kernel panic: stack is corrupted in udp4_lib_lookup2

From: syzbot
Date: Thu Jan 03 2019 - 08:07:10 EST


syzbot found the following crash on:

HEAD commit: 195303136f19 Merge tag 'kconfig-v4.21-2' of git://git.kern..
git tree: upstream
console output:
kernel config:
dashboard link:
compiler: gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4ad25edc7a33e4ab91e0@xxxxxxxxxxxxxxxxxxxxxxxxx

protocol 88fb is buggy, dev hsr_slave_1
protocol 88fb is buggy, dev hsr_slave_0
protocol 88fb is buggy, dev hsr_slave_1
FAT-fs (loop0): invalid media value (0x00)
FAT-fs (loop0): Can't find a valid FAT filesystem
Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: udp4_lib_lookup2+0x7ea/0x7f0 net/ipv4/udp.c:455
CPU: 1 PID: 17960 Comm: syz-executor2 Not tainted 4.20.0+ #176
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
Kernel Offset: disabled
Rebooting in 86400 seconds..

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