Commit 8a430e56 authored Apr 12, 2019 by Stephen Suryaputra Committed by Greg Kroah-Hartman Apr 27, 2019

ipv4: recompile ip options in ipv4_link_failure



[ Upstream commit ed0de45a1008991fdaa27a0152befcb74d126a8b ]

Recompile IP options since IPCB may not be valid anymore when
ipv4_link_failure is called from arp_error_report.

Refer to the commit 3da1ed7ac398 ("net: avoid use IPCB in cipso_v4_error")
and the commit before that (9ef6b42ad6fd) for a similar issue.

Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent b82df420

net/ipv4/route.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -1188,8 +1188,16 @@ static struct dst_entry ipv4_dst_check(struct dst_entry dst, u32 cookie)
		static void ipv4_link_failure(struct sk_buff *skb)
		{
		struct rtable *rt;
		struct ip_options opt;

		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
		/* Recompile ip options since IPCB may not be valid anymore.
		*/
		memset(&opt, 0, sizeof(opt));
		opt.optlen = ip_hdr(skb)->ihl*4 - sizeof(struct iphdr);
		if (__ip_options_compile(dev_net(skb->dev), &opt, skb, NULL))
		return;

		__icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0, &opt);

		rt = skb_rtable(skb);
		if (rt)