diff options
Diffstat (limited to 'mm/slab.h')
| -rw-r--r-- | mm/slab.h | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/mm/slab.h b/mm/slab.h index 0202a8c2f0d2..2642102f6699 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -720,13 +720,27 @@ static inline struct kmem_cache *slab_pre_alloc_hook(struct kmem_cache *s, static inline void slab_post_alloc_hook(struct kmem_cache *s, struct obj_cgroup *objcg, gfp_t flags, - size_t size, void **p, bool init) + size_t size, void **p, bool init, + unsigned int orig_size) { + unsigned int zero_size = s->object_size; size_t i; flags &= gfp_allowed_mask; /* + * For kmalloc object, the allocated memory size(object_size) is likely + * larger than the requested size(orig_size). If redzone check is + * enabled for the extra space, don't zero it, as it will be redzoned + * soon. The redzone operation for this extra space could be seen as a + * replacement of current poisoning under certain debug option, and + * won't break other sanity checks. + */ + if (kmem_cache_debug_flags(s, SLAB_STORE_USER | SLAB_RED_ZONE) && + (s->flags & SLAB_KMALLOC)) + zero_size = orig_size; + + /* * As memory initialization might be integrated into KASAN, * kasan_slab_alloc and initialization memset must be * kept together to avoid discrepancies in behavior. @@ -736,7 +750,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, for (i = 0; i < size; i++) { p[i] = kasan_slab_alloc(s, p[i], flags, init); if (p[i] && init && !kasan_has_integrated_init()) - memset(p[i], 0, s->object_size); + memset(p[i], 0, zero_size); kmemleak_alloc_recursive(p[i], s->object_size, 1, s->flags, flags); kmsan_slab_alloc(s, p[i], flags); |