From 5e465df6be8bcb00f0b4bff831e91f4042fae272 Mon Sep 17 00:00:00 2001
From: Kyle Mestery <kmestery@cisco.com>
Date: Wed, 29 Aug 2012 14:44:36 -0400
Subject: [PATCH] Fix a crash when using Open vSwitch virtual ports

Fixup buffer usage when handling VLANs. Also fix the logic
used to determine if the virNetDevVlanPtr is valid or not.
Fixes crashes in the latest code when using Open vSwitch
virtualports.

Signed-off-by: Kyle Mestery <kmestery@cisco.com>
---
 src/util/virnetdevopenvswitch.c | 25 ++++++++++++-------------
 1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c
index b903ae4ee6..06debd7912 100644
--- a/src/util/virnetdevopenvswitch.c
+++ b/src/util/virnetdevopenvswitch.c
@@ -59,7 +59,7 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
     char *ifaceid_ex_id = NULL;
     char *profile_ex_id = NULL;
     char *vmid_ex_id = NULL;
-    virBufferPtr buf;
+    virBuffer buf = VIR_BUFFER_INITIALIZER;
 
     virMacAddrFormat(macaddr, macaddrstr);
     virUUIDFormat(ovsport->interfaceID, ifuuidstr);
@@ -79,13 +79,12 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
                         ovsport->profileID) < 0)
             goto out_of_memory;
     }
-    if (virtVlan) {
-        if (VIR_ALLOC(buf) < 0)
-            goto out_of_memory;
+
+    if (virtVlan && virtVlan->nTags > 0) {
 
         /* Trunk port first */
-        if (virtVlan->trunk) {
-            virBufferAddLit(buf, "trunk=");
+        if (virtVlan->trunk == true) {
+            virBufferAddLit(&buf, "trunk=");
 
             /*
              * Trunk ports have at least one VLAN. Do the first one
@@ -93,21 +92,21 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
              * start of the for loop if there are more than one VLANs
              * on this trunk port.
              */
-            virBufferAsprintf(buf, "%d", virtVlan->tag[i]);
+            virBufferAsprintf(&buf, "%d", virtVlan->tag[i]);
 
             for (i = 1; i < virtVlan->nTags; i++) {
-                virBufferAddLit(buf, ",");
-                virBufferAsprintf(buf, "%d", virtVlan->tag[i]);
+                virBufferAddLit(&buf, ",");
+                virBufferAsprintf(&buf, "%d", virtVlan->tag[i]);
             }
         } else if (virtVlan->nTags) {
-            virBufferAsprintf(buf, "tag=%d", virtVlan->tag[0]);
+            virBufferAsprintf(&buf, "tag=%d", virtVlan->tag[0]);
         }
     }
 
     cmd = virCommandNew(OVSVSCTL);
     if (ovsport->profileID[0] == '\0') {
         virCommandAddArgList(cmd, "--", "--may-exist", "add-port",
-                        brname, ifname, virBufferContentAndReset(buf),
+                        brname, ifname, virBufferCurrentContent(&buf),
                         "--", "set", "Interface", ifname, attachedmac_ex_id,
                         "--", "set", "Interface", ifname, ifaceid_ex_id,
                         "--", "set", "Interface", ifname, vmid_ex_id,
@@ -116,7 +115,7 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
                         NULL);
     } else {
         virCommandAddArgList(cmd, "--", "--may-exist", "add-port",
-                        brname, ifname, virBufferContentAndReset(buf),
+                        brname, ifname, virBufferCurrentContent(&buf),
                         "--", "set", "Interface", ifname, attachedmac_ex_id,
                         "--", "set", "Interface", ifname, ifaceid_ex_id,
                         "--", "set", "Interface", ifname, vmid_ex_id,
@@ -135,7 +134,7 @@ int virNetDevOpenvswitchAddPort(const char *brname, const char *ifname,
 
     ret = 0;
 cleanup:
-    VIR_FREE(buf);
+    virBufferFreeAndReset(&buf);
     VIR_FREE(attachedmac_ex_id);
     VIR_FREE(ifaceid_ex_id);
     VIR_FREE(vmid_ex_id);
-- 
GitLab