f2fs: fix to avoid panic in f2fs_inplace_write_data()
As Jungyeon reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=203239
- Overview
When mounting the attached crafted image and running program, following errors are reported.
Additionally, it hangs on sync after running program.
The image is intentionally fuzzed from a normal f2fs image for testing.
Compile options for F2FS are as follows.
CONFIG_F2FS_FS=y
CONFIG_F2FS_STAT_FS=y
CONFIG_F2FS_FS_XATTR=y
CONFIG_F2FS_FS_POSIX_ACL=y
CONFIG_F2FS_CHECK_FS=y
- Reproduces
cc poc_15.c
./run.sh f2fs
sync
- Kernel messages
------------[ cut here ]------------
kernel BUG at fs/f2fs/segment.c:3162!
RIP: 0010:f2fs_inplace_write_data+0x12d/0x160
Call Trace:
f2fs_do_write_data_page+0x3c1/0x820
__write_data_page+0x156/0x720
f2fs_write_cache_pages+0x20d/0x460
f2fs_write_data_pages+0x1b4/0x300
do_writepages+0x15/0x60
__filemap_fdatawrite_range+0x7c/0xb0
file_write_and_wait_range+0x2c/0x80
f2fs_do_sync_file+0x102/0x810
do_fsync+0x33/0x60
__x64_sys_fsync+0xb/0x10
do_syscall_64+0x43/0xf0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The reason is f2fs_inplace_write_data() will trigger kernel panic due
to data block locates in node type segment.
To avoid panic, let's just return error code and set SBI_NEED_FSCK to
give a hint to fsck for latter repairing.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
1 file changed