Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu. It leaded to that mtu lock doesn't really work when receiving the pkt of ICMPV6_PKT_TOOBIG.
This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4 did in __ip_rt_update_pmtu. Acked-by: Hannes Frederic Sowa <han...@stressinduktion.org> Signed-off-by: Xin Long <lucien....@gmail.com> --- net/ipv6/route.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 947ed1d..7403d90 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -1364,6 +1364,9 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk, if (rt6->rt6i_flags & RTF_LOCAL) return; + if (dst_metric_locked(dst, RTAX_MTU)) + return; + dst_confirm(dst); mtu = max_t(u32, mtu, IPV6_MIN_MTU); if (mtu >= dst_mtu(dst)) -- 2.1.0