media: v4l: ioctl: Validate num_planes before using it

The for loop to reset the memory of the plane reserved fields runs over
num_planes provided by the user without validating it. Ensure num_planes
is no more than VIDEO_MAX_PLANES before the loop.

Fixes: 4e1e0eb0e074 ("media: v4l2-ioctl: Zero v4l2_plane_pix_format reserved fields")

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
index ca85c3a9a7b9..44bc7c4f1c11 100644
--- a/drivers/media/v4l2-core/v4l2-ioctl.c
+++ b/drivers/media/v4l2-core/v4l2-ioctl.c
@@ -1551,6 +1551,8 @@ 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);
@@ -1582,6 +1584,8 @@ 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);
@@ -1650,6 +1654,8 @@ 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);
@@ -1681,6 +1687,8 @@ 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);