ofproto-dpif-xlate: Fix confusion between "no stp port" and "stp port 0".

Commit 9d189a50e (ofproto-dpif-xlate: Pull STP xlation into
ofproto-dpif-xlate.) introduced the bug that considers 'stp_port_no'
of 0 as stp disabled on the port.  However 'stp_port_no' is
actually the index of the stp struct's port array and ranges
between [0, STP_MAX_PORTS).  So the bug allows the blocked
port keep transmitting packets and generates loop.

This commit fixes this bug.

Signed-off-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c
index c41013c..feee71c 100644 (file)
--- a/ofproto/ofproto-dpif-xlate.c
+++ b/ofproto/ofproto-dpif-xlate.c
@@ -121,7 +121,7 @@ struct xport {
     struct xport *peer;              /* Patch port peer or null. */
 
     enum ofputil_port_config config; /* OpenFlow port configuration. */
-    int stp_port_no;                 /* STP port number or 0 if not in use. */
+    int stp_port_no;                 /* STP port number or -1 if not in use. */
 
     struct hmap skb_priorities;      /* Map of 'skb_priority_to_dscp's. */
 
@@ -621,7 +621,7 @@ xport_lookup(const struct ofport_dpif *ofport)
 static struct stp_port *
 xport_get_stp_port(const struct xport *xport)
 {
-    return xport->xbridge->stp && xport->stp_port_no
+    return xport->xbridge->stp && xport->stp_port_no != -1
         ? stp_get_port(xport->xbridge->stp, xport->stp_port_no)
         : NULL;
 }

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index f20fb52..58a4d94 100644 (file)
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -822,7 +822,7 @@ type_run(const char *type)
             HMAP_FOR_EACH (ofport, up.hmap_node, &ofproto->up.ports) {
                 int stp_port = ofport->stp_port
                     ? stp_port_no(ofport->stp_port)
-                    : 0;
+                    : -1;
                 xlate_ofport_set(ofproto, ofport->bundle, ofport,
                                  ofport->up.ofp_port, ofport->odp_port,
                                  ofport->up.netdev, ofport->cfm,