diff options
Diffstat (limited to 'mm/slab.h')
| -rw-r--r-- | mm/slab.h | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/mm/slab.h b/mm/slab.h index 6a5633b25eb5..9c0e09d0f81f 100644 --- a/mm/slab.h +++ b/mm/slab.h @@ -723,6 +723,7 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, unsigned int orig_size) { unsigned int zero_size = s->object_size; + bool kasan_init = init; size_t i; flags &= gfp_allowed_mask; @@ -740,6 +741,17 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, zero_size = orig_size; /* + * When slub_debug is enabled, avoid memory initialization integrated + * into KASAN and instead zero out the memory via the memset below with + * the proper size. Otherwise, KASAN might overwrite SLUB redzones and + * cause false-positive reports. This does not lead to a performance + * penalty on production builds, as slub_debug is not intended to be + * enabled there. + */ + if (__slub_debug_enabled()) + kasan_init = false; + + /* * As memory initialization might be integrated into KASAN, * kasan_slab_alloc and initialization memset must be * kept together to avoid discrepancies in behavior. @@ -747,8 +759,8 @@ static inline void slab_post_alloc_hook(struct kmem_cache *s, * As p[i] might get tagged, memset and kmemleak hook come after KASAN. */ for (i = 0; i < size; i++) { - p[i] = kasan_slab_alloc(s, p[i], flags, init); - if (p[i] && init && !kasan_has_integrated_init()) + p[i] = kasan_slab_alloc(s, p[i], flags, kasan_init); + if (p[i] && init && (!kasan_init || !kasan_has_integrated_init())) memset(p[i], 0, zero_size); kmemleak_alloc_recursive(p[i], s->object_size, 1, s->flags, flags); |