On Tue, Jan 16, 2018 at 7:07 PM, Marc Kleine-Budde [off-list ref] wrote:

On 01/16/2018 06:58 PM, syzbot wrote:

quoted

Hello,

syzkaller hit the following crash on
a8750ddca918032d6349adbf9a4b6555e7db20da
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers


IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+4386709c0c1284dca827@syzkaller.appspotmail.com
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details.
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device eql entered promiscuous mode
------------[ cut here ]------------
PF_CAN: dropped non conform CAN skbuf: dev type 65534, len 42, datalen 0
WARNING: CPU: 0 PID: 3650 at net/can/af_can.c:729 can_rcv+0x1c5/0x200
net/can/af_can.c:724
Kernel panic - not syncing: panic_on_warn set ...

Invalid packages generate a warning (WARN_ONCE()), and you have
panic_on_warn active. Should we better silently drop these CAN packages?

Hi,

pr_warn_once() will be more appropriate. It prints a single line.