conf: Perform error checking in virDomainDeviceInfoFormat()

virXMLFormatElement() might fail, but we were not checking
its return value.

Fixing this requires us to change virDomainDeviceInfoFormat()
so that it can report an error back to the caller.

Introduced-by: 0d6b8733
Spotted-by: Coverity
Reported-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NAndrea Bolognani <abologna@redhat.com>
Reviewed-by: NPavel Hrdina <phrdina@redhat.com>

src/conf/domain_conf.c

@@ -6418,13 +6418,14 @@ virDomainVirtioOptionsFormat(virBufferPtr buf,
 }
 
 
-static void ATTRIBUTE_NONNULL(2)
+static int ATTRIBUTE_NONNULL(2)
 virDomainDeviceInfoFormat(virBufferPtr buf,
                           virDomainDeviceInfoPtr info,
                           unsigned int flags)
 {
     virBuffer attrBuf = VIR_BUFFER_INITIALIZER;
     virBuffer childBuf = VIR_BUFFER_INITIALIZER;
+    int ret = -1;
 
     if ((flags & VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT) && info->bootIndex) {
         virBufferAsprintf(buf, "<boot order='%u'", info->bootIndex);
@@ -6467,8 +6468,11 @@ virDomainDeviceInfoFormat(virBufferPtr buf,
     }
 
     if (info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_NONE ||
-        info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_S390)
-        return;
+        info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_VIRTIO_S390) {
+        /* We're done here */
+        ret = 0;
+        goto cleanup;
+    }
 
     virBufferAsprintf(&attrBuf, " type='%s'",
                       virDomainDeviceAddressTypeToString(info->type));
@@ -6562,10 +6566,16 @@ virDomainDeviceInfoFormat(virBufferPtr buf,
         break;
     }
 
-    virXMLFormatElement(buf, "address", &attrBuf, &childBuf);
+    if (virXMLFormatElement(buf, "address", &attrBuf, &childBuf) < 0)
+        goto cleanup;
+
+    ret = 0;
 
+ cleanup:
     virBufferFreeAndReset(&attrBuf);
     virBufferFreeAndReset(&childBuf);
+
+    return ret;
 }
 
 static int
@@ -24299,8 +24309,10 @@ virDomainDiskDefFormat(virBufferPtr buf,
     if (def->src->encryption && !def->src->encryptionInherited &&
         virStorageEncryptionFormat(buf, def->src->encryption) < 0)
         return -1;
-    virDomainDeviceInfoFormat(buf, &def->info,
-                              flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT);
+    if (virDomainDeviceInfoFormat(buf, &def->info,
+                                  flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT) < 0) {
+        return -1;
+    }
 
     if (virDomainDiskDefFormatPrivateData(buf, def, flags, xmlopt) < 0)
         return -1;
@@ -24475,7 +24487,8 @@ virDomainControllerDefFormat(virBufferPtr buf,
 
     virDomainControllerDriverFormat(&childBuf, def);
 
-    virDomainDeviceInfoFormat(&childBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (def->type == VIR_DOMAIN_CONTROLLER_TYPE_PCI &&
         def->opts.pciopts.pcihole64) {
@@ -24613,7 +24626,8 @@ virDomainFSDefFormat(virBufferPtr buf,
     if (def->readonly)
         virBufferAddLit(buf, "<readonly/>\n");
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (def->space_hard_limit)
         virBufferAsprintf(buf, "<space_hard_limit unit='bytes'>"
@@ -25412,9 +25426,11 @@ virDomainNetDefFormat(virBufferPtr buf,
 
     virDomainNetDefCoalesceFormatXML(buf, def->coalesce);
 
-    virDomainDeviceInfoFormat(buf, &def->info,
-                              flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT
-                              | VIR_DOMAIN_DEF_FORMAT_ALLOW_ROM);
+    if (virDomainDeviceInfoFormat(buf, &def->info,
+                                  flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT
+                                  | VIR_DOMAIN_DEF_FORMAT_ALLOW_ROM) < 0) {
+        return -1;
+    }
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</interface>\n");
@@ -25723,7 +25739,8 @@ virDomainChrDefFormat(virBufferPtr buf,
     if (virDomainChrTargetDefFormat(buf, def, flags) < 0)
         return -1;
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        return -1;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAsprintf(buf, "</%s>\n", elementName);
@@ -25772,7 +25789,8 @@ virDomainSmartcardDefFormat(virBufferPtr buf,
                        _("unexpected smartcard type %d"), def->type);
         goto cleanup;
     }
-    virDomainDeviceInfoFormat(&childBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childBuf) < 0)
         goto cleanup;
@@ -25843,7 +25861,8 @@ virDomainTPMDefFormat(virBufferPtr buf,
         break;
     }
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        return -1;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</tpm>\n");
@@ -25873,7 +25892,8 @@ virDomainSoundDefFormat(virBufferPtr buf,
     for (i = 0; i < def->ncodecs; i++)
         virDomainSoundCodecDefFormat(&childBuf, def->codecs[i]);
 
