On Fri, May 5, 2023 at 4:51 PM syzbot <syzbot+8fb64a61fdd96b50f3b8@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > syzbot has bisected this issue to: > > commit d82dcd9e21b77d338dc4875f3d4111f0db314a7c > Author: Roberto Sassu <roberto.sassu@xxxxxxxxxx> > Date: Fri Mar 31 12:32:18 2023 +0000 > > reiserfs: Add security prefix to xattr name in reiserfs_security_write() > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14403182280000 > start commit: 3c4aa4434377 Merge tag 'ceph-for-6.4-rc1' of https://githu.. > git tree: upstream > final oops: https://syzkaller.appspot.com/x/report.txt?x=16403182280000 > console output: https://syzkaller.appspot.com/x/log.txt?x=12403182280000 > kernel config: https://syzkaller.appspot.com/x/.config?x=73a06f6ef2d5b492 > dashboard link: https://syzkaller.appspot.com/bug?extid=8fb64a61fdd96b50f3b8 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12442414280000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=176a7318280000 > > Reported-by: syzbot+8fb64a61fdd96b50f3b8@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: d82dcd9e21b7 ("reiserfs: Add security prefix to xattr name in reiserfs_security_write()") > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection I don't think Roberto's patch identified above is the actual root cause of this problem as reiserfs_xattr_set_handle() is called in reiserfs_security_write() both before and after the patch. However, due to some bad logic in reiserfs_security_write() which Roberto corrected, I'm thinking that it is possible this code is being exercised for the first time and syzbot is starting to trigger a locking issue in the reiserfs code ... ? -- paul-moore.com