s390: avoid potential null dereference in s390_pcihost_unplug()

When getting the 'pbdev', the if...else has no default branch.
From Coverity, the 'pbdev' maybe null when the 'dev' is not
the TYPE_PCI_BRIDGE/TYPE_PCI_DEVICE/TYPE_S390_PCI_DEVICE.
This patch adds a default branch for device plug and unplug.

Spotted by Coverity: CID 1398593

Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20190108151114.33140-1-liq3ea@163.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Collin Walling <walling@linux.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 15759b6514a504a49f4eb132c5665aeac685c768..a94700a78c8e865211910175406ac8969921cfb3 100644 (file)
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -912,6 +912,8 @@ static void s390_pcihost_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
         pbdev->fh = pbdev->idx;
         QTAILQ_INSERT_TAIL(&s->zpci_devs, pbdev, link);
         g_hash_table_insert(s->zpci_table, &pbdev->idx, pbdev);
+    } else {
+        g_assert_not_reached();
     }
 }
 
@@ -956,6 +958,8 @@ static void s390_pcihost_unplug(HotplugHandler *hotplug_dev, DeviceState *dev,
     } else if (object_dynamic_cast(OBJECT(dev), TYPE_S390_PCI_DEVICE)) {
         pbdev = S390_PCI_DEVICE(dev);
         pci_dev = pbdev->pdev;
+    } else {
+        g_assert_not_reached();
     }
 
     switch (pbdev->state) {