[qemu-s390x] [PATCH v2] s390: avoid potential null dereference in s390_pcihost_unplug()

[Li Qiang]

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 <address@hidden>
---
Adds a default branch for device plug per Cornelia's review.

 hw/s390x/s390-pci-bus.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 15759b6514..fe48a36ff6 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -912,6 +912,9 @@ 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 {
+        error_setg(errp, "s390: device plug request for not supported device"
+                   " type: %s", object_get_typename(OBJECT(dev)));
     }
 }
 
@@ -956,6 +959,10 @@ 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 {
+        error_setg(errp, "s390: device unplug request for not supported device"
+                   " type: %s", object_get_typename(OBJECT(dev)));
+        return;
     }
 
     switch (pbdev->state) {
-- 
2.17.1