[syzbot] [btrfs?] VFS: Busy inodes after unmount (use-after-free)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    edb2f0dc90f2 Merge branch 'for-next/core' into for-kernelci
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=1484d22e480000
kernel config:  https://syzkaller.appspot.com/x/.config?x=a1c301efa2b11613
dashboard link: https://syzkaller.appspot.com/bug?extid=0af00f6a2cba2058b5db
compiler:       Debian clang version 13.0.1-++20220126092033+75e33f71c2da-1~exp1~20220126212112.63, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: arm64
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=15e20341480000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=154fa4f1480000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/ca1677dc6969/disk-edb2f0dc.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/22527595a2dd/vmlinux-edb2f0dc.xz
kernel image: https://storage.googleapis.com/syzbot-assets/45308e5f6962/Image-edb2f0dc.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/6105a892b6d5/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0af00f6a2cba2058b5db@xxxxxxxxxxxxxxxxxxxxxxxxx

VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds.  Have a nice day...
VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds.  Have a nice day...


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches