syzbot has bisected this issue to:
commit 9df085f3c9a2d4658a9fe323d70c200aa00ede93
Author: Amir Goldstein <amir73il@xxxxxxxxx>
Date: Mon Sep 3 06:12:09 2018 +0000
ovl: relax requirement for non null uuid of lower fs
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=1711e75a680000
start commit: ac9a78681b92 Linux 6.4-rc1
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=1491e75a680000
console output: https://syzkaller.appspot.com/x/log.txt?x=1091e75a680000
kernel config: https://syzkaller.appspot.com/x/.config?x=8bc832f563d8bf38
dashboard link: https://syzkaller.appspot.com/bug?extid=7a278bf8bfa794494110
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1295e4b8280000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=140af20a280000
Reported-by: syzbot+7a278bf8bfa794494110@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 9df085f3c9a2 ("ovl: relax requirement for non null uuid of lower fs")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
