Re: [PATCH net] ip6mr: fix notification device destruction

From: Nikolay Aleksandrov
Date: Fri Apr 21 2017 - 15:50:45 EST


On 21/04/17 22:36, David Miller wrote:
> From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
> Date: Fri, 21 Apr 2017 21:30:42 +0300
>
>> On 21/04/17 20:42, Nikolay Aleksandrov wrote:
>>> Andrey Konovalov reported a BUG caused by the ip6mr code which is caused
>>> because we call unregister_netdevice_many for a device that is already
>>> being destroyed. In IPv4's ipmr that has been resolved by two commits
>>> long time ago by introducing the "notify" parameter to the delete
>>> function and avoiding the unregister when called from a notifier, so
>>> let's do the same for ip6mr.
> ...
>> +CC LKML and Linus
>
> Applied, thanks Nikolay and thanks Andrey for the report and testing.
>
> Nikolay, how far does this bug go back?
>

Good question, AFAICS since ip6mr exists because it was copied from ipmr:
commit 7bc570c8b4f7
Author: YOSHIFUJI Hideaki <yoshfuji@xxxxxxxxxxxxxx>
Date: Thu Apr 3 09:22:53 2008 +0900

[IPV6] MROUTE: Support multicast forwarding.