From 7e581780603d6b15291d032efdeeca77f969e0ba Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Thu, 24 Jun 2010 12:24:58 +0100 Subject: glx: Prevent NULL context deref in __glXGetDrawable() (bug 29184) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit During a SwapBuffers request, we may end up querying an unknown drawable outside of an active context, and so need to report this error prior to attempting to dereference the NULL context. Also fixes: [Bug 29184] glXSwapBuffers with no GLX context crashes X. https://bugs.freedesktop.org/show_bug.cgi?id=29184 Signed-off-by: Chris Wilson Cc: Kristian Høgsberg Reviewed-by: Adam Jackson Signed-off-by: Keith Packard --- glx/glxcmds.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'glx') diff --git a/glx/glxcmds.c b/glx/glxcmds.c index 9e5b2139e..8d13c1509 100644 --- a/glx/glxcmds.c +++ b/glx/glxcmds.c @@ -491,6 +491,13 @@ __glXGetDrawable(__GLXcontext *glxc, GLXDrawable drawId, ClientPtr client, return pGlxDraw; } + /* No active context and an unknown drawable, bail. */ + if (glxc == NULL) { + client->errorValue = drawId; + *error = BadMatch; + return NULL; + } + /* The drawId wasn't a GLX drawable. Make sure it's a window and * create a GLXWindow for it. Check that the drawable screen * matches the context screen and that the context fbconfig is -- cgit v1.2.3