path: root/net
diff options
authorSimon Horman <>2016-06-16 17:06:19 +0900
committerDavid S. Miller <>2016-06-16 17:10:30 -0700
commitd5d8760b78d0cfafe292f965f599988138b06a70 (patch)
tree683d59e8ac7443fc1d4a05e089c48ce62c34b949 /net
parenta547224dceed4645139f7eff72ff51adb9938bcb (diff)
sit: correct IP protocol used in ipip6_err
Since 32b8a8e59c9c ("sit: add IPv4 over IPv4 support") ipip6_err() may be called for packets whose IP protocol is IPPROTO_IPIP as well as those whose IP protocol is IPPROTO_IPV6. In the case of IPPROTO_IPIP packets the correct protocol value is not passed to ipv4_update_pmtu() or ipv4_redirect(). This patch resolves this problem by using the IP protocol of the packet rather than a hard-coded value. This appears to be consistent with the usage of the protocol of a packet by icmp_socket_deliver() the caller of ipip6_err(). I was able to exercise the redirect case by using a setup where an ICMP redirect was received for the destination of the encapsulated packet. However, it appears that although incorrect the protocol field is not used in this case and thus no problem manifests. On inspection it does not appear that a problem will manifest in the fragmentation needed/update pmtu case either. In short I believe this is a cosmetic fix. None the less, the use of IPPROTO_IPV6 seems wrong and confusing. Reviewed-by: Dinan Gunawardena <> Signed-off-by: Simon Horman <> Acked-by: YOSHIFUJI Hideaki <> Signed-off-by: David S. Miller <>
Diffstat (limited to 'net')
1 files changed, 2 insertions, 2 deletions
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index 0a5a255277e5..0619ac70836d 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -560,13 +560,13 @@ static int ipip6_err(struct sk_buff *skb, u32 info)
if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
ipv4_update_pmtu(skb, dev_net(skb->dev), info,
- t->, 0, IPPROTO_IPV6, 0);
+ t->, 0, iph->protocol, 0);
err = 0;
goto out;
if (type == ICMP_REDIRECT) {
ipv4_redirect(skb, dev_net(skb->dev), t->, 0,
+ iph->protocol, 0);
err = 0;
goto out;