[PATCH] tests/qtest/vhost-user-test: Fix memory leaks

[Thomas Huth]

Do not allocate resources in case we return early, and make sure
to free dest_cmdline at the end.

Reported-by: Euler Robot <address@hidden>
Reported-by: Pan Nengyuan <address@hidden>
Signed-off-by: Thomas Huth <address@hidden>
---
 Based on a similar patch by Pan Nengyuan:
  https://lists.gnu.org/archive/html/qemu-devel/2020-01/msg02183.html
 ... but that was causing some very weird problems in the gitlab CI
 for unknown reasons. This version now works fine in the gitlab CI.
  
 tests/qtest/vhost-user-test.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/tests/qtest/vhost-user-test.c b/tests/qtest/vhost-user-test.c
index 2324b964ad..9ee0f1e4fd 100644
--- a/tests/qtest/vhost-user-test.c
+++ b/tests/qtest/vhost-user-test.c
@@ -707,9 +707,9 @@ static void test_read_guest_mem(void *obj, void *arg, 
QGuestAllocator *alloc)
 static void test_migrate(void *obj, void *arg, QGuestAllocator *alloc)
 {
     TestServer *s = arg;
-    TestServer *dest = test_server_new("dest");
-    GString *dest_cmdline = g_string_new(qos_get_current_command_line());
-    char *uri = g_strdup_printf("%s%s", "unix:", dest->mig_path);
+    TestServer *dest;
+    GString *dest_cmdline;
+    char *uri;
     QTestState *to;
     GSource *source;
     QDict *rsp;
@@ -720,6 +720,10 @@ static void test_migrate(void *obj, void *arg, 
QGuestAllocator *alloc)
         return;
     }
 
+    dest = test_server_new("dest");
+    dest_cmdline = g_string_new(qos_get_current_command_line());
+    uri = g_strdup_printf("%s%s", "unix:", dest->mig_path);
+
     size = get_log_size(s);
     g_assert_cmpint(size, ==, (256 * 1024 * 1024) / (VHOST_LOG_PAGE * 8));
 
@@ -778,6 +782,7 @@ static void test_migrate(void *obj, void *arg, 
QGuestAllocator *alloc)
     qtest_quit(to);
     test_server_free(dest);
     g_free(uri);
+    g_string_free(dest_cmdline, true);
 }
 
 static void wait_for_rings_started(TestServer *s, size_t count)
-- 
2.18.1