From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Subject: mm/kasan: get rid of ->alloc_size in struct kasan_alloc_meta Size of slab object already stored in cache->object_size. Note, that kmalloc() internally rounds up size of allocation, so object_size may be not equal to alloc_size, but, usually we don't need to know the exact size of allocated object. In case if we need that information, we still can figure it out from the report. The dump of shadow memory allows to identify the end of allocated memory, and thereby the exact allocation size. Link: http://lkml.kernel.org/r/1470062715-14077-4-git-send-email-aryabinin@xxxxxxxxxxxxx Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/kasan/kasan.c | 1 - mm/kasan/kasan.h | 3 +-- mm/kasan/report.c | 8 +++----- 3 files changed, 4 insertions(+), 8 deletions(-) diff -puN mm/kasan/kasan.c~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta mm/kasan/kasan.c --- a/mm/kasan/kasan.c~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta +++ a/mm/kasan/kasan.c @@ -584,7 +584,6 @@ void kasan_kmalloc(struct kmem_cache *ca get_alloc_info(cache, object); alloc_info->state = KASAN_STATE_ALLOC; - alloc_info->alloc_size = size; set_track(&alloc_info->track, flags); } } diff -puN mm/kasan/kasan.h~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta mm/kasan/kasan.h --- a/mm/kasan/kasan.h~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta +++ a/mm/kasan/kasan.h @@ -75,8 +75,7 @@ struct kasan_track { struct kasan_alloc_meta { struct kasan_track track; - u32 state : 2; /* enum kasan_state */ - u32 alloc_size : 30; + u32 state; }; struct qlist_node { diff -puN mm/kasan/report.c~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta mm/kasan/report.c --- a/mm/kasan/report.c~mm-kasan-get-rid-of-alloc_size-in-struct-kasan_alloc_meta +++ a/mm/kasan/report.c @@ -136,7 +136,9 @@ static void kasan_object_err(struct kmem struct kasan_free_meta *free_info; dump_stack(); - pr_err("Object at %p, in cache %s\n", object, cache->name); + pr_err("Object at %p, in cache %s size: %d\n", object, cache->name, + cache->object_size); + if (!(cache->flags & SLAB_KASAN)) return; switch (alloc_info->state) { @@ -144,15 +146,11 @@ static void kasan_object_err(struct kmem pr_err("Object not allocated yet\n"); break; case KASAN_STATE_ALLOC: - pr_err("Object allocated with size %u bytes.\n", - alloc_info->alloc_size); pr_err("Allocation:\n"); print_track(&alloc_info->track); break; case KASAN_STATE_FREE: case KASAN_STATE_QUARANTINE: - pr_err("Object freed, allocated with size %u bytes\n", - alloc_info->alloc_size); free_info = get_free_info(cache, object); pr_err("Allocation:\n"); print_track(&alloc_info->track); _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
