Re: [PATCH net] ipv6: no need to return rt->dst.error if it is not null entry.

[Hangbin Liu <liuhangbin@gmail.com>]

On Tue, Jul 25, 2017 at 10:49:05AM -0700, Cong Wang wrote:
> On Mon, Jul 24, 2017 at 5:08 PM, Hangbin Liu <liuhangbin@gmail.com> wrote:
> > But what we want in inet6_rtm_getroute() and rt6_dump_route() is to
> > get/dump the route info. So we should get the info even it's unreachable or
> > prohibit.
> 
> If you want to dump prohibit/blackhole entry, then you have to check
> for null_entry, and rt->dst.error check is still needed because we

I could not reproduce the NULL rt6i_idev issue after you route init fix, So
I think it's also safe to dump null_entry now. There is a v3 patch. After
the patch, we could dump unreachable route info like:

+ ip netns exec client ip -6 route get 2003::1
unreachable 2003::1 dev lo table unspec proto kernel metric 4294967295 error -101

> could return error on other normal entries too, IOW, your v2 is correct
> if dumping prohibit/blackhole is expected.

Would you hlep review the v3 patch? I prepare not touch the check in
function rt6_dump_route() now.

Thanks
Hangbin