[PULL v2 3/5] tests/9pfs: Fix leak of local_test_path

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

From: Greg Kurz <groug@kaod.org>

local_test_path is allocated in virtio_9p_create_local_test_dir() to hold the path
of the temporary directory. It should be freed in virtio_9p_remove_local_test_dir()
when the temporary directory is removed. Clarify the lifecycle of local_test_path
while here.

Based-on: <f6602123c6f7d0d593466231b04fba087817abbd.1642879848.git.qemu_oss@crudebyte.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20220201151508.190035-2-groug@kaod.org>
Reviewed-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
---
 tests/qtest/libqos/virtio-9p.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tests/qtest/libqos/virtio-9p.c b/tests/qtest/libqos/virtio-9p.c
index ef96ef006a..5d18e5eae5 100644
--- a/tests/qtest/libqos/virtio-9p.c
+++ b/tests/qtest/libqos/virtio-9p.c
@@ -39,8 +39,13 @@ static char *concat_path(const char* a, const char* b)
 
 void virtio_9p_create_local_test_dir(void)
 {
+    g_assert(local_test_path == NULL);
     struct stat st;
     char *pwd = g_get_current_dir();
+    /*
+     * template gets cached into local_test_path and freed in
+     * virtio_9p_remove_local_test_dir().
+     */
     char *template = concat_path(pwd, "qtest-9p-local-XXXXXX");
 
     local_test_path = mkdtemp(template);
@@ -66,6 +71,8 @@ void virtio_9p_remove_local_test_dir(void)
         /* ignore error, dummy check to prevent compiler error */
     }
     g_free(cmd);
+    g_free(local_test_path);
+    local_test_path = NULL;
 }
 
 char *virtio_9p_test_path(const char *path)
-- 
2.20.1