On Wed, 6 Jan 2021 09:55:09 -0700 David Ahern wrote:
> On 1/5/21 5:22 PM, Sean Tranchetti wrote:
> > From: Sean Tranchetti <stran...@codeaurora.org>
> >
> > Route removal is handled by two code paths. The main removal path is via
> > fib6_del_route() which will handle purging any PMTU exceptions from the
> > cache, removing all per-cpu copies of the DST entry used by the route, and
> > releasing the fib6_info struct.
> >
> > The second removal location is during fib6_add_rt2node() during a route
> > replacement operation. This path also calls fib6_purge_rt() to handle
> > cleaning up the per-cpu copies of the DST entries and releasing the
> > fib6_info associated with the older route, but it does not flush any PMTU
> > exceptions that the older route had. Since the older route is removed from
> > the tree during the replacement, we lose any way of accessing it again.
> >
> > As these lingering DSTs and the fib6_info struct are holding references to
> > the underlying netdevice struct as well, unregistering that device from the
> > kernel can never complete.
>
> I think the right fixes tag is:
>
> Fixes: 2b760fcf5cfb3 ("ipv6: hook up exception table to store dst cache")
>
> cc'ed author of that patch.
>
> > Signed-off-by: Sean Tranchetti <stran...@codeaurora.org>
>
> Reviewed-by: David Ahern <dsah...@kernel.org>
Applied, thanks!