-    virDomainDeviceInfoFormat(&childBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childBuf) < 0)
         goto cleanup;
@@ -25922,7 +25942,8 @@ virDomainMemballoonDefFormat(virBufferPtr buf,
     if (def->period)
         virBufferAsprintf(&childrenBuf, "<stats period='%i'/>\n", def->period);
 
-    virDomainDeviceInfoFormat(&childrenBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childrenBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (def->virtio) {
         virBuffer driverBuf = VIR_BUFFER_INITIALIZER;
@@ -25965,7 +25986,8 @@ virDomainNVRAMDefFormat(virBufferPtr buf,
 {
     virBufferAddLit(buf, "<nvram>\n");
     virBufferAdjustIndent(buf, 2);
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        return -1;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</nvram>\n");
@@ -25998,7 +26020,8 @@ virDomainWatchdogDefFormat(virBufferPtr buf,
         goto cleanup;
     }
 
-    virDomainDeviceInfoFormat(&childBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childBuf) < 0)
         goto cleanup;
@@ -26035,7 +26058,8 @@ static int virDomainPanicDefFormat(virBufferPtr buf,
                           virDomainPanicModelTypeToString(def->model));
 
     virBufferSetChildIndent(&childrenBuf, buf);
-    virDomainDeviceInfoFormat(&childrenBuf, &def->info, 0);
+    if (virDomainDeviceInfoFormat(&childrenBuf, &def->info, 0) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childrenBuf) < 0)
         goto cleanup;
@@ -26087,7 +26111,8 @@ virDomainShmemDefFormat(virBufferPtr buf,
         virBufferAddLit(buf, "/>\n");
     }
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        return -1;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</shmem>\n");
@@ -26144,7 +26169,8 @@ virDomainRNGDefFormat(virBufferPtr buf,
         virBufferAddLit(buf, "/>\n");
     }
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        goto cleanup;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</rng>\n");
@@ -26271,7 +26297,8 @@ virDomainMemoryDefFormat(virBufferPtr buf,
 
     virDomainMemoryTargetDefFormat(buf, def);
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        return -1;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</memory>\n");
@@ -26348,7 +26375,8 @@ virDomainVideoDefFormat(virBufferPtr buf,
         virBufferAddLit(buf, "/>\n");
     }
 
-    virDomainDeviceInfoFormat(buf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(buf, &def->info, flags) < 0)
+        goto cleanup;
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</video>\n");
@@ -26404,7 +26432,8 @@ virDomainInputDefFormat(virBufferPtr buf,
         virBufferAddLit(&childbuf, "/>\n");
     }
     virBufferEscapeString(&childbuf, "<source evdev='%s'/>\n", def->source.evdev);
-    virDomainDeviceInfoFormat(&childbuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childbuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childbuf) < 0)
         goto cleanup;
@@ -27004,9 +27033,11 @@ virDomainHostdevDefFormat(virBufferPtr buf,
     if (def->shareable)
         virBufferAddLit(buf, "<shareable/>\n");
 
-    virDomainDeviceInfoFormat(buf, def->info,
-                              flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT
-                              | VIR_DOMAIN_DEF_FORMAT_ALLOW_ROM);
+    if (virDomainDeviceInfoFormat(buf, def->info,
+                                  flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT
+                                  | VIR_DOMAIN_DEF_FORMAT_ALLOW_ROM) < 0) {
+        return -1;
+    }
 
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</hostdev>\n");
@@ -27032,8 +27063,10 @@ virDomainRedirdevDefFormat(virBufferPtr buf,
     if (virDomainChrSourceDefFormat(buf, def->source, flags) < 0)
         return -1;
 
-    virDomainDeviceInfoFormat(buf, &def->info,
-                              flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT);
+    if (virDomainDeviceInfoFormat(buf, &def->info,
+                                  flags | VIR_DOMAIN_DEF_FORMAT_ALLOW_BOOT) < 0) {
+        return -1;
+    }
     virBufferAdjustIndent(buf, -2);
     virBufferAddLit(buf, "</redirdev>\n");
     return 0;
@@ -27095,7 +27128,8 @@ virDomainHubDefFormat(virBufferPtr buf,
         goto cleanup;
     }
 
-    virDomainDeviceInfoFormat(&childBuf, &def->info, flags);
+    if (virDomainDeviceInfoFormat(&childBuf, &def->info, flags) < 0)
+        goto cleanup;
 
     if (virBufferCheckError(&childBuf) < 0)
         goto cleanup;
@@ -27816,7 +27850,8 @@ virDomainVsockDefFormat(virBufferPtr buf,
     if (virXMLFormatElement(&childBuf, "cid", &cidAttrBuf, NULL) < 0)
         goto cleanup;
 
-    virDomainDeviceInfoFormat(&childBuf, &vsock->info, 0);
+    if (virDomainDeviceInfoFormat(&childBuf, &vsock->info, 0) < 0)
+        goto cleanup;
 
     if (virXMLFormatElement(buf, "vsock", &attrBuf, &childBuf) < 0)
         goto cleanup;