diff options
| author | Andrey Konovalov <andreyknvl@google.com> | 2017-05-03 14:56:34 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-05-03 15:52:12 -0700 |
| commit | db429f16e0b472292000fd53b63ebd7221a9856e (patch) | |
| tree | 620b88b09d6fda9530222fc93fa1dd5e163ac229 /mm/kasan | |
| parent | b6b72f4919c121bee5890732e0b8de2ab99c8dbc (diff) | |
kasan: simplify address description logic
Simplify logic for describing a memory address. Add addr_to_page()
helper function.
Makes the code easier to follow.
Link: http://lkml.kernel.org/r/20170302134851.101218-5-andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/kasan')
| -rw-r--r-- | mm/kasan/report.c | 37 |
1 files changed, 21 insertions, 16 deletions
diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 7d24363edd66..a82d6896062b 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -190,11 +190,18 @@ static void print_track(struct kasan_track *track, const char *prefix) } } -static void kasan_object_err(struct kmem_cache *cache, void *object) +static struct page *addr_to_page(const void *addr) +{ + if ((addr >= (void *)PAGE_OFFSET) && + (addr < high_memory)) + return virt_to_head_page(addr); + return NULL; +} + +static void describe_object(struct kmem_cache *cache, void *object) { struct kasan_alloc_meta *alloc_info = get_alloc_info(cache, object); - dump_stack(); pr_err("Object at %p, in cache %s size: %d\n", object, cache->name, cache->object_size); @@ -213,34 +220,32 @@ void kasan_report_double_free(struct kmem_cache *cache, void *object, kasan_start_report(&flags); pr_err("BUG: Double free or freeing an invalid pointer\n"); pr_err("Unexpected shadow byte: 0x%hhX\n", shadow); - kasan_object_err(cache, object); + dump_stack(); + describe_object(cache, object); kasan_end_report(&flags); } static void print_address_description(struct kasan_access_info *info) { const void *addr = info->access_addr; + struct page *page = addr_to_page(addr); - if ((addr >= (void *)PAGE_OFFSET) && - (addr < high_memory)) { - struct page *page = virt_to_head_page(addr); - - if (PageSlab(page)) { - void *object; - struct kmem_cache *cache = page->slab_cache; - object = nearest_obj(cache, page, - (void *)info->access_addr); - kasan_object_err(cache, object); - return; - } + if (page) dump_page(page, "kasan: bad access detected"); + + dump_stack(); + + if (page && PageSlab(page)) { + struct kmem_cache *cache = page->slab_cache; + void *object = nearest_obj(cache, page, (void *)addr); + + describe_object(cache, object); } if (kernel_or_module_addr(addr)) { if (!init_task_stack_addr(addr)) pr_err("Address belongs to variable %pS\n", addr); } - dump_stack(); } static bool row_is_guilty(const void *row, const void *guilty) |