Patch "ipv6: Check ip6_find_1stfragopt() return value properly." has been added to the 4.9-stable tree

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

ipv6: Check ip6_find_1stfragopt() return value properly.

to the 4.9-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:
ipv6-check-ip6_find_1stfragopt-return-value-properly.patch
and it can be found in the queue-4.9 subdirectory.

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

From: "David S. Miller" <[email protected]>
Date: Wed, 17 May 2017 22:54:11 -0400
Subject: ipv6: Check ip6_find_1stfragopt() return value properly.

From: "David S. Miller" <[email protected]>

[ Upstream commit 7dd7eb9513bd02184d45f000ab69d78cb1fa1531 ]

Do not use unsigned variables to see if it returns a negative error or not.

---
 net/ipv6/ip6_offload.c |    9 ++++-----
 net/ipv6/ip6_output.c  |    7 +++----
 net/ipv6/udp_offload.c |    8 +++++---
 3 files changed, 12 insertions(+), 12 deletions(-)

@@ -63,7 +63,6 @@ static struct sk_buff *ipv6_gso_segment(
 	const struct net_offload *ops;
 	int proto;
 	struct frag_hdr *fptr;
-	unsigned int unfrag_ip6hlen;
 	unsigned int payload_len;
 	u8 *prevhdr;
 	int offset = 0;

@@ -116,10 +115,10 @@ static struct sk_buff *ipv6_gso_segment(
 		skb->network_header = (u8 *)ipv6h - skb->head;
 
 		if (udpfrag) {
-			unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
-			if (unfrag_ip6hlen < 0)
-				return ERR_PTR(unfrag_ip6hlen);
-			fptr = (struct frag_hdr *)((u8 *)ipv6h + unfrag_ip6hlen);
+			int err = ip6_find_1stfragopt(skb, &prevhdr);
+			if (err < 0)
+				return ERR_PTR(err);
+			fptr = (struct frag_hdr *)((u8 *)ipv6h + err);
 			fptr->frag_off = htons(offset);
 			if (skb->next)
 				fptr->frag_off |= htons(IP6_MF);

@@ -586,11 +586,10 @@ int ip6_fragment(struct net *net, struct
 	int ptr, offset = 0, err = 0;
 	u8 *prevhdr, nexthdr = 0;
 
-	hlen = ip6_find_1stfragopt(skb, &prevhdr);
-	if (hlen < 0) {
-		err = hlen;
+	err = ip6_find_1stfragopt(skb, &prevhdr);
+	if (err < 0)
 		goto fail;
-	}
+	hlen = err;
 	nexthdr = *prevhdr;
 
 	mtu = ip6_skb_dst_mtu(skb);

@@ -29,6 +29,7 @@ static struct sk_buff *udp6_ufo_fragment
 	u8 frag_hdr_sz = sizeof(struct frag_hdr);
 	__wsum csum;
 	int tnl_hlen;
+	int err;
 
 	mss = skb_shinfo(skb)->gso_size;
 	if (unlikely(skb->len <= mss))

@@ -90,9 +91,10 @@ static struct sk_buff *udp6_ufo_fragment
 		/* Find the unfragmentable header and shift it left by frag_hdr_sz
 		 * bytes to insert fragment header.
 		 */
-		unfrag_ip6hlen = ip6_find_1stfragopt(skb, &prevhdr);
-		if (unfrag_ip6hlen < 0)
-			return ERR_PTR(unfrag_ip6hlen);
+		err = ip6_find_1stfragopt(skb, &prevhdr);
+		if (err < 0)
+			return ERR_PTR(err);
+		unfrag_ip6hlen = err;
 		nexthdr = *prevhdr;
 		*prevhdr = NEXTHDR_FRAGMENT;
 		unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) +

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

queue-4.9/ipv6-prevent-overrun-when-parsing-v6-header-options.patch queue-4.9/vlan-fix-tcp-checksum-offloads-in-q-in-q-vlans.patch queue-4.9/s390-qeth-unbreak-osm-and-osn-support.patch queue-4.9/ipv6-fix-out-of-bound-writes-in-__ip6_append_data.patch queue-4.9/bridge-netlink-check-vlan_default_pvid-range.patch queue-4.9/sctp-fix-src-address-selection-if-using-secondary-addresses-for-ipv6.patch queue-4.9/tcp-eliminate-negative-reordering-in-tcp_clean_rtx_queue.patch queue-4.9/dccp-tcp-do-not-inherit-mc_list-from-parent.patch queue-4.9/net-packet-fix-missing-net_device-reference-release.patch queue-4.9/qmi_wwan-add-another-lenovo-em74xx-device-id.patch queue-4.9/tcp-avoid-fragmenting-peculiar-skbs-in-sack.patch queue-4.9/driver-vrf-fix-one-possible-use-after-free-issue.patch queue-4.9/be2net-fix-offload-features-for-q-in-q-packets.patch queue-4.9/virtio-net-enable-tso-checksum-offloads-for-q-in-q-vlans.patch queue-4.9/s390-qeth-avoid-null-pointer-dereference-on-osn.patch queue-4.9/netem-fix-skb_orphan_partial.patch queue-4.9/bridge-start-hello_timer-when-enabling-kernel_stp-in-br_stp_start.patch queue-4.9/net-phy-marvell-limit-errata-to-88m1101.patch queue-4.9/net-fix-compile-error-in-skb_orphan_partial.patch queue-4.9/ipv6-dccp-do-not-inherit-ipv6_mc_list-from-parent.patch queue-4.9/bpf-arm64-fix-faulty-emission-of-map-access-in-tail-calls.patch queue-4.9/s390-qeth-handle-sysfs-error-during-initialization.patch queue-4.9/sctp-fix-icmp-processing-if-skb-is-non-linear.patch queue-4.9/ipv6-check-ip6_find_1stfragopt-return-value-properly.patch queue-4.9/bpf-add-bpf_clone_redirect-to-bpf_helper_changes_pkt_data.patch queue-4.9/s390-qeth-add-missing-hash-table-initializations.patch queue-4.9/sctp-do-not-inherit-ipv6_-mc-ac-fl-_list-from-parent.patch queue-4.9/net-improve-handling-of-failures-on-link-and-route-dumps.patch queue-4.9/bonding-fix-accounting-of-active-ports-in-3ad.patch queue-4.9/ipv4-add-reference-counting-to-metrics.patch queue-4.9/tcp-avoid-fastopen-api-to-be-used-on-af_unspec.patch