Re: WARNING in proc_register

[Dmitry Vyukov]

On Mon, Feb 5, 2018 at 8:41 PM, Alexey Dobriyan <adobriyan@xxxxxxxxx> wrote:
> On Mon, Feb 05, 2018 at 09:58:01AM -0800, syzbot wrote:
>> proc_dir_entry 'ipt_CLUSTERIP/172.20.0.170' already registered
>> WARNING: CPU: 1 PID: 4074 at fs/proc/generic.c:330
>
>>   proc_create_data+0xf8/0x180 fs/proc/generic.c:494
>>   clusterip_config_init net/ipv4/netfilter/ipt_CLUSTERIP.c:250 [inline]
>
> Dima, this warning is never about /proc but always about some other code
> registering duplicate /proc entry.
>
> I don't know how easily scriptable is mail sender but you want to look at
> the second line in the backtrace.

Hi Alexey,

This is now fixed with:
https://github.com/google/syzkaller/commit/645ce5da79c9654c314f0d12f4c11f2a94ec156b
In particular tests for this report:
https://github.com/google/syzkaller/blob/master/pkg/report/testdata/linux/report/181
https://github.com/google/syzkaller/blob/master/pkg/report/testdata/linux/guilty/30

Thanks for the suggestion.