Patch "vxlan: don't allow overwrite of config src addr" has been added to the 4.9-stable tree

Patch "vxlan: don't allow overwrite of config src addr" has been added to the 4.9-stable tree

[gregkh]

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

    vxlan: don't allow overwrite of config src addr

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:
     vxlan-don-t-allow-overwrite-of-config-src-addr.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 <stable@vger.kernel.org> know about it.


>From foo@baz Sat Mar 18 22:03:25 CST 2017
From: Brian Russell <brussell@brocade.com>
Date: Fri, 24 Feb 2017 17:47:11 +0000
Subject: vxlan: don't allow overwrite of config src addr

From: Brian Russell <brussell@brocade.com>


[ Upstream commit 1158632b5a2dcce0786c1b1b99654e81cc867981 ]

When using IPv6 transport and a default dst, a pointer to the configured
source address is passed into the route lookup. If no source address is
configured, then the value is overwritten.

IPv6 route lookup ignores egress ifindex match if the source address is set,
so if egress ifindex match is desired, the source address must be passed
as any. The overwrite breaks this for subsequent lookups.

Avoid this by copying the configured address to an existing stack variable
and pass a pointer to that instead.

Fixes: 272d96a5ab10 ("net: vxlan: lwt: Use source ip address during route lookup.")

Signed-off-by: Brian Russell <brussell@brocade.com>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/net/vxlan.c |   12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1942,7 +1942,6 @@ static void vxlan_xmit_one(struct sk_buf
 	const struct iphdr *old_iph;
 	union vxlan_addr *dst;
 	union vxlan_addr remote_ip, local_ip;
-	union vxlan_addr *src;
 	struct vxlan_metadata _md;
 	struct vxlan_metadata *md = &_md;
 	__be16 src_port = 0, dst_port;
@@ -1960,7 +1959,7 @@ static void vxlan_xmit_one(struct sk_buf
 		dst_port = rdst->remote_port ? rdst->remote_port : vxlan->cfg.dst_port;
 		vni = rdst->remote_vni;
 		dst = &rdst->remote_ip;
-		src = &vxlan->cfg.saddr;
+		local_ip = vxlan->cfg.saddr;
 		dst_cache = &rdst->dst_cache;
 	} else {
 		if (!info) {
@@ -1979,7 +1978,6 @@ static void vxlan_xmit_one(struct sk_buf
 			local_ip.sin6.sin6_addr = info->key.u.ipv6.src;
 		}
 		dst = &remote_ip;
-		src = &local_ip;
 		dst_cache = &info->dst_cache;
 	}
 
@@ -2028,7 +2026,7 @@ static void vxlan_xmit_one(struct sk_buf
 		rt = vxlan_get_route(vxlan, skb,
 				     rdst ? rdst->remote_ifindex : 0, tos,
 				     dst->sin.sin_addr.s_addr,
-				     &src->sin.sin_addr.s_addr,
+				     &local_ip.sin.sin_addr.s_addr,
 				     dst_cache, info);
 		if (IS_ERR(rt)) {
 			netdev_dbg(dev, "no route to %pI4\n",
@@ -2071,7 +2069,7 @@ static void vxlan_xmit_one(struct sk_buf
 		if (err < 0)
 			goto xmit_tx_error;
 
-		udp_tunnel_xmit_skb(rt, sk, skb, src->sin.sin_addr.s_addr,
+		udp_tunnel_xmit_skb(rt, sk, skb, local_ip.sin.sin_addr.s_addr,
 				    dst->sin.sin_addr.s_addr, tos, ttl, df,
 				    src_port, dst_port, xnet, !udp_sum);
 #if IS_ENABLED(CONFIG_IPV6)
@@ -2087,7 +2085,7 @@ static void vxlan_xmit_one(struct sk_buf
 		ndst = vxlan6_get_route(vxlan, skb,
 					rdst ? rdst->remote_ifindex : 0, tos,
 					label, &dst->sin6.sin6_addr,
-					&src->sin6.sin6_addr,
+					&local_ip.sin6.sin6_addr,
 					dst_cache, info);
 		if (IS_ERR(ndst)) {
 			netdev_dbg(dev, "no route to %pI6\n",
@@ -2134,7 +2132,7 @@ static void vxlan_xmit_one(struct sk_buf
 			return;
 		}
 		udp_tunnel6_xmit_skb(ndst, sk, skb, dev,
-				     &src->sin6.sin6_addr,
+				     &local_ip.sin6.sin6_addr,
 				     &dst->sin6.sin6_addr, tos, ttl,
 				     label, src_port, dst_port, !udp_sum);
 #endif


Patches currently in stable-queue which might be from brussell@brocade.com are

queue-4.9/vxlan-don-t-allow-overwrite-of-config-src-addr.patch