[libvirt] [PATCH] Fix nwfilter driver reload/shutdown handling when unprivileged

[Daniel P. Berrange]

From: "Daniel P. Berrange" <berrange at redhat.com>

Although the nwfilter driver skips startup when running in a
session libvirtd, it did not skip reload or shutdown. This
caused errors to be reported when sending SIGHUP to libvirtd,
and caused an abort() in libdbus on shutdown due to trying
to remove a dbus filter that was never added

NB, this was previously part of my large refactoring series

https://www.redhat.com/archives/libvir-list/2013-January/msg01411.html

but I've pulled it out since I noticed it has SEGV impact.


---
 src/conf/nwfilter_conf.h       |  1 +
 src/nwfilter/nwfilter_driver.c | 31 +++++++++++++++++++------------
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/src/conf/nwfilter_conf.h b/src/conf/nwfilter_conf.h
index ca2c070..35f8dde 100644
--- a/src/conf/nwfilter_conf.h
+++ b/src/conf/nwfilter_conf.h
@@ -556,6 +556,7 @@ typedef struct _virNWFilterDriverState virNWFilterDriverState;
 typedef virNWFilterDriverState *virNWFilterDriverStatePtr;
 struct _virNWFilterDriverState {
     virMutex lock;
+    bool privileged;
 
     virNWFilterObjList nwfilters;
 
diff --git a/src/nwfilter/nwfilter_driver.c b/src/nwfilter/nwfilter_driver.c
index b67b704..19ebb03 100644
--- a/src/nwfilter/nwfilter_driver.c
+++ b/src/nwfilter/nwfilter_driver.c
@@ -165,7 +165,7 @@ nwfilterDriverInstallDBusMatches(DBusConnection *sysbus ATTRIBUTE_UNUSED)
  * Initialization function for the QEmu daemon
  */
 static int
-nwfilterDriverStartup(bool privileged ATTRIBUTE_UNUSED,
+nwfilterDriverStartup(bool privileged,
                       virStateInhibitCallback callback ATTRIBUTE_UNUSED,
                       void *opaque ATTRIBUTE_UNUSED)
 {
@@ -185,6 +185,7 @@ nwfilterDriverStartup(bool privileged ATTRIBUTE_UNUSED,
         goto err_free_driverstate;
 
     driverState->watchingFirewallD = (sysbus != NULL);
+    driverState->privileged = privileged;
 
     if (!privileged)
         return 0;
@@ -275,6 +276,9 @@ nwfilterDriverReload(void) {
         return -1;
     }
 
+    if (!driverState->privileged)
+        return 0;
+
     conn = virConnectOpen("qemu:///system");
 
     if (conn) {
@@ -333,21 +337,24 @@ nwfilterDriverShutdown(void) {
     if (!driverState)
         return -1;
 
-    virNWFilterConfLayerShutdown();
-    virNWFilterTechDriversShutdown();
-    virNWFilterDHCPSnoopShutdown();
-    virNWFilterLearnShutdown();
-    virNWFilterIPAddrMapShutdown();
+    if (driverState->privileged) {
+        virNWFilterConfLayerShutdown();
+        virNWFilterTechDriversShutdown();
+        virNWFilterDHCPSnoopShutdown();
+        virNWFilterLearnShutdown();
+        virNWFilterIPAddrMapShutdown();
 
-    nwfilterDriverLock(driverState);
+        nwfilterDriverLock(driverState);
 
-    nwfilterDriverRemoveDBusMatches();
+        nwfilterDriverRemoveDBusMatches();
 
-    /* free inactive nwfilters */
-    virNWFilterObjListFree(&driverState->nwfilters);
+        /* free inactive nwfilters */
+        virNWFilterObjListFree(&driverState->nwfilters);
+
+        VIR_FREE(driverState->configDir);
+        nwfilterDriverUnlock(driverState);
+    }
 
-    VIR_FREE(driverState->configDir);
-    nwfilterDriverUnlock(driverState);
     virMutexDestroy(&driverState->lock);
     VIR_FREE(driverState);
 
-- 
1.8.0.2