Patch "batman-adv: Fix potentially broken skb network header access" has been added to the 4.1-stable tree

Patch "batman-adv: Fix potentially broken skb network header access" has been added to the 4.1-stable tree

[gregkh]

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

    batman-adv: Fix potentially broken skb network header access

to the 4.1-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:
     batman-adv-fix-potentially-broken-skb-network-header-access.patch
and it can be found in the queue-4.1 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 53cf037bf846417fd92dc92ddf97267f69b110f4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>
Date: Tue, 30 Jun 2015 23:45:26 +0200
Subject: batman-adv: Fix potentially broken skb network header access
MIME-Version: 1.0
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From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>

commit 53cf037bf846417fd92dc92ddf97267f69b110f4 upstream.

The two commits noted below added calls to ip_hdr() and ipv6_hdr(). They
need a correctly set skb network header.

Unfortunately we cannot rely on the device drivers to set it for us.
Therefore setting it in the beginning of the according ndo_start_xmit
handler.

Fixes: 1d8ab8d3c176 ("batman-adv: Modified forwarding behaviour for multicast packets")
Fixes: ab49886e3da7 ("batman-adv: Add IPv4 link-local/IPv6-ll-all-nodes multicast support")
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/batman-adv/soft-interface.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -172,6 +172,7 @@ static int batadv_interface_tx(struct sk
 	int gw_mode;
 	enum batadv_forw_mode forw_mode;
 	struct batadv_orig_node *mcast_single_orig = NULL;
+	int network_offset = ETH_HLEN;
 
 	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 		goto dropped;
@@ -184,14 +185,18 @@ static int batadv_interface_tx(struct sk
 	case ETH_P_8021Q:
 		vhdr = vlan_eth_hdr(skb);
 
-		if (vhdr->h_vlan_encapsulated_proto != ethertype)
+		if (vhdr->h_vlan_encapsulated_proto != ethertype) {
+			network_offset += VLAN_HLEN;
 			break;
+		}
 
 		/* fall through */
 	case ETH_P_BATMAN:
 		goto dropped;
 	}
 
+	skb_set_network_header(skb, network_offset);
+
 	if (batadv_bla_tx(bat_priv, skb, vid))
 		goto dropped;
 


Patches currently in stable-queue which might be from linus.luessing@c0d3.blue are

queue-4.1/batman-adv-fix-potential-synchronization-issues-in-mcast-tvlv-handler.patch
queue-4.1/batman-adv-make-tt-capability-changes-atomic.patch
queue-4.1/batman-adv-make-dat-capability-changes-atomic.patch
queue-4.1/batman-adv-make-nc-capability-changes-atomic.patch
queue-4.1/batman-adv-fix-potentially-broken-skb-network-header-access.patch
queue-4.1/batman-adv-make-mcast-capability-changes-atomic.patch