[Bridge] Use-after-free in br_multicast_rcv

[Martin Weinelt]

Hi Nik,

On 7/2/19 12:37 AM, Nikolay Aleksandrov wrote:
> On 7/2/19 1:17 AM, Martin Weinelt wrote:
>> Hi again,
>>
>> On 7/1/19 7:37 PM, Nikolay Aleksandrov wrote:
>>> I see, thanks for clarifying this. So on the KASAN could you please try the attached patch ?
>>> Also could you please run the br_multicast_rcv+xxx addresses through
>>> linux/scripts/faddr2line for your kernel/bridge:
>>> usage: faddr2line [--list] <object file> <func+offset> <func+offset>...
>>>
>>> Thanks,
>>>  Nik
>>>
>>
>> back with a new report. This is 5.2.0-rc7 + your patch.
>>
>> Best,
>>   Martin
>>
> 
> Thanks! Aaargh.. I made a stupid mistake hurrying to send the patch, apologies.
> Here's the fixed version, please give it a go. This report is because
> of my change, not because of the previous bug that should've been fixed.
> 

I applied your latest patch against 5.2.0-rc7 and it seems to have fixed the issue as,
after 6 hours of uptime, the KASAN report isn't coming up anymore.

Also there are currently no kmemleak results coming up on 5.2.0-rc7, so I'll be
looking at the v4.19.x series next.

Thank you!

Best
  Martin