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

Nikolay Aleksandrov
2017-04-21T20:25:41Z

On 21/04/17 23:20, Cong Wang wrote:
> 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.
>

The patch was sent as a reply to the original report. :-)