linux/fs/f2fs
Chao Yu b862676e37 f2fs: fix to avoid out-of-bounds memory access
butt3rflyh4ck <butterflyhuangxx@gmail.com> reported a bug found by
syzkaller fuzzer with custom modifications in 5.12.0-rc3+ [1]:

 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x82/0x32c mm/kasan/report.c:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:416
 f2fs_test_bit fs/f2fs/f2fs.h:2572 [inline]
 current_nat_addr fs/f2fs/node.h:213 [inline]
 get_next_nat_page fs/f2fs/node.c:123 [inline]
 __flush_nat_entry_set fs/f2fs/node.c:2888 [inline]
 f2fs_flush_nat_entries+0x258e/0x2960 fs/f2fs/node.c:2991
 f2fs_write_checkpoint+0x1372/0x6a70 fs/f2fs/checkpoint.c:1640
 f2fs_issue_checkpoint+0x149/0x410 fs/f2fs/checkpoint.c:1807
 f2fs_sync_fs+0x20f/0x420 fs/f2fs/super.c:1454
 __sync_filesystem fs/sync.c:39 [inline]
 sync_filesystem fs/sync.c:67 [inline]
 sync_filesystem+0x1b5/0x260 fs/sync.c:48
 generic_shutdown_super+0x70/0x370 fs/super.c:448
 kill_block_super+0x97/0xf0 fs/super.c:1394

The root cause is, if nat entry in checkpoint journal area is corrupted,
e.g. nid of journalled nat entry exceeds max nid value, during checkpoint,
once it tries to flush nat journal to NAT area, get_next_nat_page() may
access out-of-bounds memory on nat_bitmap due to it uses wrong nid value
as bitmap offset.

[1] https://lore.kernel.org/lkml/CAFcO6XOMWdr8pObek6eN6-fs58KG9doRFadgJj-FnF-1x43s2g@mail.gmail.com/T/#u

Reported-and-tested-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2021-03-25 18:20:51 -07:00
..
acl.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
acl.h fs: make helpers idmap mount aware 2021-01-24 14:27:20 +01:00
checkpoint.c f2fs: update comments for explicit memory barrier 2021-03-12 13:16:42 -08:00
compress.c f2fs: add sysfs nodes to get runtime compression stat 2021-03-25 18:20:50 -07:00
compress.h f2fs: compress: fix compression chksum 2020-12-10 09:13:53 -08:00
data.c f2fs: fix to use per-inode maxbytes in f2fs_fiemap 2021-03-25 18:20:50 -07:00
debug.c f2fs: introduce checkpoint_merge mount option 2021-02-03 13:03:06 -08:00
dir.c f2fs-for-5.11-rc1 2020-12-17 11:18:00 -08:00
extent_cache.c f2fs: support 64-bits key in f2fs rb-tree node entry 2020-09-10 14:03:30 -07:00
f2fs.h f2fs: add sysfs nodes to get runtime compression stat 2021-03-25 18:20:50 -07:00
file.c f2fs: fix to align to section for fallocate() on pinned file 2021-03-23 10:41:12 -07:00
gc.c f2fs: do not use AT_SSR mode in FG_GC & high urgent BG_GC 2021-03-25 18:20:50 -07:00
gc.h f2fs: support age threshold based garbage collection 2020-09-11 11:11:15 -07:00
hash.c f2fs: Handle casefolding with Encryption 2020-12-02 22:00:21 -08:00
inline.c f2fs: fix a redundant call to f2fs_balance_fs if an error occurs 2021-03-12 13:16:44 -08:00
inode.c f2fs: compress: support chksum 2020-12-02 22:00:22 -08:00
Kconfig f2fs: compress: Allow modular (de)compression algorithms 2021-03-12 13:16:42 -08:00
Makefile f2fs: deprecate f2fs_trace_io 2021-01-27 15:20:07 -08:00
namei.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
node.c f2fs: fix to avoid out-of-bounds memory access 2021-03-25 18:20:51 -07:00
node.h f2fs: avoid race condition for shrinker count 2020-12-03 00:59:26 -08:00
recovery.c f2fs: change to use rwsem for cp_mutex 2020-12-02 22:00:21 -08:00
segment.c f2fs: do not use AT_SSR mode in FG_GC & high urgent BG_GC 2021-03-25 18:20:50 -07:00
segment.h f2fs: remove unused FORCE_FG_GC macro 2021-03-12 13:16:42 -08:00
shrinker.c f2fs: avoid race condition for shrinker count 2020-12-03 00:59:26 -08:00
super.c f2fs: don't start checkpoint thread in readonly mountpoint 2021-03-25 18:20:51 -07:00
sysfs.c f2fs: add sysfs nodes to get runtime compression stat 2021-03-25 18:20:50 -07:00
verity.c f2fs: fix error handling in f2fs_end_enable_verity() 2021-03-12 13:16:44 -08:00
xattr.c idmapped-mounts-v5.12 2021-02-23 13:39:45 -08:00
xattr.h f2fs: code cleanup by removing ifdef macro surrounding 2020-05-26 18:56:10 -07:00