From: John Ferlan <jferlan@redhat.com>
Date: Fri, 9 Feb 2018 13:52:10 +0000 (-0500)
Subject: qemu: Alter condition to avoid possible NULL deref
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=a1bce9ef8632cd2015c800e4e2c0b0ed08709311;p=libvirt.git

qemu: Alter condition to avoid possible NULL deref

Commit 'f0f2a5ec2' neglected to adjust the if condition to split
out the possibility that the @watchdog is NULL when altering the
message to add detail about the model.

Just split out the condition and use previous/original message, but
with the new message code.

Found by Coverity

Signed-off-by: John Ferlan <jferlan@redhat.com>
---

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index c7bf25eeef..3291ce6130 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -5159,11 +5159,16 @@ qemuDomainDetachWatchdog(virQEMUDriverPtr driver,
     virDomainWatchdogDefPtr watchdog = vm->def->watchdog;
     qemuDomainObjPrivatePtr priv = vm->privateData;
 
+    if (!watchdog) {
+        virReportError(VIR_ERR_DEVICE_MISSING, "%s",
+                       _("watchdog device not present in domain configuration"));
+        return -1;
+    }
+
     /* While domains can have up to one watchdog, the one supplied by the user
      * doesn't necessarily match the one domain has. Refuse to detach in such
      * case. */
-    if (!(watchdog &&
-          watchdog->model == dev->model &&
+    if (!(watchdog->model == dev->model &&
           watchdog->action == dev->action &&
           virDomainDeviceInfoAddressIsEqual(&dev->info, &watchdog->info))) {
         virReportError(VIR_ERR_DEVICE_MISSING,