linux-kernel - [PATCH] ocfs2: prevent release journal inode after journal shutdown

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <tencent_5E787A6C242FE96CC89454E856EC52CEC40A@qq.com>
Date: Tue, 19 Aug 2025 21:32:48 +0800
From: Edward Adam Davis <eadavis@...com>
To: syzbot+47d8cb2f2cc1517e515a@...kaller.appspotmail.com
Cc: jlbec@...lplan.org,
	joseph.qi@...ux.alibaba.com,
	linux-kernel@...r.kernel.org,
	mark@...heh.com,
	ocfs2-devel@...ts.linux.dev,
	syzkaller-bugs@...glegroups.com
Subject: [PATCH] ocfs2: prevent release journal inode after journal shutdown

Before calling ocfs2_delete_osb(), ocfs2_journal_shutdown() has already
been executed in ocfs2_dismount_volume(), so osb->journal must be NULL.
Therefore, the following calltrace will inevitably fail when it reaches
jbd2_journal_release_jbd_inode().

ocfs2_dismount_volume()->
  ocfs2_delete_osb()->
    ocfs2_free_slot_info()->
      __ocfs2_free_slot_info()->
        evict()->
          ocfs2_evict_inode()->
            ocfs2_clear_inode()->
	      jbd2_journal_release_jbd_inode(osb->journal->j_journal,

Adding osb->journal checks will prevent UAF during the above execution path.

Reported-by: syzbot+47d8cb2f2cc1517e515a@...kaller.appspotmail.com
Closest: https://syzkaller.appspot.com/bug?extid=47d8cb2f2cc1517e515a
Tested-by: syzbot+47d8cb2f2cc1517e515a@...kaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@...com>
---
 fs/ocfs2/inode.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 14bf440ea4df..6c4f78f473fb 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -1281,6 +1281,9 @@ static void ocfs2_clear_inode(struct inode *inode)
 	 * the journal is flushed before journal shutdown. Thus it is safe to
 	 * have inodes get cleaned up after journal shutdown.
 	 */
+	if (!osb->journal)
+		return;
+
 	jbd2_journal_release_jbd_inode(osb->journal->j_journal,
 				       &oi->ip_jinode);
 }
-- 
2.43.0