diff options
| author | Vasily Kulikov <segoon@openwall.com> | 2015-09-09 15:36:00 -0700 |
|---|---|---|
| committer | Trafalgar Square <schneller.demian@gmail.com> | 2016-03-22 16:01:32 +0100 |
| commit | bc3f45b640f354c7d1630c4fa06efe65cc7ff8ec (patch) | |
| tree | f057eddcfe66742ca3c623e57c0c83479dd0f97d | |
| parent | 6568922a5b3b700a5485ec73fbb257d466b02af0 (diff) | |
UPSTREAM: include/linux/poison.h: fix LIST_POISON{1,2} offsetmm6.0
(cherry pick from commit 8a5e5e02fc83aaf67053ab53b359af08c6c49aaf)
Poison pointer values should be small enough to find a room in
non-mmap'able/hardly-mmap'able space. E.g. on x86 "poison pointer space"
is located starting from 0x0. Given unprivileged users cannot mmap
anything below mmap_min_addr, it should be safe to use poison pointers
lower than mmap_min_addr.
The current poison pointer values of LIST_POISON{1,2} might be too big for
mmap_min_addr values equal or less than 1 MB (common case, e.g. Ubuntu
uses only 0x10000). There is little point to use such a big value given
the "poison pointer space" below 1 MB is not yet exhausted. Changing it
to a smaller value solves the problem for small mmap_min_addr setups.
The values are suggested by Solar Designer:
http://www.openwall.com/lists/oss-security/2015/05/02/6
Signed-off-by: Vasily Kulikov <segoon@openwall.com>
Cc: Solar Designer <solar@openwall.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Bug: 26429468
Bug: 26186802
Bug: 26429519
Bug: PAELLA-182
Change-Id: Ic51614f6cc98e416282f19af96b9d116eff7c08b
| -rw-r--r-- | include/linux/poison.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/poison.h b/include/linux/poison.h index 79159de0e34..eae9c383e7c 100644 --- a/include/linux/poison.h +++ b/include/linux/poison.h @@ -19,8 +19,8 @@ * under normal circumstances, used to verify that nobody uses * non-initialized list entries. */ -#define LIST_POISON1 ((void *) 0x00100100 + POISON_POINTER_DELTA) -#define LIST_POISON2 ((void *) 0x00200200 + POISON_POINTER_DELTA) +#define LIST_POISON1 ((void *) 0x100 + POISON_POINTER_DELTA) +#define LIST_POISON2 ((void *) 0x200 + POISON_POINTER_DELTA) /********** include/linux/timer.h **********/ /* |