From b5f508dd5226dc31eb191f0f4402d03ffcb63cac Mon Sep 17 00:00:00 2001
From: "Enrico Weigelt, metux IT consult" <info@metux.net>
Date: Thu, 10 Apr 2025 20:14:13 +0200
Subject: [PATCH] xwayland: use calloc() instead of malloc()

Using calloc() instead of malloc() as preventive measure, so there
never can be any hidden bugs or leaks due uninitialized memory.

The extra cost of using this compiler intrinsic should be practically
impossible to measure - in many cases a good compiler can even deduce
if certain areas really don't need to be zero'd (because they're written
to right after allocation) and create more efficient machine code.

The code pathes in question are pretty cold anyways, so it's probably
not worth even thinking about potential extra runtime costs.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
---
 hw/xwayland/xwayland-drm-lease.c  | 2 +-
 hw/xwayland/xwayland-glamor-gbm.c | 6 ++----
 hw/xwayland/xwayland-screen.c     | 2 +-
 hw/xwayland/xwayland-shm.c        | 3 +--
 4 files changed, 5 insertions(+), 8 deletions(-)

diff --git a/hw/xwayland/xwayland-drm-lease.c b/hw/xwayland/xwayland-drm-lease.c
index 30d363b59..d9a7bb8c1 100644
--- a/hw/xwayland/xwayland-drm-lease.c
+++ b/hw/xwayland/xwayland-drm-lease.c
@@ -455,7 +455,7 @@ xwl_screen_add_drm_lease_device(struct xwl_screen *xwl_screen, uint32_t id)
 {
     struct wp_drm_lease_device_v1 *lease_device = wl_registry_bind(
         xwl_screen->registry, id, &wp_drm_lease_device_v1_interface, 1);
-    struct xwl_drm_lease_device *device_data = malloc(sizeof(struct xwl_drm_lease_device));
+    struct xwl_drm_lease_device *device_data = calloc(1, sizeof(struct xwl_drm_lease_device));
 
     device_data->drm_lease_device = lease_device;
     device_data->xwl_screen = xwl_screen;
diff --git a/hw/xwayland/xwayland-glamor-gbm.c b/hw/xwayland/xwayland-glamor-gbm.c
index 05668b8e9..0d2a61edc 100644
--- a/hw/xwayland/xwayland-glamor-gbm.c
+++ b/hw/xwayland/xwayland-glamor-gbm.c
@@ -166,7 +166,6 @@ xwl_glamor_gbm_create_pixmap_for_bo(ScreenPtr screen, struct gbm_bo *bo,
                                     Bool implicit_modifier)
 {
     PixmapPtr pixmap;
-    struct xwl_pixmap *xwl_pixmap;
     struct xwl_screen *xwl_screen = xwl_screen_get(screen);
 #ifdef GBM_BO_FD_FOR_PLANE
     struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
@@ -218,7 +217,7 @@ xwl_glamor_gbm_create_pixmap_for_bo(ScreenPtr screen, struct gbm_bo *bo,
     for (plane = 0; plane < num_planes; plane++) fds[plane] = -1;
 #endif
 
-    xwl_pixmap = calloc(1, sizeof(*xwl_pixmap));
+    struct xwl_pixmap *xwl_pixmap = calloc(1, sizeof(struct xwl_pixmap));
     if (xwl_pixmap == NULL)
         return NULL;
 
@@ -717,7 +716,6 @@ xwl_dri3_open_client(ClientPtr client,
 {
     struct xwl_screen *xwl_screen = xwl_screen_get(screen);
     struct xwl_gbm_private *xwl_gbm = xwl_gbm_get(xwl_screen);
-    struct xwl_auth_state *state;
     drm_magic_t magic;
     int fd;
 
@@ -729,7 +727,7 @@ xwl_dri3_open_client(ClientPtr client,
         return Success;
     }
 
-    state = malloc(sizeof *state);
+    struct xwl_auth_state *state = calloc(1, sizeof(struct xwl_auth_state));
     if (state == NULL) {
         close(fd);
         return BadAlloc;
diff --git a/hw/xwayland/xwayland-screen.c b/hw/xwayland/xwayland-screen.c
index 308879213..d0d6fa67d 100644
--- a/hw/xwayland/xwayland-screen.c
+++ b/hw/xwayland/xwayland-screen.c
@@ -524,7 +524,7 @@ registry_global(void *data, struct wl_registry *registry, uint32_t id,
     }
     else if (strcmp(interface, wp_drm_lease_device_v1_interface.name) == 0) {
         if (xwl_screen->screen->root == NULL) {
-            struct xwl_queued_drm_lease_device *queued = malloc(sizeof(struct xwl_queued_drm_lease_device));
+            struct xwl_queued_drm_lease_device *queued = calloc(1, sizeof(struct xwl_queued_drm_lease_device));
             queued->id = id;
             xorg_list_append(&queued->link, &xwl_screen->queued_drm_lease_devices);
         } else {
diff --git a/hw/xwayland/xwayland-shm.c b/hw/xwayland/xwayland-shm.c
index faca5224e..929ca7450 100644
--- a/hw/xwayland/xwayland-shm.c
+++ b/hw/xwayland/xwayland-shm.c
@@ -128,7 +128,6 @@ os_create_anonymous_file(off_t size)
 {
     static const char template[] = "/xwayland-shared-XXXXXX";
     const char *path;
-    char *name;
     int fd;
     int ret;
 
@@ -151,7 +150,7 @@ os_create_anonymous_file(off_t size)
             return -1;
         }
 
-        name = malloc(strlen(path) + sizeof(template));
+        char *name = calloc(1, strlen(path) + sizeof(template));
         if (!name)
             return -1;