[PATCH 01/17] BRIDGE: Fix faulty check in br_stp_recalculate_bridge_id()

From: Chris Wright
Date: Thu Jan 12 2006 - 22:22:46 EST


-stable review patch. If anyone has any objections, please let us know.
------------------

There is a regression in 2.6.15.
One of the conversions from memcmp to compare_ether_addr is incorrect.
We need to do relative comparison to determine min MAC address to
use in bridge id. This will cause the wrong bridge id to be chosen
which violates 802.1d Spanning Tree Protocol, and may create forwarding
loops.

Signed-off-by: Stephen Hemminger <shemminger@xxxxxxxx>
Signed-off-by: Chris Wright <chrisw@xxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
---

net/bridge/br_stp_if.c | 2 +-
1 files changed, 1 insertion(+), 1 deletion(-)

Index: linux-2.6.15.y/net/bridge/br_stp_if.c
===================================================================
--- linux-2.6.15.y.orig/net/bridge/br_stp_if.c
+++ linux-2.6.15.y/net/bridge/br_stp_if.c
@@ -158,7 +158,7 @@ void br_stp_recalculate_bridge_id(struct

list_for_each_entry(p, &br->port_list, list) {
if (addr == br_mac_zero ||
- compare_ether_addr(p->dev->dev_addr, addr) < 0)
+ memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0)
addr = p->dev->dev_addr;

}

--
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/