From: Xin Long <lucien....@gmail.com>
Date: Sun, 2 Jun 2019 19:10:46 +0800
> In Jianlin's testing, netperf was broken with 'Connection reset by peer',
> as the cookie check failed in rt6_check() and ip6_dst_check() always
> returned NULL.
>
> It's caused by Commit 93531c674315 ("net/ipv6: separate handling of FIB
> entries from dst based routes"), where the cookie can be got only when
> 'c1'(see below) for setting dst_cookie whereas rt6_check() is called
> when !'c1' for checking dst_cookie, as we can see in ip6_dst_check().
>
> Since in ip6_dst_check() both rt6_dst_from_check() (c1) and rt6_check()
> (!c1) will check the 'from' cookie, this patch is to remove the c1 check
> in rt6_get_cookie(), so that the dst_cookie can always be set properly.
>
> c1:
> (rt->rt6i_flags & RTF_PCPU || unlikely(!list_empty(&rt->rt6i_uncached)))
>
> Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst
> based routes")
> Reported-by: Jianlin Shi <ji...@redhat.com>
> Signed-off-by: Xin Long <lucien....@gmail.com>
Applied and queued up for -stable.
