diff --git a/net/ipv6/ila/ila_common.c b/net/ipv6/ila/ila_common.c index b8d43ed4689d..ca54a227fc2f 100644 --- a/net/ipv6/ila/ila_common.c +++ b/net/ipv6/ila/ila_common.c @@ -84,6 +84,7 @@ static void ila_csum_adjust_transport(struct sk_buff *skb, struct tcphdr *th = (struct tcphdr *) (skb_network_header(skb) + nhoff); + ip6h = ipv6_hdr(skb); diff = get_csum_diff(ip6h, p); inet_proto_csum_replace_by_diff(&th->check, skb, diff, true, true); @@ -95,6 +96,7 @@ static void ila_csum_adjust_transport(struct sk_buff *skb, (skb_network_header(skb) + nhoff); if (uh->check || skb->ip_summed == CHECKSUM_PARTIAL) { + ip6h = ipv6_hdr(skb); diff = get_csum_diff(ip6h, p); inet_proto_csum_replace_by_diff(&uh->check, skb, diff, true, true); @@ -109,6 +111,7 @@ static void ila_csum_adjust_transport(struct sk_buff *skb, struct icmp6hdr *ih = (struct icmp6hdr *) (skb_network_header(skb) + nhoff); + ip6h = ipv6_hdr(skb); diff = get_csum_diff(ip6h, p); inet_proto_csum_replace_by_diff(&ih->icmp6_cksum, skb, diff, true, true); @@ -126,6 +129,15 @@ void ila_update_ipv6_locator(struct sk_buff *skb, struct ila_params *p, switch (p->csum_mode) { case ILA_CSUM_ADJUST_TRANSPORT: ila_csum_adjust_transport(skb, p); + /* + * ila_csum_adjust_transport() calls pskb_may_pull(), which can + * reallocate the skb head and leave ip6h (and the iaddr derived + * from it) dangling; reload both before the write below. The + * other csum modes do not pull, so their cached pointers stay + * valid. + */ + ip6h = ipv6_hdr(skb); + iaddr = ila_a2i(&ip6h->daddr); break; case ILA_CSUM_NEUTRAL_MAP: if (sir2ila) {