WARNING: lock held when returning to user space! (3)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    903b77c63167 Merge tag 'linux-kselftest-4.21-rc1' of git:/..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1424673b400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=53a2f2aa0b1f7606
dashboard link: https://syzkaller.appspot.com/bug?extid=42e36e1ae3de3f22a7ed
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1453eabf400000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=14a492bf400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+42e36e1ae3de3f22a7ed@xxxxxxxxxxxxxxxxxxxxxxxxx

RBP: 00000000006cf018 R08: 0000000000000001 R09: 0000000000000032
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005
R13: ffffffffffffffff R14: 0000000000000000 R15: 0000000000000000

================================================
WARNING: lock held when returning to user space!
4.20.0+ #395 Not tainted
------------------------------------------------
syz-executor520/8085 is leaving the kernel with locks still held!


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