From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: [PATCH 1/2] drm/i915: fix integer overflow in
	i915_gem_execbuffer2()
Date: Fri, 06 Apr 2012 14:36:40 +0100
Message-ID: <1333719431_271283@CP5-2952>
References: <1333717099-32679-1-git-send-email-xi.wang@gmail.com>
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To: Xi Wang <xi.wang@gmail.com>, Keith Packard <keithp@keithp.com>, Daniel Vetter <daniel.vetter@ffwll.ch>
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On Fri,  6 Apr 2012 08:58:18 -0400, Xi Wang <xi.wang@gmail.com> wrote:
> A large args->buffer_count from userspace may overflow the allocation
> size, leading to out-of-bounds access.
> 
> Use kmalloc_array() to avoid that.

I can safely say that exec list larger than 4GiB is going to be an
illegal operation and would rather the ioctl failed outright with
EINVAL.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre