glx: guard swap-interval functions against destroyed drawables

The GLX specification says about glXDestroyPixmap:

    "The storage for the GLX pixmap will be freed when it is not current
     to any client."

So arguably, functions like glXSwapIntervalMESA can be called after
glXDestroyPixmap has been called for the currently bound GLXPixmap.
In that case, the GLXDRIDrawable no longer exists, and so we just skip
those calls.

Cc: 17.0 <mesa-stable@lists.freedesktop.org>
Reviewed-by: Marek Olšák <marek.olsak@amd.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>

diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
index 2d40f0ad458f10b5ef3608ee8a511c7d80d246fc..42a94f9f2424ff9518c96373e84823b551dccdc6 100644 (file)
--- a/src/glx/dri3_glx.c
+++ b/src/glx/dri3_glx.c
@@ -564,6 +564,8 @@ dri3_destroy_screen(struct glx_screen *base)
 static int
 dri3_set_swap_interval(__GLXDRIdrawable *pdraw, int interval)
 {
+   assert(pdraw != NULL);
+
    struct dri3_drawable *priv =  (struct dri3_drawable *) pdraw;
    GLint vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1;
    struct dri3_screen *psc = (struct dri3_screen *) priv->base.psc;
@@ -597,6 +599,8 @@ dri3_set_swap_interval(__GLXDRIdrawable *pdraw, int interval)
 static int
 dri3_get_swap_interval(__GLXDRIdrawable *pdraw)
 {
+   assert(pdraw != NULL);
+
    struct dri3_drawable *priv =  (struct dri3_drawable *) pdraw;
 
   return priv->swap_interval;

diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c
index 6c7bbfd5d1c0cf893868725ee30cbe2bf1af20dd..53c9f9ce2afa9ccfd6c30ac33bc3c231d0ac21ab 100644 (file)
--- a/src/glx/glxcmds.c
+++ b/src/glx/glxcmds.c
@@ -1761,7 +1761,11 @@ __glXSwapIntervalSGI(int interval)
           psc->driScreen->setSwapInterval) {
       __GLXDRIdrawable *pdraw =
         GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable);
-      psc->driScreen->setSwapInterval(pdraw, interval);
+      /* Simply ignore the command if the GLX drawable has been destroyed but
+       * the context is still bound.
+       */
+      if (pdraw)
+         psc->driScreen->setSwapInterval(pdraw, interval);
       return 0;
    }
 #endif
@@ -1807,7 +1811,14 @@ __glXSwapIntervalMESA(unsigned int interval)
       if (psc && psc->driScreen && psc->driScreen->setSwapInterval) {
          __GLXDRIdrawable *pdraw =
            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable);
-        return psc->driScreen->setSwapInterval(pdraw, interval);
+
+         /* Simply ignore the command if the GLX drawable has been destroyed but
+          * the context is still bound.
+          */
+         if (!pdraw)
+            return 0;
+
+         return psc->driScreen->setSwapInterval(pdraw, interval);
       }
    }
 #endif
@@ -1829,7 +1840,8 @@ __glXGetSwapIntervalMESA(void)
       if (psc && psc->driScreen && psc->driScreen->getSwapInterval) {
          __GLXDRIdrawable *pdraw =
            GetGLXDRIDrawable(gc->currentDpy, gc->currentDrawable);
-        return psc->driScreen->getSwapInterval(pdraw);
+         if (pdraw)
+            return psc->driScreen->getSwapInterval(pdraw);
       }
    }
 #endif