vulkan/wsi/x11: add null pointer check for the has_dri3_v1_2 test

This fixes a crash (ver_reply is NULL) when DISPLAY points to
a remote display.

Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/6040
Signed-off-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Adam Jackson <ajax@redhat.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15469>

diff --git a/src/vulkan/wsi/wsi_common_x11.c b/src/vulkan/wsi/wsi_common_x11.c
index 85a66a9..6b09d73 100644 (file)
--- a/src/vulkan/wsi/wsi_common_x11.c
+++ b/src/vulkan/wsi/wsi_common_x11.c
@@ -246,7 +246,7 @@ wsi_x11_connection_create(struct wsi_device *wsi_dev,
 
       ver_cookie = xcb_dri3_query_version(conn, 1, 2);
       ver_reply = xcb_dri3_query_version_reply(conn, ver_cookie, NULL);
-      has_dri3_v1_2 =
+      has_dri3_v1_2 = ver_reply != NULL &&
          (ver_reply->major_version > 1 || ver_reply->minor_version >= 2);
       free(ver_reply);
    }