media: v4l: ioctl: Sanitize num_planes before using it

The linked commit changed s_fmt/try_fmt to fail if num_planes is bogus.
This, however, is against the spec, which mandates drivers
to return a proper num_planes value, without an error.

Replace the num_planes check and instead clamp it to a sane value,
so we still make sure we don't overflow the planes array by accident.

Fixes: 9048b2e15b ("media: v4l: ioctl: Validate num_planes before using it")

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This commit is contained in:
Ezequiel Garcia 2019-02-18 05:25:42 -05:00 committed by Mauro Carvalho Chehab
parent 5f09bc8cc4
commit 14c8e80e68

View File

@ -1017,6 +1017,12 @@ static void v4l_sanitize_format(struct v4l2_format *fmt)
{
unsigned int offset;
/* Make sure num_planes is not bogus */
if (fmt->type == V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE ||
fmt->type == V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE)
fmt->fmt.pix_mp.num_planes = min_t(u32, fmt->fmt.pix_mp.num_planes,
VIDEO_MAX_PLANES);
/*
* The v4l2_pix_format structure has been extended with fields that were
* not previously required to be set to zero by applications. The priv
@ -1553,8 +1559,6 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
if (unlikely(!ops->vidioc_s_fmt_vid_cap_mplane))
break;
CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
if (p->fmt.pix_mp.num_planes > VIDEO_MAX_PLANES)
break;
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@ -1586,8 +1590,6 @@ static int v4l_s_fmt(const struct v4l2_ioctl_ops *ops,
if (unlikely(!ops->vidioc_s_fmt_vid_out_mplane))
break;
CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
if (p->fmt.pix_mp.num_planes > VIDEO_MAX_PLANES)
break;
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@ -1656,8 +1658,6 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
if (unlikely(!ops->vidioc_try_fmt_vid_cap_mplane))
break;
CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
if (p->fmt.pix_mp.num_planes > VIDEO_MAX_PLANES)
break;
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);
@ -1689,8 +1689,6 @@ static int v4l_try_fmt(const struct v4l2_ioctl_ops *ops,
if (unlikely(!ops->vidioc_try_fmt_vid_out_mplane))
break;
CLEAR_AFTER_FIELD(p, fmt.pix_mp.xfer_func);
if (p->fmt.pix_mp.num_planes > VIDEO_MAX_PLANES)
break;
for (i = 0; i < p->fmt.pix_mp.num_planes; i++)
CLEAR_AFTER_FIELD(&p->fmt.pix_mp.plane_fmt[i],
bytesperline);