Fix vmdef usage after domain crash in monitor on device detach

https://bugzilla.redhat.com/show_bug.cgi?id=1161024

In the device type-specific functions, exit early
if the domain has disappeared, because the cleanup
should have been done by qemuProcessStop.

Check the return value in processDeviceDeletedEvent
and qemuProcessUpdateDevices.

Skip audit and removing the device from live def because
it has already been cleaned up.

src/qemu/qemu_driver.c

@@ -4048,7 +4048,8 @@ processDeviceDeletedEvent(virQEMUDriverPtr driver,
     if (virDomainDefFindDevice(vm->def, devAlias, &dev, true) < 0)
         goto endjob;
 
-    qemuDomainRemoveDevice(driver, vm, &dev);
+    if (qemuDomainRemoveDevice(driver, vm, &dev) < 0)
+        goto endjob;
 
     if (virDomainSaveStatus(driver->xmlopt, cfg->stateDir, vm) < 0)
         VIR_WARN("unable to save domain status after removing device %s",

src/qemu/qemu_hotplug.c

@@ -2499,8 +2499,9 @@ qemuDomainRemoveDiskDevice(virQEMUDriverPtr driver,
 
     qemuDomainObjEnterMonitor(driver, vm);
     qemuMonitorDriveDel(priv->mon, drivestr);
-    qemuDomainObjExitMonitor(driver, vm);
     VIR_FREE(drivestr);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        return -1;
 
     virDomainAuditDisk(vm, disk->src, NULL, "detach", true);
 
@@ -2615,7 +2616,8 @@ qemuDomainRemoveHostDevice(virQEMUDriverPtr driver,
 
         qemuDomainObjEnterMonitor(driver, vm);
         qemuMonitorDriveDel(priv->mon, drivestr);
-        qemuDomainObjExitMonitor(driver, vm);
+        if (qemuDomainObjExitMonitor(driver, vm) < 0)
+            goto cleanup;
     }
 
     event = virDomainEventDeviceRemovedNewFromObj(vm, hostdev->info->alias);
@@ -2709,7 +2711,8 @@ qemuDomainRemoveNetDevice(virQEMUDriverPtr driver,
     if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_NETDEV) &&
         virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE)) {
         if (qemuMonitorRemoveNetdev(priv->mon, hostnet_name) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditNet(vm, net, NULL, "detach", false);
             goto cleanup;
         }
@@ -2721,12 +2724,14 @@ qemuDomainRemoveNetDevice(virQEMUDriverPtr driver,
                 virReportError(VIR_ERR_OPERATION_FAILED, "%s",
                                _("unable to determine original VLAN"));
             }
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditNet(vm, net, NULL, "detach", false);
             goto cleanup;
         }
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     virDomainAuditNet(vm, net, NULL, "detach", true);
 
@@ -2796,7 +2801,8 @@ qemuDomainRemoveChrDevice(virQEMUDriverPtr driver,
 
     qemuDomainObjEnterMonitor(driver, vm);
     rc = qemuMonitorDetachCharDev(priv->mon, charAlias);
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     virDomainAuditChardev(vm, chr, NULL, "detach", rc == 0);
 
@@ -2817,27 +2823,28 @@ qemuDomainRemoveChrDevice(virQEMUDriverPtr driver,
 }
 
 
-void
+int
 qemuDomainRemoveDevice(virQEMUDriverPtr driver,
                        virDomainObjPtr vm,
                        virDomainDeviceDefPtr dev)
 {
+    int ret = -1;
     switch ((virDomainDeviceType) dev->type) {
     case VIR_DOMAIN_DEVICE_DISK:
-        qemuDomainRemoveDiskDevice(driver, vm, dev->data.disk);
+        ret = qemuDomainRemoveDiskDevice(driver, vm, dev->data.disk);
         break;
     case VIR_DOMAIN_DEVICE_CONTROLLER:
-        qemuDomainRemoveControllerDevice(driver, vm, dev->data.controller);
+        ret = qemuDomainRemoveControllerDevice(driver, vm, dev->data.controller);
         break;
     case VIR_DOMAIN_DEVICE_NET:
-        qemuDomainRemoveNetDevice(driver, vm, dev->data.net);
+        ret = qemuDomainRemoveNetDevice(driver, vm, dev->data.net);
         break;
     case VIR_DOMAIN_DEVICE_HOSTDEV:
-        qemuDomainRemoveHostDevice(driver, vm, dev->data.hostdev);
+        ret = qemuDomainRemoveHostDevice(driver, vm, dev->data.hostdev);
         break;
 
