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| author | Chao Yu <yuchao0@huawei.com> | 2021-05-07 18:10:38 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2021-05-14 11:22:08 -0700 |
| commit | cad83c968c2ebe97905f900326988ed37146c347 (patch) | |
| tree | 597783f54758209988cbd952cbce867d1ebac662 /fs/f2fs/f2fs.h | |
| parent | b763f3bedc2da2edf81bba550430847f561eae0e (diff) | |
| download | linux-cad83c968c2ebe97905f900326988ed37146c347.tar.bz2 | |
f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances
As syzbot reported, there is an use-after-free issue during f2fs recovery:
Use-after-free write at 0xffff88823bc16040 (in kfence-#10):
kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486
f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869
f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945
mount_bdev+0x26c/0x3a0 fs/super.c:1367
legacy_get_tree+0xea/0x180 fs/fs_context.c:592
vfs_get_tree+0x86/0x270 fs/super.c:1497
do_new_mount fs/namespace.c:2905 [inline]
path_mount+0x196f/0x2be0 fs/namespace.c:3235
do_mount fs/namespace.c:3248 [inline]
__do_sys_mount fs/namespace.c:3456 [inline]
__se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433
do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is multi f2fs filesystem instances can race on accessing
global fsync_entry_slab pointer, result in use-after-free issue of slab
cache, fixes to init/destroy this slab cache only once during module
init/destroy procedure to avoid this issue.
Reported-by: syzbot+9d90dad32dd9727ed084@syzkaller.appspotmail.com
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/f2fs.h')
| -rw-r--r-- | fs/f2fs/f2fs.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index f26a1c34102a..c0bead0df66a 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -3620,6 +3620,8 @@ void f2fs_destroy_garbage_collection_cache(void); */ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only); bool f2fs_space_for_roll_forward(struct f2fs_sb_info *sbi); +int __init f2fs_create_recovery_cache(void); +void f2fs_destroy_recovery_cache(void); /* * debug.c |