Fixed bug 5007 - Segfault in KMSDRM_VideoQuit() on Raspberry Pi Zero with no display attached

Charles Huber

This patch fixes the segfault on my Pi, though the valid display index range reported by the CHECK_DISPLAY_INDEX() macro in src/video/SDL_video.c is a little weird:

$ SDL_VIDEO_EGL_DRIVER=libEGL.so SDL_VIDEO_GL_DRIVER=libGLESv2.so ./a.out
SDL_Init(): displayIndex must be in the range 0 - -1

src/video/kmsdrm/SDL_kmsdrmvideo.c

@@ -650,7 +650,7 @@ KMSDRM_VideoQuit(_THIS)
     viddata->num_windows = 0;
 
     /* Restore saved CRTC settings */
-    if (viddata->drm_fd >= 0 && dispdata->conn && dispdata->saved_crtc) {
+    if (viddata->drm_fd >= 0 && dispdata && dispdata->conn && dispdata->saved_crtc) {
         drmModeConnector *conn = dispdata->conn;
         drmModeCrtc *crtc = dispdata->saved_crtc;
 
@@ -661,11 +661,11 @@ KMSDRM_VideoQuit(_THIS)
             SDL_LogWarn(SDL_LOG_CATEGORY_VIDEO, "Could not restore original CRTC mode");
         }
     }
-    if (dispdata->conn) {
+    if (dispdata && dispdata->conn) {
         KMSDRM_drmModeFreeConnector(dispdata->conn);
         dispdata->conn = NULL;
     }
-    if (dispdata->saved_crtc) {
+    if (dispdata && dispdata->saved_crtc) {
         KMSDRM_drmModeFreeCrtc(dispdata->saved_crtc);
         dispdata->saved_crtc = NULL;
     }