     case VIR_DOMAIN_DEVICE_CHR:
-        qemuDomainRemoveChrDevice(driver, vm, dev->data.chr);
+        ret = qemuDomainRemoveChrDevice(driver, vm, dev->data.chr);
         break;
 
     case VIR_DOMAIN_DEVICE_NONE:
@@ -2863,6 +2870,7 @@ qemuDomainRemoveDevice(virQEMUDriverPtr driver,
                        virDomainDeviceTypeToString(dev->type));
         break;
     }
+    return ret;
 }
 
 
@@ -2986,19 +2994,22 @@ qemuDomainDetachVirtioDiskDevice(virQEMUDriverPtr driver,
     qemuDomainObjEnterMonitor(driver, vm);
     if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE)) {
         if (qemuMonitorDelDevice(priv->mon, detach->info.alias) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditDisk(vm, detach->src, NULL, "detach", false);
             goto cleanup;
         }
     } else {
         if (qemuMonitorRemovePCIDevice(priv->mon,
                                        &detach->info.addr.pci) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditDisk(vm, detach->src, NULL, "detach", false);
             goto cleanup;
         }
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     rc = qemuDomainWaitForDeviceRemoval(vm);
     if (rc == 0 || rc == 1)
@@ -3038,11 +3049,13 @@ qemuDomainDetachDiskDevice(virQEMUDriverPtr driver,
 
     qemuDomainObjEnterMonitor(driver, vm);
     if (qemuMonitorDelDevice(priv->mon, detach->info.alias) < 0) {
-        qemuDomainObjExitMonitor(driver, vm);
+        if (qemuDomainObjExitMonitor(driver, vm) < 0)
+            goto cleanup;
         virDomainAuditDisk(vm, detach->src, NULL, "detach", false);
         goto cleanup;
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     rc = qemuDomainWaitForDeviceRemoval(vm);
     if (rc == 0 || rc == 1)
@@ -3219,17 +3232,20 @@ int qemuDomainDetachControllerDevice(virQEMUDriverPtr driver,
     qemuDomainObjEnterMonitor(driver, vm);
     if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE)) {
         if (qemuMonitorDelDevice(priv->mon, detach->info.alias)) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             goto cleanup;
         }
     } else {
         if (qemuMonitorRemovePCIDevice(priv->mon,
                                        &detach->info.addr.pci) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             goto cleanup;
         }
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     rc = qemuDomainWaitForDeviceRemoval(vm);
     if (rc == 0 || rc == 1)
@@ -3274,7 +3290,8 @@ qemuDomainDetachHostPCIDevice(virQEMUDriverPtr driver,
     } else {
         ret = qemuMonitorRemovePCIDevice(priv->mon, &detach->info->addr.pci);
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
 
     return ret;
 }
@@ -3303,7 +3320,8 @@ qemuDomainDetachHostUSBDevice(virQEMUDriverPtr driver,
 
     qemuDomainObjEnterMonitor(driver, vm);
     ret = qemuMonitorDelDevice(priv->mon, detach->info->alias);
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        ret = -1;
 
     return ret;
 }
@@ -3331,14 +3349,11 @@ qemuDomainDetachHostSCSIDevice(virQEMUDriverPtr driver,
     qemuDomainMarkDeviceForRemoval(vm, detach->info);
 
     qemuDomainObjEnterMonitor(driver, vm);
-    if (qemuMonitorDelDevice(priv->mon, detach->info->alias) < 0) {
-        qemuDomainObjExitMonitor(driver, vm);
-        goto cleanup;
-    }
-    qemuDomainObjExitMonitor(driver, vm);
-    ret = 0;
+    ret = qemuMonitorDelDevice(priv->mon, detach->info->alias);
+
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        return -1;
 
