Re: Patch "[media] videobuf2-v4l2: Verify planes array in buffer dequeueing" has been added to the 4.4-stable tree

[Greg KH <gregkh@linuxfoundation.org>]

Oops, nope, this patch breaks the build on 4.4-stable,
.verify_planes_array is not a member function here :(

If this is needed, please provide a working backport.

thanks,

greg k-h


On Sun, May 01, 2016 at 05:02:10PM -0700, gregkh@linuxfoundation.org wrote:
> 
> This is a note to let you know that I've just added the patch titled
> 
>     [media] videobuf2-v4l2: Verify planes array in buffer dequeueing
> 
> to the 4.4-stable tree which can be found at:
>     http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
> 
> The filename of the patch is:
>      videobuf2-v4l2-verify-planes-array-in-buffer-dequeueing.patch
> and it can be found in the queue-4.4 subdirectory.
> 
> If you, or anyone else, feels it should not be added to the stable tree,
> please let <stable@vger.kernel.org> know about it.
> 
> 
> >From 2c1f6951a8a82e6de0d82b1158b5e493fc6c54ab Mon Sep 17 00:00:00 2001
> From: Sakari Ailus <sakari.ailus@linux.intel.com>
> Date: Sun, 3 Apr 2016 16:31:03 -0300
> Subject: [media] videobuf2-v4l2: Verify planes array in buffer dequeueing
> 
> From: Sakari Ailus <sakari.ailus@linux.intel.com>
> 
> commit 2c1f6951a8a82e6de0d82b1158b5e493fc6c54ab upstream.
> 
> When a buffer is being dequeued using VIDIOC_DQBUF IOCTL, the exact buffer
> which will be dequeued is not known until the buffer has been removed from
> the queue. The number of planes is specific to a buffer, not to the queue.
> 
> This does lead to the situation where multi-plane buffers may be requested
> and queued with n planes, but VIDIOC_DQBUF IOCTL may be passed an argument
> struct with fewer planes.
> 
> __fill_v4l2_buffer() however uses the number of planes from the dequeued
> videobuf2 buffer, overwriting kernel memory (the m.planes array allocated
> in video_usercopy() in v4l2-ioctl.c)  if the user provided fewer
> planes than the dequeued buffer had. Oops!
> 
> Fixes: b0e0e1f83de3 ("[media] media: videobuf2: Prepare to divide videobuf2")
> 
> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
> Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> 
> ---
>  drivers/media/v4l2-core/videobuf2-v4l2.c |    6 ++++++
>  1 file changed, 6 insertions(+)
> 
> --- a/drivers/media/v4l2-core/videobuf2-v4l2.c
> +++ b/drivers/media/v4l2-core/videobuf2-v4l2.c
> @@ -67,6 +67,11 @@ static int __verify_planes_array(struct
>  	return 0;
>  }
>  
> +static int __verify_planes_array_core(struct vb2_buffer *vb, const void *pb)
> +{
> +	return __verify_planes_array(vb, pb);
> +}
> +
>  /**
>   * __verify_length() - Verify that the bytesused value for each plane fits in
>   * the plane length and that the data offset doesn't exceed the bytesused value.
> @@ -432,6 +437,7 @@ static int __fill_vb2_buffer(struct vb2_
>  }
>  
>  static const struct vb2_buf_ops v4l2_buf_ops = {
> +	.verify_planes_array	= __verify_planes_array_core,
>  	.fill_user_buffer	= __fill_v4l2_buffer,
>  	.fill_vb2_buffer	= __fill_vb2_buffer,
>  	.set_timestamp		= __set_timestamp,
> 
> 
> Patches currently in stable-queue which might be from sakari.ailus@linux.intel.com are
> 
> queue-4.4/videobuf2-v4l2-verify-planes-array-in-buffer-dequeueing.patch