[v2.6.34-stable 049/213] bridge: set priority of STP packets

From: Paul Gortmaker
Date: Wed Feb 05 2014 - 16:03:37 EST


From: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>

-------------------
This is a commit scheduled for the next v2.6.34 longterm release.
http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
If you see a problem with using this for longterm, please comment.
-------------------

commit 547b4e718115eea74087e28d7fa70aec619200db upstream.

Spanning Tree Protocol packets should have always been marked as
control packets, this causes them to get queued in the high prirority
FIFO. As Radia Perlman mentioned in her LCA talk, STP dies if bridge
gets overloaded and can't communicate. This is a long-standing bug back
to the first versions of Linux bridge.

Signed-off-by: Stephen Hemminger <stephen@xxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Paul Gortmaker <paul.gortmaker@xxxxxxxxxxxxx>
---
net/bridge/br_stp_bpdu.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/bridge/br_stp_bpdu.c b/net/bridge/br_stp_bpdu.c
index edc7111b3db8..9fd76244adf6 100644
--- a/net/bridge/br_stp_bpdu.c
+++ b/net/bridge/br_stp_bpdu.c
@@ -16,6 +16,7 @@
#include <linux/etherdevice.h>
#include <linux/llc.h>
#include <linux/slab.h>
+#include <linux/pkt_sched.h>
#include <net/net_namespace.h>
#include <net/llc.h>
#include <net/llc_pdu.h>
@@ -40,6 +41,7 @@ static void br_send_bpdu(struct net_bridge_port *p,

skb->dev = p->dev;
skb->protocol = htons(ETH_P_802_2);
+ skb->priority = TC_PRIO_CONTROL;

skb_reserve(skb, LLC_RESERVE);
memcpy(__skb_put(skb, length), data, length);
--
1.8.5.2

--
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/