Re: [PATCH] drm/i915: bounds check execbuffer relocations

From: Chris Wilson
Date: Mon Mar 11 2013 - 16:53:04 EST


On Mon, Mar 11, 2013 at 12:27:16PM -0700, Kees Cook wrote:
> It is possible to wrap the counter used to allocate the buffer for
> relocation copies. This could lead to heap writing overflows.

Seems a sensible check, just in the wrong location. You need to do the
checking upfront in validate_exec_list() so that the error condition is
always hit and that the limits are applied consistently to all
execbuffers.
-Chris

--
Chris Wilson, Intel Open Source Technology Centre
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