diff options
| author | Matthew Wilcox (Oracle) | 2021-11-05 13:35:53 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2021-11-06 13:30:33 -0700 |
| commit | 820a1e6e87ccaa6c0c77ac7d79d05beec3f8cb88 (patch) | |
| tree | 63574d9076436d646ac4f95ccd1ce5d7c4280716 | |
| parent | f70da745be4d4c367568b8345f50db1ae04efcb2 (diff) | |
kasan: fix tag for large allocations when using CONFIG_SLAB
If an object is allocated on a tail page of a multi-page slab, kasan
will get the wrong tag because page->s_mem is NULL for tail pages. I'm
not quite sure what the user-visible effect of this might be.
Link: https://lkml.kernel.org/r/20211001024105.3217339-1-willy@infradead.org
Fixes: 7f94ffbc4c6a ("kasan: add hooks implementation for tag-based mode")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | mm/kasan/common.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 3e0999892c36..8428da2aaf17 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -298,7 +298,7 @@ static inline u8 assign_tag(struct kmem_cache *cache, /* For caches that either have a constructor or SLAB_TYPESAFE_BY_RCU: */ #ifdef CONFIG_SLAB /* For SLAB assign tags based on the object index in the freelist. */ - return (u8)obj_to_index(cache, virt_to_page(object), (void *)object); + return (u8)obj_to_index(cache, virt_to_head_page(object), (void *)object); #else /* * For SLUB assign a random tag during slab creation, otherwise reuse |