qemu: Free persistent def inside qemuMigrationCookieFree

Creating a copy of the definition we want to add in a migration cookie
makes the code cleaner and less prone to memory leaks or double free
errors.
Signed-off-by: NJiri Denemark <jdenemar@redhat.com>

src/qemu/qemu_migration.c

@@ -3617,11 +3617,13 @@ qemuMigrationRun(virQEMUDriverPtr driver,
         if (persist_xml) {
             persistDef = qemuMigrationPrepareDef(driver, persist_xml,
                                                  NULL, NULL);
-            if (!persistDef)
-                goto cleanup;
         } else {
-            persistDef = vm->newDef;
+            persistDef = qemuDomainDefCopy(driver, vm->newDef,
+                                           VIR_DOMAIN_XML_SECURE |
+                                           VIR_DOMAIN_XML_MIGRATABLE);
         }
+        if (!persistDef)
+            goto cleanup;
     }
 
     mig = qemuMigrationEatCookie(driver, vm, cookiein, cookieinlen,
@@ -3868,13 +3870,12 @@ qemuMigrationRun(virQEMUDriverPtr driver,
                    QEMU_MIGRATION_COOKIE_STATS;
 
     if (ret == 0 &&
-        (qemuMigrationCookieAddPersistent(mig, persistDef) < 0 ||
+        (qemuMigrationCookieAddPersistent(mig, &persistDef) < 0 ||
          qemuMigrationBakeCookie(mig, driver, vm, cookieout,
                                  cookieoutlen, cookieFlags) < 0)) {
         VIR_WARN("Unable to encode migration cookie");
     }
 
-    if (persistDef != vm->newDef)
     virDomainDefFree(persistDef);
     qemuMigrationCookieFree(mig);
 
@@ -5365,10 +5366,7 @@ qemuMigrationFinish(virQEMUDriverPtr driver,
         qemuMonitorSetDomainLog(priv->mon, NULL, NULL, NULL);
     VIR_FREE(priv->origname);
     virDomainObjEndAPI(&vm);
-    if (mig) {
-        virDomainDefFree(qemuMigrationCookieGetPersistent(mig));
     qemuMigrationCookieFree(mig);
-    }
     if (orig_err) {
         virSetError(orig_err);
         virFreeError(orig_err);

src/qemu/qemu_migration_cookie.c

@@ -99,6 +99,7 @@ qemuMigrationCookieFree(qemuMigrationCookiePtr mig)
         return;
 
     qemuMigrationCookieGraphicsFree(mig->graphics);
+    virDomainDefFree(mig->persistent);
     qemuMigrationCookieNetworkFree(mig->network);
     qemuMigrationCookieNBDFree(mig->nbd);
 
@@ -385,7 +386,7 @@ qemuMigrationCookieAddLockstate(qemuMigrationCookiePtr mig,
 
 int
 qemuMigrationCookieAddPersistent(qemuMigrationCookiePtr mig,
-                                 virDomainDefPtr def)
+                                 virDomainDefPtr *def)
 {
     if (mig->flags & QEMU_MIGRATION_COOKIE_PERSISTENT) {
         virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -393,10 +394,11 @@ qemuMigrationCookieAddPersistent(qemuMigrationCookiePtr mig,
         return -1;
     }
 
-    if (!def)
+    if (!def || !*def)
         return 0;
 
-    mig->persistent = def;
+    mig->persistent = *def;
+    *def = NULL;
     mig->flags |= QEMU_MIGRATION_COOKIE_PERSISTENT;
     mig->flagsMandatory |= QEMU_MIGRATION_COOKIE_PERSISTENT;
     return 0;

src/qemu/qemu_migration_cookie.h

@@ -145,7 +145,7 @@ qemuMigrationCookieFree(qemuMigrationCookiePtr mig);
 
 int
 qemuMigrationCookieAddPersistent(qemuMigrationCookiePtr mig,
-                                 virDomainDefPtr def);
+                                 virDomainDefPtr *def);
 
 virDomainDefPtr
 qemuMigrationCookieGetPersistent(qemuMigrationCookiePtr mig);