structure-to-include-bound-violation-information include/uapi/asm-generic/siginfo.h
--- a/include/uapi/asm-generic/siginfo.h~mpx-v11-mpx-extend-siginfo-structure-to-include-bound-violation-information 2014-11-14 07:06:21.148558419 -0800
+++ b/include/uapi/asm-generic/siginfo.h 2014-11-14 07:06:21.153558645 -0800
@@ -91,6 +91,10 @@ typedef struct siginfo {
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 @@ typedef struct siginfo {
#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 @@ typedef struct siginfo {
*/
#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
diff -puN kernel/signal.c~mpx-v11-mpx-extend-siginfo-structure-to-include-bound-violation-information kernel/signal.c
--- a/kernel/signal.c~mpx-v11-mpx-extend-siginfo-structure-to-include-bound-violation-information 2014-11-14 07:06:21.150558509 -0800
+++ b/kernel/signal.c 2014-11-14 07:06:21.155558734 -0800
@@ -2748,6 +2748,10 @@ int copy_siginfo_to_user(siginfo_t __use
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);
_