commit 19bb3506e27096eea5f7b71b89621ad1203ed318
author Evgeny Kravtsunov <emkravts@openvz.org> Tue Apr 17 12:31:24 2007 -0700
committer David S. Miller <davem@sunset.davemloft.net> Tue Apr 17 14:16:00 2007 -0700
tree f3385d69595ab50fffbc314b281864ef99f2071b
parent 0304ff8a2d5f57defb011c7f261b4c1b3eff96d1

[BRIDGE]: Unaligned access when comparing ethernet addresses

compare_ether_addr() implicitly requires that the addresses
passed are 2-bytes aligned in memory.

This is not true for br_stp_change_bridge_id() and
br_stp_recalculate_bridge_id() in which one of the addresses
is unsigned char *, and thus may not be 2-bytes aligned.

Signed-off-by: Evgeny Kravtsunov <emkravts@openvz.org>
Signed-off-by: Kirill Korotaev <dev@openvz.org>
Signed-off-by: Pavel Emelianov <xemul@openvz.org>

net/bridge/br_stp_if.c

diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
index 58d13f2..a285897 100644
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -126,7 +126,9 @@
 /* called under bridge lock */
 void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *addr)
 {
-	unsigned char oldaddr[6];
+	/* should be aligned on 2 bytes for compare_ether_addr() */
+	unsigned short oldaddr_aligned[ETH_ALEN >> 1];
+	unsigned char *oldaddr = (unsigned char *)oldaddr_aligned;
 	struct net_bridge_port *p;
 	int wasroot;
 
@@ -151,11 +153,14 @@
 		br_become_root_bridge(br);
 }
 
-static const unsigned char br_mac_zero[6];
+/* should be aligned on 2 bytes for compare_ether_addr() */
+static const unsigned short br_mac_zero_aligned[ETH_ALEN >> 1];
 
 /* called under bridge lock */
 void br_stp_recalculate_bridge_id(struct net_bridge *br)
 {
+	const unsigned char *br_mac_zero =
+			(const unsigned char *)br_mac_zero_aligned;
 	const unsigned char *addr = br_mac_zero;
 	struct net_bridge_port *p;