From: Stephen Suryaputra Date: Fri, 12 Apr 2019 20:19:27 +0000 (-0400) Subject: ipv4: recompile ip options in ipv4_link_failure X-Git-Tag: v4.9.171~38 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ff71f99d5fb2daf54340e8b290d0bc4e6b4c1d38;p=thirdparty%2Fkernel%2Fstable.git 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 Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/ipv4/route.c b/net/ipv4/route.c index c42fb2330b454..956ce02c86dcc 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1171,8 +1171,16 @@ 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)