diff options
| author | Chao Yu <chao@kernel.org> | 2022-04-27 12:51:40 +0300 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2022-05-06 20:18:12 +0300 |
| commit | 25f8236213a91efdf708b9d77e9e51b6fc3e141c (patch) | |
| tree | 29fc5e801a0f5756fd8ccd699aa2ddaf3ac5b4a5 /fs/f2fs | |
| parent | 4d17e6fe9293d57081ffdc11e1cf313e25e8fd9e (diff) | |
| download | linux-25f8236213a91efdf708b9d77e9e51b6fc3e141c.tar.xz | |
f2fs: fix to do sanity check on block address in f2fs_do_zero_range()
As Yanming reported in bugzilla:
https://bugzilla.kernel.org/show_bug.cgi?id=215894
I have encountered a bug in F2FS file system in kernel v5.17.
I have uploaded the system call sequence as case.c, and a fuzzed image can
be found in google net disk
The kernel should enable CONFIG_KASAN=y and CONFIG_KASAN_INLINE=y. You can
reproduce the bug by running the following commands:
kernel BUG at fs/f2fs/segment.c:2291!
Call Trace:
f2fs_invalidate_blocks+0x193/0x2d0
f2fs_fallocate+0x2593/0x4a70
vfs_fallocate+0x2a5/0xac0
ksys_fallocate+0x35/0x70
__x64_sys_fallocate+0x8e/0xf0
do_syscall_64+0x3b/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
The root cause is, after image was fuzzed, block mapping info in inode
will be inconsistent with SIT table, so in f2fs_fallocate(), it will cause
panic when updating SIT with invalid blkaddr.
Let's fix the issue by adding sanity check on block address before updating
SIT table with it.
Cc: stable@vger.kernel.org
Reported-by: Ming Yan <yanming@tju.edu.cn>
Signed-off-by: Chao Yu <chao.yu@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs')
| -rw-r--r-- | fs/f2fs/file.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index eae2e7908072..e4cf8b7b23aa 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1438,11 +1438,19 @@ static int f2fs_do_zero_range(struct dnode_of_data *dn, pgoff_t start, ret = -ENOSPC; break; } - if (dn->data_blkaddr != NEW_ADDR) { - f2fs_invalidate_blocks(sbi, dn->data_blkaddr); - dn->data_blkaddr = NEW_ADDR; - f2fs_set_data_blkaddr(dn); + + if (dn->data_blkaddr == NEW_ADDR) + continue; + + if (!f2fs_is_valid_blkaddr(sbi, dn->data_blkaddr, + DATA_GENERIC_ENHANCE)) { + ret = -EFSCORRUPTED; + break; } + + f2fs_invalidate_blocks(sbi, dn->data_blkaddr); + dn->data_blkaddr = NEW_ADDR; + f2fs_set_data_blkaddr(dn); } f2fs_update_extent_cache_range(dn, start, 0, index - start); |