From 14c8e80e68695c2b9342112c39263a79e0963461 Mon Sep 17 00:00:00 2001 From: Ezequiel Garcia Date: Mon, 18 Feb 2019 05:25:42 -0500 Subject: [PATCH] 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: 9048b2e15b11c5 ("media: v4l: ioctl: Validate num_planes before using it") Signed-off-by: Ezequiel Garcia Reviewed-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/v4l2-core/v4l2-ioctl.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index 90aad465f9ed..206b7348797e 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -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); -- 2.45.2