[ICMP]: Fix icmp_errors_use_inbound_ifaddr sysctl (6e1d9103) · Commits · 戴 / test

Currently when icmp_errors_use_inbound_ifaddr is set and an ICMP error is sent after the packet passed through ip_output(), an address from the outgoing interface is chosen as ICMP source address since skb->dev doesn't point to the incoming interface anymore. Fix this by doing an interface lookup on rt->dst.iif and using that device. Signed-off-by:

Patrick McHardy <kaber@trash.net> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/ipv4/icmp.c

+9 −6

Original line number	Diff line number	Diff line
		@@ -514,12 +514,15 @@ void icmp_send(struct sk_buff *skb_in, int type, int code, __be32 info)

		saddr = iph->daddr;
		if (!(rt->rt_flags & RTCF_LOCAL)) {
		/* This is broken, skb_in->dev points to the outgoing device
		* after the packet passes through ip_output().
		*/
		if (skb_in->dev && sysctl_icmp_errors_use_inbound_ifaddr)
		saddr = inet_select_addr(skb_in->dev, 0, RT_SCOPE_LINK);
		else
		struct net_device *dev = NULL;

		if (rt->fl.iif && sysctl_icmp_errors_use_inbound_ifaddr)
		dev = dev_get_by_index(rt->fl.iif);

		if (dev) {
		saddr = inet_select_addr(dev, 0, RT_SCOPE_LINK);
		dev_put(dev);
		} else
		saddr = 0;
		}

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