Re: [Patch net] ip6mr: avoid double unregister of pim6reg device

Cong Wang
2017-04-21T20:20:54Z

On Fri, Apr 21, 2017 at 12:34 PM, Nikolay Aleksandrov
<nikolay@cumulusnetworks.com> wrote:
> On 21/04/17 22:27, Cong Wang wrote:
>> If we unregister the pim6reg device via default_device_exit_batch(),
>> we will receive a notification and ip6mr_device_event() will
>> unregister it again. This causes a kernel BUG at net/core/dev.c:6813.
>>
>> Like commit 7dc00c82cbb0 ("ipv4: Fix ipmr unregister device oops")
>> we should avoid double-unregister in netdevice notifier.
>>
>> Reported-by: Andrey Konovalov <andreyknvl@google.com>
>> Cc: Linus Torvalds <torvalds@linux-foundation.org>
>> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
>> ---
>> net/ipv6/ip6mr.c | 11 ++++++-----
>> 1 file changed, 6 insertions(+), 5 deletions(-)
>>
>
> Cong,
> Please read the full thread, I've already provided a fix which is similar.
> https://patchwork.ozlabs.org/patch/753531/

You beat me on that. ;) You should leave a reply to Andrey's report
otherwise people could miss it.