Re: [Intel-gfx] [PATCH] drm/i915: Sanity check incoming ioctl datafor a NULL pointer

From: Chris Wilson
Date: Sun Mar 17 2013 - 17:41:18 EST


On Sun, Mar 17, 2013 at 08:50:03PM +0100, Daniel Vetter wrote:
> On Sat, Mar 16, 2013 at 11:19 AM, Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> wrote:
> > If *userspace* doesn't request either IOC_IN | IOC_OUT in their ioctl
> > command (which are seperate from the ioctl number), then kdata is set to
> > NULL.
>
> Doesn't that mean that we need these checks everywhere? Or at least a
> fixup in drm core proper?

That's my conclusion. We either add a flag to ask drm_ioctl to prevent
passing NULL pointers (as the existing behaviour may be useful
somewhere, and I have not checked all callees) or saturate our callbacks
with NULL checks.
-Chris
--
Chris Wilson, Intel Open Source Technology Centre
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