kern/93909: STP doesn't transmit its own bridge id

[Onno Molenkamp]

>Number:         93909
>Category:       kern
>Synopsis:       STP doesn't transmit its own bridge id
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Feb 27 18:50:06 GMT 2006
>Closed-Date:
>Last-Modified:
>Originator:     Onno Molenkamp
>Release:        6.0-STABLE
>Organization:
>Environment:
FreeBSD duiveltje 6.0-STABLE FreeBSD 6.0-STABLE #0: Mon Jan 16 13:54:19 CET 2006     root at duiveltje:/usr/obj/usr/src/sys/DUIVELTJE  i386

>Description:
The code in net/bridgestp.c that builds up a packet to be transmitted over the network incorrectly puts the root id in the bridge id field.

I noticed this behaviour in 6.0-STABLE version from a while ago, but the bug still exists in current CVS.
>How-To-Repeat:
Use an if_bridge bridge with STP.
>Fix:
--- net/bridgestp.c     Tue Jan 10 00:53:40 2006
+++ net/bridgestp.c.new      Mon Feb 27 19:42:24 2006
@@ -269,13 +269,13 @@

        bpdu.cbu_rootpathcost = htonl(cu->cu_root_path_cost);

-       bpdu.cbu_bridgepri = htons(cu->cu_rootid >> 48);
-       bpdu.cbu_bridgeaddr[0] = cu->cu_rootid >> 40;
-       bpdu.cbu_bridgeaddr[1] = cu->cu_rootid >> 32;
-       bpdu.cbu_bridgeaddr[2] = cu->cu_rootid >> 24;
-       bpdu.cbu_bridgeaddr[3] = cu->cu_rootid >> 16;
-       bpdu.cbu_bridgeaddr[4] = cu->cu_rootid >> 8;
-       bpdu.cbu_bridgeaddr[5] = cu->cu_rootid >> 0;
+       bpdu.cbu_bridgepri = htons(cu->cu_bridge_id >> 48);
+       bpdu.cbu_bridgeaddr[0] = cu->cu_bridge_id >> 40;
+       bpdu.cbu_bridgeaddr[1] = cu->cu_bridge_id >> 32;
+       bpdu.cbu_bridgeaddr[2] = cu->cu_bridge_id >> 24;
+       bpdu.cbu_bridgeaddr[3] = cu->cu_bridge_id >> 16;
+       bpdu.cbu_bridgeaddr[4] = cu->cu_bridge_id >> 8;
+       bpdu.cbu_bridgeaddr[5] = cu->cu_bridge_id >> 0;

        bpdu.cbu_portid = htons(cu->cu_port_id);
        bpdu.cbu_messageage = htons(cu->cu_message_age);

>Release-Note:
>Audit-Trail:
>Unformatted: