Fix crash in libvirtd when events are registered & ACLs active

When a client disconnects from libvirtd, all event callbacks
must be removed. This involves running the public API

  virConnectDomainEventDeregisterAny

This code does not run in normal API dispatch context, so no
identity was set. The result was that the access control drivers
denied the attempt to deregister callbacks. The callbacks thus
continued to trigger after the client was free'd causing fairly
predictable use of free memory & a crash.

This can be triggered by any client with readonly access when
the ACL drivers are active.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 8294aa0c1750dcb49d6345cd9bd97bf421580d8b)

Conflicts:
	daemon/remote.c: int/size_t changes

diff --git a/daemon/remote.c b/daemon/remote.c
index 37572dedd565dd0213cb9cd72dd9519aa819e749..c0a5618688a659bc81b1a91c58118c7b4002c7b0 100644 (file)
--- a/daemon/remote.c
+++ b/daemon/remote.c
@@ -638,8 +638,11 @@ void remoteClientFreeFunc(void *data)
 
     /* Deregister event delivery callback */
     if (priv->conn) {
+        virIdentityPtr sysident = virIdentityGetSystem();
         int i;
 
+        virIdentitySetCurrent(sysident);
+
         for (i = 0; i < VIR_DOMAIN_EVENT_ID_LAST; i++) {
             if (priv->domainEventCallbackID[i] != -1) {
                 VIR_DEBUG("Deregistering to relay remote events %d", i);
@@ -650,6 +653,9 @@ void remoteClientFreeFunc(void *data)
         }
 
         virConnectClose(priv->conn);
+
+        virIdentitySetCurrent(NULL);
+        virObjectUnref(sysident);
     }
 
     VIR_FREE(priv);