net: Fix IPv6 PMTU disc. w/ asymmetric routes (ae878ae2) · Commits · e / devices / android_kernel_sony_msm8994

net/ipv6/route.c

+24 −4

Original line number	Diff line number	Diff line
		@@ -1556,14 +1556,13 @@ out:
		* i.e. Path MTU discovery
		*/

		void rt6_pmtu_discovery(struct in6_addr daddr, struct in6_addr saddr,
		struct net_device *dev, u32 pmtu)
		static void rt6_do_pmtu_disc(struct in6_addr daddr, struct in6_addr saddr,
		struct net *net, u32 pmtu, int ifindex)
		{
		struct rt6_info rt, nrt;
		struct net *net = dev_net(dev);
		int allfrag = 0;

		rt = rt6_lookup(net, daddr, saddr, dev->ifindex, 0);
		rt = rt6_lookup(net, daddr, saddr, ifindex, 0);
		if (rt == NULL)
		return;

		@@ -1631,6 +1630,27 @@ out:
		dst_release(&rt->dst);
		}

		void rt6_pmtu_discovery(struct in6_addr daddr, struct in6_addr saddr,
		struct net_device *dev, u32 pmtu)
		{
		struct net *net = dev_net(dev);

		/*
		* RFC 1981 states that a node "MUST reduce the size of the packets it
		* is sending along the path" that caused the Packet Too Big message.
		* Since it's not possible in the general case to determine which
		* interface was used to send the original packet, we update the MTU
		* on the interface that will be used to send future packets. We also
		* update the MTU on the interface that received the Packet Too Big in
		* case the original packet was forced out that interface with
		* SO_BINDTODEVICE or similar. This is the next best thing to the
		* correct behaviour, which would be to update the MTU on all
		* interfaces.
		*/
		rt6_do_pmtu_disc(daddr, saddr, net, pmtu, 0);
		rt6_do_pmtu_disc(daddr, saddr, net, pmtu, dev->ifindex);
		}

		/*
		* Misc support functions
		*/