qdev: don't crash on unset drive properties.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
index c4fb15c02046eacc3ce3692499e2cec46c8aa29d..5c627fae40819ce19c49b31adff3a51bdd39ebca 100644 (file)
--- a/hw/qdev-properties.c
+++ b/hw/qdev-properties.c
@@ -208,7 +208,7 @@ static int parse_drive(DeviceState *dev, Property *prop, const char *str)
 static int print_drive(DeviceState *dev, Property *prop, char *dest, size_t len)
 {
     DriveInfo **ptr = qdev_get_prop_ptr(dev, prop);
-    return snprintf(dest, len, "%s", (*ptr)->id);
+    return snprintf(dest, len, "%s", (*ptr) ? (*ptr)->id : "<null>");
 }
 
 PropertyInfo qdev_prop_drive = {