[Mesa-dev] [PATCH 2/2] glx: clean-up __glXInitialize handling

[Emil Velikov]

Consistently check for the function return status to prevent
null ptr deref, and stop calling it without a purpose.

Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>
---
 src/glx/dri2_glx.c  | 21 +++++++++++++++------
 src/glx/dri3_glx.c  |  8 ++++----
 src/glx/drisw_glx.c |  5 +----
 3 files changed, 20 insertions(+), 14 deletions(-)

diff --git a/src/glx/dri2_glx.c b/src/glx/dri2_glx.c
index 298e771..c84fda9 100644
--- a/src/glx/dri2_glx.c
+++ b/src/glx/dri2_glx.c
@@ -749,7 +749,8 @@ unsigned dri2GetSwapEventType(Display* dpy, XID drawable)
       struct glx_display *glx_dpy = __glXInitialize(dpy);
       __GLXDRIdrawable *pdraw;
       pdraw = dri2GetGlxDrawableFromXDrawableId(dpy, drawable);
-      if (!pdraw || !(pdraw->eventMask & GLX_BUFFER_SWAP_COMPLETE_INTEL_MASK))
+
+      if (!glx_dpy || !pdraw || !(pdraw->eventMask & GLX_BUFFER_SWAP_COMPLETE_INTEL_MASK))
          return 0;
       return glx_dpy->codes->first_event + GLX_BufferSwapComplete;
 }
@@ -830,10 +831,14 @@ dri2SwapBuffers(__GLXDRIdrawable *pdraw, int64_t target_msc, int64_t divisor,
     struct dri2_drawable *priv = (struct dri2_drawable *) pdraw;
     struct glx_display *dpyPriv = __glXInitialize(priv->base.psc->dpy);
     struct dri2_screen *psc = (struct dri2_screen *) priv->base.psc;
-    struct dri2_display *pdp =
-	(struct dri2_display *)dpyPriv->dri2Display;
+    struct dri2_display *pdp;
     int64_t ret = 0;
 
+    if (dpyPriv == NULL)
+        return;
+
+    pdp = (struct dri2_display *) dpyPriv->dri2Display;
+
     /* Check we have the right attachments */
     if (!priv->have_back)
 	return ret;
@@ -1048,11 +1053,10 @@ dri2_release_tex_image(Display * dpy, GLXDrawable drawable, int buffer)
    struct glx_context *gc = __glXGetCurrentContext();
    struct dri2_context *pcp = (struct dri2_context *) gc;
    __GLXDRIdrawable *base = GetGLXDRIDrawable(dpy, drawable);
-   struct glx_display *dpyPriv = __glXInitialize(dpy);
    struct dri2_drawable *pdraw = (struct dri2_drawable *) base;
    struct dri2_screen *psc;
 
-   if (dpyPriv != NULL && pdraw != NULL) {
+   if (pdraw != NULL) {
       psc = (struct dri2_screen *) base->psc;
 
       if (psc->texBuffer->base.version >= 3 &&
@@ -1359,9 +1363,14 @@ _X_HIDDEN __GLXDRIdrawable *
 dri2GetGlxDrawableFromXDrawableId(Display *dpy, XID id)
 {
    struct glx_display *d = __glXInitialize(dpy);
-   struct dri2_display *pdp = (struct dri2_display *) d->dri2Display;
+   struct dri2_display *pdp;
    __GLXDRIdrawable *pdraw;
 
+   if (d == NULL)
+      return NULL;
+
+   pdp = (struct dri2_display *) d->dri2Display;
+
    if (__glxHashLookup(pdp->dri2Hash, id, (void *) &pdraw) == 0)
       return pdraw;
 
diff --git a/src/glx/dri3_glx.c b/src/glx/dri3_glx.c
index 4cde9ef..93c5567 100644
--- a/src/glx/dri3_glx.c
+++ b/src/glx/dri3_glx.c
@@ -302,9 +302,13 @@ dri3_create_drawable(struct glx_screen *base, XID xDrawable,
 {
    struct dri3_drawable *pdraw;
    struct dri3_screen *psc = (struct dri3_screen *) base;
+   struct glx_display *dpyPriv = __glXInitialize(psc->base.dpy);
    __GLXDRIconfigPrivate *config = (__GLXDRIconfigPrivate *) config_base;
    GLint vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1;
 
+   if (dpyPriv == NULL)
+      return NULL;
+
    pdraw = calloc(1, sizeof(*pdraw));
    if (!pdraw)
       return NULL;
@@ -335,8 +339,6 @@ dri3_create_drawable(struct glx_screen *base, XID xDrawable,
 
    dri3_update_num_back(pdraw);
 
-   (void) __glXInitialize(psc->base.dpy);
-
    /* Create a new drawable */
    pdraw->driDrawable =
       (*psc->image_driver->createNewDrawable) (psc->driScreen,
@@ -694,8 +696,6 @@ dri3_flush_front_buffer(__DRIdrawable *driDrawable, void *loaderPrivate)
 
    psc = (struct dri3_screen *) pdraw->base.psc;
 
-   (void) __glXInitialize(psc->base.dpy);
-
    gc = __glXGetCurrentContext();
 
    dri3_flush(psc, pdraw, __DRI2_FLUSH_DRAWABLE, __DRI2_THROTTLE_FLUSHFRONT);
diff --git a/src/glx/drisw_glx.c b/src/glx/drisw_glx.c
index 751626b..8c96a9c 100644
--- a/src/glx/drisw_glx.c
+++ b/src/glx/drisw_glx.c
@@ -316,8 +316,6 @@ drisw_bind_tex_image(Display * dpy,
    struct drisw_drawable *pdraw = (struct drisw_drawable *) base;
    struct drisw_screen *psc;
 
-   __glXInitialize(dpy);
-
    if (pdraw != NULL) {
       psc = (struct drisw_screen *) base->psc;
 
@@ -345,11 +343,10 @@ drisw_release_tex_image(Display * dpy, GLXDrawable drawable, int buffer)
    struct glx_context *gc = __glXGetCurrentContext();
    struct drisw_context *pcp = (struct drisw_context *) gc;
    __GLXDRIdrawable *base = GetGLXDRIDrawable(dpy, drawable);
-   struct glx_display *dpyPriv = __glXInitialize(dpy);
    struct drisw_drawable *pdraw = (struct drisw_drawable *) base;
    struct drisw_screen *psc;
 
-   if (dpyPriv != NULL && pdraw != NULL) {
+   if (pdraw != NULL) {
       psc = (struct drisw_screen *) base->psc;
 
       if (!psc->texBuffer)
-- 
1.9.0