diff options
| author | Se Wang (Patrick) Oh <sewango@codeaurora.org> | 2015-06-25 15:55:04 -0700 |
|---|---|---|
| committer | David Keitel <dkeitel@codeaurora.org> | 2016-03-22 11:10:45 -0700 |
| commit | 1ee3c679cd8339f61aac3392cc1711f352895d1d (patch) | |
| tree | 6bf2d0bbd1ccb3d7b95e532c2591a4e1cf1a8430 /mm/slub.c | |
| parent | dae9a397e1d3d92b6f44f248972350cbc16828b5 (diff) | |
mm: slub: call kasan_alloc_pages before freeing pages in slub
KASan marks slub objects as redzone and free and the bitmasks for
that region are not cleared until the pages are freed. When
CONFIG_PAGE_POISONING is enabled, as the pages still have special
bitmasks, KAsan report arises during pages poisoning. So mark the
pages as alloc status before poisoning the pages.
==================================================================
BUG: KASan: use after free in memset+0x24/0x44 at addr ffffffc0bb628000
Write of size 4096 by task kworker/u8:0/6
page:ffffffbacc51d900 count:0 mapcount:0 mapping: (null) index:0x0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected
Call trace:
[<ffffffc00008c010>] dump_backtrace+0x0/0x250
[<ffffffc00008c270>] show_stack+0x10/0x1c
[<ffffffc001b6f9e4>] dump_stack+0x74/0xfc
[<ffffffc0002debf4>] kasan_report_error+0x2b0/0x408
[<ffffffc0002dee28>] kasan_report+0x34/0x40
[<ffffffc0002de240>] __asan_storeN+0x15c/0x168
[<ffffffc0002de47c>] memset+0x20/0x44
[<ffffffc0002d77bc>] kernel_map_pages+0x2e8/0x384
[<ffffffc000266458>] free_pages_prepare+0x340/0x3a0
[<ffffffc0002694cc>] __free_pages_ok+0x20/0x12c
[<ffffffc00026a698>] __free_pages+0x34/0x44
[<ffffffc00026ab3c>] __free_kmem_pages+0x8/0x14
[<ffffffc0002dc3fc>] kfree+0x114/0x254
[<ffffffc000b05748>] devres_free+0x48/0x5c
[<ffffffc000b05824>] devres_destroy+0x10/0x28
[<ffffffc000b05958>] devm_kfree+0x1c/0x3c
Memory state around the buggy address:
ffffffc0bb627f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffffc0bb627f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffc0bb628000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
^
ffffffc0bb628080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
ffffffc0bb628100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
BUG: KASan: use after free in memset+0x24/0x44 at addr ffffffc0bb2fe000
Write of size 4096 by task swapper/0/1
page:ffffffbacc4fdec0 count:0 mapcount:0 mapping: (null) index:0xffffffc0bb2fe6a0
flags: 0x4000000000000000()
page dumped because: kasan: bad access detected
Call trace:
[<ffffffc00008c010>] dump_backtrace+0x0/0x250
[<ffffffc00008c270>] show_stack+0x10/0x1c
[<ffffffc001b6f9e4>] dump_stack+0x74/0xfc
[<ffffffc0002debf4>] kasan_report_error+0x2b0/0x408
[<ffffffc0002dee28>] kasan_report+0x34/0x40
[<ffffffc0002de240>] __asan_storeN+0x15c/0x168
[<ffffffc0002de47c>] memset+0x20/0x44
[<ffffffc0002d77bc>] kernel_map_pages+0x2e8/0x384
[<ffffffc000266458>] free_pages_prepare+0x340/0x3a0
[<ffffffc0002694cc>] __free_pages_ok+0x20/0x12c
[<ffffffc00026a698>] __free_pages+0x34/0x44
[<ffffffc0002d9c98>] __free_slab+0x15c/0x178
[<ffffffc0002d9d14>] discard_slab+0x60/0x6c
[<ffffffc0002dc034>] __slab_free+0x320/0x340
[<ffffffc0002dc224>] kmem_cache_free+0x1d0/0x25c
[<ffffffc0003bb608>] kernfs_put+0x2a0/0x3d8
Memory state around the buggy address:
ffffffc0bb2fdf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffffffc0bb2fdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffffffc0bb2fe000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
^
fffffc0bb2fe080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffffffc0bb2fe100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Change-Id: Id963b9439685f94a022dcdd60b59aaf126610387
Signed-off-by: Se Wang (Patrick) Oh <sewango@codeaurora.org>
[satyap: trivial merge conflict resolution]
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>
Diffstat (limited to 'mm/slub.c')
| -rw-r--r-- | mm/slub.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/slub.c b/mm/slub.c index f12102b4aef9..2d5bbea0f0e8 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1538,6 +1538,7 @@ static void __free_slab(struct kmem_cache *s, struct page *page) page_mapcount_reset(page); if (current->reclaim_state) current->reclaim_state->reclaimed_slab += pages; + kasan_alloc_pages(page, order); __free_kmem_pages(page, order); } @@ -3638,6 +3639,7 @@ void kfree(const void *x) if (unlikely(!PageSlab(page))) { BUG_ON(!PageCompound(page)); kfree_hook(x); + kasan_alloc_pages(page, compound_order(page)); __free_kmem_pages(page, compound_order(page)); return; } |