This is a note to let you know that I've just added the patch titled mm, kasan: account for object redzone in SLUB's nearest_obj() to the 4.7-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: mm-kasan-account-for-object-redzone-in-slub-s-nearest_obj.patch and it can be found in the queue-4.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c146a2b98eb5898eb0fab15a332257a4102ecae9 Mon Sep 17 00:00:00 2001 From: Alexander Potapenko <glider@xxxxxxxxxx> Date: Thu, 28 Jul 2016 15:49:04 -0700 Subject: mm, kasan: account for object redzone in SLUB's nearest_obj() From: Alexander Potapenko <glider@xxxxxxxxxx> commit c146a2b98eb5898eb0fab15a332257a4102ecae9 upstream. When looking up the nearest SLUB object for a given address, correctly calculate its offset if SLAB_RED_ZONE is enabled for that cache. Previously, when KASAN had detected an error on an object from a cache with SLAB_RED_ZONE set, the actual start address of the object was miscalculated, which led to random stacks having been reported. When looking up the nearest SLUB object for a given address, correctly calculate its offset if SLAB_RED_ZONE is enabled for that cache. Fixes: 7ed2f9e663854db ("mm, kasan: SLAB support") Link: http://lkml.kernel.org/r/1468347165-41906-2-git-send-email-glider@xxxxxxxxxx Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <adech.fo@xxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Steven Rostedt (Red Hat) <rostedt@xxxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Kostya Serebryany <kcc@xxxxxxxxxx> Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Kuthonuzo Luruo <kuthonuzo.luruo@xxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- include/linux/slub_def.h | 10 ++++++---- mm/slub.c | 2 +- 2 files changed, 7 insertions(+), 5 deletions(-) --- a/include/linux/slub_def.h +++ b/include/linux/slub_def.h @@ -114,15 +114,17 @@ static inline void sysfs_slab_remove(str void object_err(struct kmem_cache *s, struct page *page, u8 *object, char *reason); +void *fixup_red_left(struct kmem_cache *s, void *p); + static inline void *nearest_obj(struct kmem_cache *cache, struct page *page, void *x) { void *object = x - (x - page_address(page)) % cache->size; void *last_object = page_address(page) + (page->objects - 1) * cache->size; - if (unlikely(object > last_object)) - return last_object; - else - return object; + void *result = (unlikely(object > last_object)) ? last_object : object; + + result = fixup_red_left(cache, result); + return result; } #endif /* _LINUX_SLUB_DEF_H */ --- a/mm/slub.c +++ b/mm/slub.c @@ -124,7 +124,7 @@ static inline int kmem_cache_debug(struc #endif } -static inline void *fixup_red_left(struct kmem_cache *s, void *p) +inline void *fixup_red_left(struct kmem_cache *s, void *p) { if (kmem_cache_debug(s) && s->flags & SLAB_RED_ZONE) p += s->red_left_pad; Patches currently in stable-queue which might be from glider@xxxxxxxxxx are queue-4.7/mm-kasan-account-for-object-redzone-in-slub-s-nearest_obj.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html