Fix possible crash in handling IO Error event

If the IO error event does not include a reason, then there
is a possible crash dispatching the event

* src/conf/domain_event.c: Missing check for a NULL reason before
  strduping allows for a crash

diff --git a/src/conf/domain_event.c b/src/conf/domain_event.c
index e5bd4583477b28b32755e47208bcef05092f7fa3..e88aafea8cb2a5377d18b35db46f2f0ef98c48f5 100644 (file)
--- a/src/conf/domain_event.c
+++ b/src/conf/domain_event.c
@@ -671,7 +671,7 @@ static virDomainEventPtr virDomainEventIOErrorNewFromObjImpl(int event,
         ev->data.ioError.action = action;
         if (!(ev->data.ioError.srcPath = strdup(srcPath)) ||
             !(ev->data.ioError.devAlias = strdup(devAlias)) ||
-            !(ev->data.ioError.reason = strdup(reason))) {
+            (reason && !(ev->data.ioError.reason = strdup(reason)))) {
             virDomainEventFree(ev);
             ev = NULL;
         }