From 2d44234bf9ed45ba1b91e4bcc929ab15f8b6a901 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sat, 8 Jun 2019 14:53:31 -0700 Subject: [PATCH] ipv6: Handle all fib6_nh in a nexthop in mtu updates Use nexthop_for_each_fib6_nh to call fib6_nh_mtu_change for each fib6_nh in a nexthop for rt6_mtu_change_route. For __ip6_rt_update_pmtu, we need to find the nexthop that correlates to the device and gateway in the rt6_info. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/ipv6/route.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 715356e00f58..f287375fd0b2 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2679,10 +2679,31 @@ static void __ip6_rt_update_pmtu(struct dst_entry *dst, const struct sock *sk, rcu_read_unlock(); return; } - res.nh = res.f6i->fib6_nh; res.fib6_flags = res.f6i->fib6_flags; res.fib6_type = res.f6i->fib6_type; + if (res.f6i->nh) { + struct fib6_nh_match_arg arg = { + .dev = dst->dev, + .gw = &rt6->rt6i_gateway, + }; + + nexthop_for_each_fib6_nh(res.f6i->nh, + fib6_nh_find_match, &arg); + + /* fib6_info uses a nexthop that does not have fib6_nh + * using the dst->dev + gw. Should be impossible. + */ + if (!arg.match) { + rcu_read_unlock(); + return; + } + + res.nh = arg.match; + } else { + res.nh = res.f6i->fib6_nh; + } + nrt6 = ip6_rt_cache_alloc(&res, daddr, saddr); if (nrt6) { rt6_do_update_pmtu(nrt6, mtu); @@ -4650,6 +4671,12 @@ static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg) return 0; arg->f6i = f6i; + if (f6i->nh) { + /* fib6_nh_mtu_change only returns 0, so this is safe */ + return nexthop_for_each_fib6_nh(f6i->nh, fib6_nh_mtu_change, + arg); + } + return fib6_nh_mtu_change(f6i->fib6_nh, arg); }