6.12-stable review patch. If anyone has any objections, please let me know.
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From: Edward Adam Davis eadavis@qq.com
commit f46e8ef8bb7b452584f2e75337b619ac51a7cadf upstream.
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 null-ptr-deref during the above execution path.
Link: https://lkml.kernel.org/r/tencent_357489BEAEE4AED74CBD67D246DBD2C4C606@qq.co... Fixes: da5e7c87827e ("ocfs2: cleanup journal init and shutdown") Signed-off-by: Edward Adam Davis eadavis@qq.com Reported-by: syzbot+47d8cb2f2cc1517e515a@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=47d8cb2f2cc1517e515a Tested-by: syzbot+47d8cb2f2cc1517e515a@syzkaller.appspotmail.com Reviewed-by: Mark Tinguely mark.tinguely@oracle.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 Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ocfs2/inode.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -1205,6 +1205,9 @@ static void ocfs2_clear_inode(struct ino * 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); }