From fbf1aba32d294073c705f2e40f9847bd4f718cbe Mon Sep 17 00:00:00 2001
From: =?utf8?q?J=C3=A1n=20Tomko?= <jtomko@redhat.com>
Date: Fri, 26 Jul 2013 12:04:32 +0200
Subject: [PATCH] Set the number of elements 0 in virNetwork*Clear

Decrementing it when it was already 0 causes an invalid free
in virNetworkDefUpdateDNSHost if virNetworkDNSHostDefParseXML
fails and virNetworkDNSHostDefClear gets called twice.

virNetworkForwardDefClear left the number untouched even if it
freed all the elements.
(cherry picked from commit c4e23388e6c7f769e45d1c162f880cd81e4d4d3b)
---
 src/conf/network_conf.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c
index c909756f79..fdcede80ef 100644
--- a/src/conf/network_conf.c
+++ b/src/conf/network_conf.c
@@ -134,8 +134,8 @@ virNetworkIpDefClear(virNetworkIpDefPtr def)
     VIR_FREE(def->family);
     VIR_FREE(def->ranges);
 
-    while (def->nhosts--)
-        virNetworkDHCPHostDefClear(&def->hosts[def->nhosts]);
+    while (def->nhosts)
+        virNetworkDHCPHostDefClear(&def->hosts[--def->nhosts]);
 
     VIR_FREE(def->hosts);
     VIR_FREE(def->tftproot);
@@ -158,8 +158,8 @@ virNetworkDNSTxtDefClear(virNetworkDNSTxtDefPtr def)
 static void
 virNetworkDNSHostDefClear(virNetworkDNSHostDefPtr def)
 {
-    while (def->nnames--)
-        VIR_FREE(def->names[def->nnames]);
+    while (def->nnames)
+        VIR_FREE(def->names[--def->nnames]);
     VIR_FREE(def->names);
 }
 
@@ -176,18 +176,18 @@ static void
 virNetworkDNSDefClear(virNetworkDNSDefPtr def)
 {
     if (def->txts) {
-        while (def->ntxts--)
-            virNetworkDNSTxtDefClear(&def->txts[def->ntxts]);
+        while (def->ntxts)
+            virNetworkDNSTxtDefClear(&def->txts[--def->ntxts]);
         VIR_FREE(def->txts);
     }
     if (def->hosts) {
-        while (def->nhosts--)
-            virNetworkDNSHostDefClear(&def->hosts[def->nhosts]);
+        while (def->nhosts)
+            virNetworkDNSHostDefClear(&def->hosts[--def->nhosts]);
         VIR_FREE(def->hosts);
     }
     if (def->srvs) {
-        while (def->nsrvs--)
-            virNetworkDNSSrvDefClear(&def->srvs[def->nsrvs]);
+        while (def->nsrvs)
+            virNetworkDNSSrvDefClear(&def->srvs[--def->nsrvs]);
         VIR_FREE(def->srvs);
     }
 }
@@ -206,6 +206,7 @@ virNetworkForwardDefClear(virNetworkForwardDefPtr def)
         virNetworkForwardIfDefClear(&def->ifs[ii]);
     }
     VIR_FREE(def->ifs);
+    def->nifs = def->npfs = 0;
 }
 
 void
-- 
2.47.3