diff options
| author | Edward Adam Davis <eadavis@qq.com> | 2025-11-27 11:26:40 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-12-10 16:07:41 -0800 |
| commit | 4ac577ae741e745ecfb64c5a9c7f52fc36aca022 (patch) | |
| tree | 49fe96184084c4536b12865b34b495b8a417faca | |
| parent | b2135d1cb0e368dcdb8631ed2f232caefbd7711f (diff) | |
ocfs2: check tl_used after reading it from trancate log inode
The fuzz image has a truncate log inode whose tl_used is bigger than
tl_count so it triggers the BUG in ocfs2_truncate_log_needs_flush() [1].
As what the check in ocfs2_truncate_log_needs_flush() does, just do same
check into ocfs2_get_truncate_log_info() when truncate log inode is
reading in so we can bail out earlier.
[1]
(syz.0.17,5491,0):ocfs2_truncate_log_needs_flush:5830 ERROR: bug expression: le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count)
kernel BUG at fs/ocfs2/alloc.c:5830!
RIP: 0010:ocfs2_truncate_log_needs_flush fs/ocfs2/alloc.c:5827 [inline]
Call Trace:
ocfs2_commit_truncate+0xb64/0x21d0 fs/ocfs2/alloc.c:7372
ocfs2_truncate_file+0xca2/0x1420 fs/ocfs2/file.c:509
ocfs2_setattr+0x1520/0x1b40 fs/ocfs2/file.c:1212
notify_change+0xc1a/0xf40 fs/attr.c:546
do_truncate+0x1a4/0x220 fs/open.c:68
Link: https://lkml.kernel.org/r/tencent_B24B1C1BE225DCBA44BB6933AB9E1B1B0708@qq.com
Reported-by: syzbot+f82afc4d4e74d0ef7a89@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=f82afc4d4e74d0ef7a89
Tested-by: syzbot+f82afc4d4e74d0ef7a89@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Changwei Ge <gechangwei@live.cn>
Cc: Jun Piao <piaojun@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | fs/ocfs2/alloc.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c index 162711cc5b20..ba26d21344bd 100644 --- a/fs/ocfs2/alloc.c +++ b/fs/ocfs2/alloc.c @@ -6164,7 +6164,7 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb, struct buffer_head *bh = NULL; struct ocfs2_dinode *di; struct ocfs2_truncate_log *tl; - unsigned int tl_count; + unsigned int tl_count, tl_used; inode = ocfs2_get_system_file_inode(osb, TRUNCATE_LOG_SYSTEM_INODE, @@ -6185,8 +6185,10 @@ static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb, di = (struct ocfs2_dinode *)bh->b_data; tl = &di->id2.i_dealloc; tl_count = le16_to_cpu(tl->tl_count); + tl_used = le16_to_cpu(tl->tl_used); if (unlikely(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) || - tl_count == 0)) { + tl_count == 0 || + tl_used > tl_count)) { status = -EFSCORRUPTED; iput(inode); brelse(bh); |