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Subject: Re: [PATCH 1/2] drm/i915: fix integer overflow in i915_gem_execbuffer2()
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From: Xi Wang <xi.wang@gmail.com>
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Date: Fri, 6 Apr 2012 09:46:46 -0400
Cc: Keith Packard <keithp@keithp.com>, Daniel Vetter <daniel.vetter@ffwll.ch>,
        linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
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To: Chris Wilson <chris@chris-wilson.co.uk>
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On Apr 6, 2012, at 9:36 AM, Chris Wilson wrote:

> 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.

On 32-bit platform?

- xi