[PATCH] tools/xenstore: fix event sending in introduce_domain()

[Juergen Gross <jgross@xxxxxxxx>]

Commit fc2b57c9af46 ("xenstored: send an evtchn notification on
introduce_domain") introduced a potential NULL dereference in case of
Xenstore live update.

Fix that by adding an appropriate check.

Coverity-Id: 1504572
Fixes: fc2b57c9af46 ("xenstored: send an evtchn notification on 
introduce_domain")
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 tools/xenstore/xenstored_domain.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/xenstore/xenstored_domain.c 
b/tools/xenstore/xenstored_domain.c
index de88bf2a68..ead4c237d2 100644
--- a/tools/xenstore/xenstored_domain.c
+++ b/tools/xenstore/xenstored_domain.c
@@ -493,9 +493,11 @@ static struct domain *introduce_domain(const void *ctx,
                /* Now domain belongs to its connection. */
                talloc_steal(domain->conn, domain);
 
-               /* Notify the domain that xenstore is available */
-               interface->connection = XENSTORE_CONNECTED;
-               xenevtchn_notify(xce_handle, domain->port);
+               if (!restore) {
+                       /* Notify the domain that xenstore is available */
+                       interface->connection = XENSTORE_CONNECTED;
+                       xenevtchn_notify(xce_handle, domain->port);
+               }
 
                if (!is_master_domain && !restore)
                        fire_watches(NULL, ctx, "@introduceDomain", NULL,
-- 
2.35.3