network: make it safe to call networkSetupPrivateChains() multiple times

networkSetupPrivateChains() is currently called only once per run of
libvirtd, so it can assume that errInitV4 and errInitV6 are empty/null
when it is called. In preparation for potentially calling this
function multiple times during one run, this patch moves the reset of
errInitV[46] to the top of the function, to assure no memory is
leaked.
Signed-off-by: NLaine Stump <laine@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

src/network/bridge_driver_linux.c

@@ -48,6 +48,10 @@ static void networkSetupPrivateChains(void)
     VIR_DEBUG("Setting up global firewall chains");
 
     createdChains = false;
+    virFreeError(errInitV4);
+    errInitV4 = NULL;
+    virFreeError(errInitV6);
+    errInitV6 = NULL;
 
     rc = iptablesSetupPrivateChains(VIR_FIREWALL_LAYER_IPV4);
     if (rc < 0) {
@@ -56,8 +60,6 @@ static void networkSetupPrivateChains(void)
         errInitV4 = virSaveLastError();
         virResetLastError();
     } else {
-        virFreeError(errInitV4);
-        errInitV4 = NULL;
         if (rc) {
             VIR_DEBUG("Created global IPv4 chains");
             createdChains = true;
@@ -73,8 +75,6 @@ static void networkSetupPrivateChains(void)
         errInitV6 = virSaveLastError();
         virResetLastError();
     } else {
-        virFreeError(errInitV6);
-        errInitV6 = NULL;
         if (rc) {
             VIR_DEBUG("Created global IPv6 chains");
             createdChains = true;