When recalculating the outer ICMPv6 checksum for a reverse path NATv6 such as ICMPV6_TIME_EXCEED nf_nat_icmpv6_reply_translation() was accessing data beyond the headlen of the skb for non-linear skb. This resulted in incorrect ICMPv6 checksum as garbage data was used. Patch replaces csum_partial() with skb_checksum() which supports non-linear skbs similar to nf_nat_icmp_reply_translation() from ipv4. Signed-off-by: Dave Johnson <dave-kernel@xxxxxxxxxxxxxxx> --- diff -rup linux-4.9.23.orig/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c linux-4.9.23/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c --- linux-4.9.23.orig/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c 2017-04-18 01:12:30.000000000 -0400 +++ linux-4.9.23/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c 2017-04-24 09:00:31.476785772 -0400 @@ -235,7 +235,7 @@ int nf_nat_icmpv6_reply_translation(stru inside->icmp6.icmp6_cksum = csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, skb->len - hdrlen, IPPROTO_ICMPV6, - csum_partial(&inside->icmp6, + skb_checksum(skb, hdrlen, skb->len - hdrlen, 0)); } -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html