Patch "net/ipv6: Fix CALIPSO causing GPF with datagram support" has been added to the 4.11-stable tree

This is a note to let you know that I've just added the patch titled

net/ipv6: Fix CALIPSO causing GPF with datagram support

to the 4.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
net-ipv6-fix-calipso-causing-gpf-with-datagram-support.patch
and it can be found in the queue-4.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Richard Haines <[email protected]>
Date: Mon, 5 Jun 2017 16:44:40 +0100
Subject: net/ipv6: Fix CALIPSO causing GPF with datagram support

From: Richard Haines <[email protected]>

[ Upstream commit e3ebdb20fddacded2740a333ff66781e0d28b05c ]

When using CALIPSO with IPPROTO_UDP it is possible to trigger a GPF as the IP header may have moved.

Also update the payload length after adding the CALIPSO option.

---
 net/ipv6/calipso.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -1319,7 +1319,7 @@ static int calipso_skbuff_setattr(struct
 	struct ipv6hdr *ip6_hdr;
 	struct ipv6_opt_hdr *hop;
 	unsigned char buf[CALIPSO_MAX_BUFFER];
-	int len_delta, new_end, pad;
+	int len_delta, new_end, pad, payload;
 	unsigned int start, end;
 
 	ip6_hdr = ipv6_hdr(skb);

@@ -1346,6 +1346,8 @@ static int calipso_skbuff_setattr(struct
 	if (ret_val < 0)
 		return ret_val;
 
+	ip6_hdr = ipv6_hdr(skb); /* Reset as skb_cow() may have moved it */
+
 	if (len_delta) {
 		if (len_delta > 0)
 			skb_push(skb, len_delta);

@@ -1355,6 +1357,8 @@ static int calipso_skbuff_setattr(struct
 			sizeof(*ip6_hdr) + start);
 		skb_reset_network_header(skb);
 		ip6_hdr = ipv6_hdr(skb);
+		payload = ntohs(ip6_hdr->payload_len);
+		ip6_hdr->payload_len = htons(payload + len_delta);
 	}
 
 	hop = (struct ipv6_opt_hdr *)(ip6_hdr + 1);

Patches currently in stable-queue which might be from [email protected] are

queue-4.11/net-ipv6-fix-calipso-causing-gpf-with-datagram-support.patch