[PATCH] drm: Perform ioctl command validation on the stored kernel values

[Dave Airlie]

> ioctl cmd, and for example trinity likes to fuzz those bits to create
> conflicting commands. So instead of relying upon userspace to pass along
> the correct IN/OUT flags for the ioctl, use the flags as expected by the
> kernel.
>
> This does have a side-effect that NULL pointers can not be substituted
> by userspace in place of a struct. This feature was not being used by
> any driver, but instead exposed all of the command handlers to a user
> triggerable OOPS.
>
> Reported-by: Tommi Rantala <tt.rantala at gmail.com>
> Link: http://lkml.kernel.org/r/CA+ydwtpuBvbwxbt-tdgPUvj1EU7itmCHo_2B3w13HkD5+jWKow@mail.gmail.com
> Signed-off-by: Tommi Rantala <tt.rantala at gmail.com>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

Applied thanks.

Dave.