- cleanup:
     return ret;
 }
 
@@ -3374,7 +3389,8 @@ qemuDomainDetachThisHostDevice(virQEMUDriverPtr driver,
     }
 
     if (ret < 0) {
-        virDomainAuditHostdev(vm, detach, "detach", false);
+        if (virDomainObjIsActive(vm))
+            virDomainAuditHostdev(vm, detach, "detach", false);
     } else {
         int rc = qemuDomainWaitForDeviceRemoval(vm);
         if (rc == 0 || rc == 1)
@@ -3530,19 +3546,22 @@ qemuDomainDetachNetDevice(virQEMUDriverPtr driver,
     qemuDomainObjEnterMonitor(driver, vm);
     if (virQEMUCapsGet(priv->qemuCaps, QEMU_CAPS_DEVICE)) {
         if (qemuMonitorDelDevice(priv->mon, detach->info.alias) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditNet(vm, detach, NULL, "detach", false);
             goto cleanup;
         }
     } else {
         if (qemuMonitorRemovePCIDevice(priv->mon,
                                        &detach->info.addr.pci) < 0) {
-            qemuDomainObjExitMonitor(driver, vm);
+            if (qemuDomainObjExitMonitor(driver, vm) < 0)
+                goto cleanup;
             virDomainAuditNet(vm, detach, NULL, "detach", false);
             goto cleanup;
         }
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     rc = qemuDomainWaitForDeviceRemoval(vm);
     if (rc == 0 || rc == 1)
@@ -3709,10 +3728,12 @@ int qemuDomainDetachChrDevice(virQEMUDriverPtr driver,
 
     qemuDomainObjEnterMonitor(driver, vm);
     if (devstr && qemuMonitorDelDevice(priv->mon, tmpChr->info.alias) < 0) {
-        qemuDomainObjExitMonitor(driver, vm);
+        if (qemuDomainObjExitMonitor(driver, vm) < 0)
+            goto cleanup;
         goto cleanup;
     }
-    qemuDomainObjExitMonitor(driver, vm);
+    if (qemuDomainObjExitMonitor(driver, vm) < 0)
+        goto cleanup;
 
     rc = qemuDomainWaitForDeviceRemoval(vm);
     if (rc == 0 || rc == 1)

src/qemu/qemu_hotplug.h

@@ -107,9 +107,9 @@ virDomainChrDefPtr
 qemuDomainChrRemove(virDomainDefPtr vmdef,
                     virDomainChrDefPtr chr);
 
-void qemuDomainRemoveDevice(virQEMUDriverPtr driver,
-                            virDomainObjPtr vm,
-                            virDomainDeviceDefPtr dev);
+int qemuDomainRemoveDevice(virQEMUDriverPtr driver,
+                           virDomainObjPtr vm,
+                           virDomainDeviceDefPtr dev);
 
 bool qemuDomainSignalDeviceRemoval(virDomainObjPtr vm,
                                    const char *devAlias);

src/qemu/qemu_process.c

@@ -3629,8 +3629,10 @@ qemuProcessUpdateDevices(virQEMUDriverPtr driver,
     if ((tmp = old)) {
         while (*tmp) {
             if (!virStringArrayHasString(priv->qemuDevices, *tmp) &&
-                virDomainDefFindDevice(vm->def, *tmp, &dev, false) == 0)
-                qemuDomainRemoveDevice(driver, vm, &dev);
+                virDomainDefFindDevice(vm->def, *tmp, &dev, false) == 0 &&
+                qemuDomainRemoveDevice(driver, vm, &dev) < 0) {
+                goto cleanup;
+            }
             tmp++;
         }
     }