WARNING: kernel stack frame pointer at (ptrval) in syzkaller has bad value (ptrval)

From: syzbot
Date: Mon Apr 23 2018 - 06:10:09 EST


Hello,

syzbot hit the following crash on upstream commit
5ec83b22a2dd13180762c89698e4e2c2881a423c (Sun Apr 22 19:13:04 2018 +0000)
Merge tag '4.17-rc1-SMB3-CIFS' of git://git.samba.org/sfrench/cifs-2.6
syzbot dashboard link: https://syzkaller.appspot.com/bug?extid=e81cee75d9f3fe72ec33

C reproducer: https://syzkaller.appspot.com/x/repro.c?id=4545675937185792
syzkaller reproducer: https://syzkaller.appspot.com/x/repro.syz?id=6597511200374784
Raw console output: https://syzkaller.appspot.com/x/log.txt?id=4986591978192896
Kernel config: https://syzkaller.appspot.com/x/.config?id=1808800213120130118
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

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Reported-by: syzbot+e81cee75d9f3fe72ec33@xxxxxxxxxxxxxxxxxxxxxxxxx
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(ptrval): 000000000043fe19 (0x43fe19)
(ptrval): 0000000000000033 (0x33)
(ptrval): 0000000000000216 (0x216)
(ptrval): 00007ffd01ce4bd8 (0x7ffd01ce4bd8)
(ptrval): 000000000000002b (0x2b)
WARNING: kernel stack frame pointer at (ptrval) in syzkaller601944:4492 has bad value (ptrval)
WARNING: kernel stack regs at (ptrval) in syzkaller601944:4492 has bad 'bp' value (ptrval)


---
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