diff options
| author | Edward Adam Davis <eadavis@qq.com> | 2025-12-28 11:53:25 +0800 |
|---|---|---|
| committer | Sasha Levin <sashal@kernel.org> | 2026-03-04 07:20:02 -0500 |
| commit | 6d93239b4fc479f7c0a412dd196ec0ca2672d14a (patch) | |
| tree | d258813fa657291bfb607c3b1c309ad294dfd768 /fs | |
| parent | 84083e178b57fd810761f6a609921163549ec436 (diff) | |
fs/ntfs3: prevent infinite loops caused by the next valid being the same
[ Upstream commit 27b75ca4e51e3e4554dc85dbf1a0246c66106fd3 ]
When processing valid within the range [valid : pos), if valid cannot
be retrieved correctly, for example, if the retrieved valid value is
always the same, this can trigger a potential infinite loop, similar
to the hung problem reported by syzbot [1].
Adding a check for the valid value within the loop body, and terminating
the loop and returning -EINVAL if the value is the same as the current
value, can prevent this.
[1]
INFO: task syz.4.21:6056 blocked for more than 143 seconds.
Call Trace:
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock include/linux/fs.h:1027 [inline]
ntfs_file_write_iter+0xe6/0x870 fs/ntfs3/file.c:1284
Fixes: 4342306f0f0d ("fs/ntfs3: Add file operations and implementation")
Reported-by: syzbot+bcf9e1868c1a0c7e04f1@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=bcf9e1868c1a0c7e04f1
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ntfs3/file.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/ntfs3/file.c b/fs/ntfs3/file.c index 6d9c1dfe9b1b..f2d1df2c988a 100644 --- a/fs/ntfs3/file.c +++ b/fs/ntfs3/file.c @@ -870,8 +870,12 @@ static ssize_t ntfs_compress_write(struct kiocb *iocb, struct iov_iter *from) goto out; if (lcn == SPARSE_LCN) { - ni->i_valid = valid = - frame_vbo + ((u64)clen << sbi->cluster_bits); + valid = frame_vbo + ((u64)clen << sbi->cluster_bits); + if (ni->i_valid == valid) { + err = -EINVAL; + goto out; + } + ni->i_valid = valid; continue; } |