From 5b50b456410eb7eaf50e12abe21730cc65a49078 Mon Sep 17 00:00:00 2001 From: Trent Piepho Date: Thu, 30 Apr 2009 17:03:34 -0700 Subject: v4l2-ioctl: Clear buffer type specific trailing fields/padding MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Trent Piepho Some ioctls have structs that are a different size depending on what type of buffer is being used. If the buffer type leaves a field unused or has padding space at the end, this space should be zeroed out. The problems with S_FMT and REQBUFS were original identified and patched by Márton Németh . Priority: normal Signed-off-by: Trent Piepho --- linux/drivers/media/video/v4l2-ioctl.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'linux/drivers/media/video') diff --git a/linux/drivers/media/video/v4l2-ioctl.c b/linux/drivers/media/video/v4l2-ioctl.c index e3eea7c71..22b380dfd 100644 --- a/linux/drivers/media/video/v4l2-ioctl.c +++ b/linux/drivers/media/video/v4l2-ioctl.c @@ -43,6 +43,12 @@ printk(KERN_DEBUG "%s: " fmt, vfd->name, ## arg);\ } while (0) +/* Zero out the end of the struct pointed to by p. Everthing after, but + * not including, the specified field is cleared. */ +#define CLEAR_AFTER_FIELD(p, field) \ + memset((u8 *)(p) + offsetof(typeof(*(p)), field) + sizeof((p)->field), \ + 0, sizeof(*(p)) - offsetof(typeof(*(p)), field) - sizeof((p)->field)) + struct std_descr { v4l2_std_id std; const char *descr; @@ -783,44 +789,53 @@ static long __video_do_ioctl(struct file *file, switch (f->type) { case V4L2_BUF_TYPE_VIDEO_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.pix); v4l_print_pix_fmt(vfd, &f->fmt.pix); if (ops->vidioc_s_fmt_vid_cap) ret = ops->vidioc_s_fmt_vid_cap(file, fh, f); break; case V4L2_BUF_TYPE_VIDEO_OVERLAY: + CLEAR_AFTER_FIELD(f, fmt.win); if (ops->vidioc_s_fmt_vid_overlay) ret = ops->vidioc_s_fmt_vid_overlay(file, fh, f); break; case V4L2_BUF_TYPE_VIDEO_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.pix); v4l_print_pix_fmt(vfd, &f->fmt.pix); if (ops->vidioc_s_fmt_vid_out) ret = ops->vidioc_s_fmt_vid_out(file, fh, f); break; case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY: + CLEAR_AFTER_FIELD(f, fmt.win); if (ops->vidioc_s_fmt_vid_out_overlay) ret = ops->vidioc_s_fmt_vid_out_overlay(file, fh, f); break; case V4L2_BUF_TYPE_VBI_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.vbi); if (ops->vidioc_s_fmt_vbi_cap) ret = ops->vidioc_s_fmt_vbi_cap(file, fh, f); break; case V4L2_BUF_TYPE_VBI_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.vbi); if (ops->vidioc_s_fmt_vbi_out) ret = ops->vidioc_s_fmt_vbi_out(file, fh, f); break; case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.sliced); if (ops->vidioc_s_fmt_sliced_vbi_cap) ret = ops->vidioc_s_fmt_sliced_vbi_cap(file, fh, f); break; case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.sliced); if (ops->vidioc_s_fmt_sliced_vbi_out) ret = ops->vidioc_s_fmt_sliced_vbi_out(file, fh, f); break; case V4L2_BUF_TYPE_PRIVATE: + /* CLEAR_AFTER_FIELD(f, fmt.raw_data); <- does nothing */ if (ops->vidioc_s_fmt_type_private) ret = ops->vidioc_s_fmt_type_private(file, fh, f); @@ -837,46 +852,55 @@ static long __video_do_ioctl(struct file *file, v4l2_type_names)); switch (f->type) { case V4L2_BUF_TYPE_VIDEO_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.pix); if (ops->vidioc_try_fmt_vid_cap) ret = ops->vidioc_try_fmt_vid_cap(file, fh, f); if (!ret) v4l_print_pix_fmt(vfd, &f->fmt.pix); break; case V4L2_BUF_TYPE_VIDEO_OVERLAY: + CLEAR_AFTER_FIELD(f, fmt.win); if (ops->vidioc_try_fmt_vid_overlay) ret = ops->vidioc_try_fmt_vid_overlay(file, fh, f); break; case V4L2_BUF_TYPE_VIDEO_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.pix); if (ops->vidioc_try_fmt_vid_out) ret = ops->vidioc_try_fmt_vid_out(file, fh, f); if (!ret) v4l_print_pix_fmt(vfd, &f->fmt.pix); break; case V4L2_BUF_TYPE_VIDEO_OUTPUT_OVERLAY: + CLEAR_AFTER_FIELD(f, fmt.win); if (ops->vidioc_try_fmt_vid_out_overlay) ret = ops->vidioc_try_fmt_vid_out_overlay(file, fh, f); break; case V4L2_BUF_TYPE_VBI_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.vbi); if (ops->vidioc_try_fmt_vbi_cap) ret = ops->vidioc_try_fmt_vbi_cap(file, fh, f); break; case V4L2_BUF_TYPE_VBI_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.vbi); if (ops->vidioc_try_fmt_vbi_out) ret = ops->vidioc_try_fmt_vbi_out(file, fh, f); break; case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE: + CLEAR_AFTER_FIELD(f, fmt.sliced); if (ops->vidioc_try_fmt_sliced_vbi_cap) ret = ops->vidioc_try_fmt_sliced_vbi_cap(file, fh, f); break; case V4L2_BUF_TYPE_SLICED_VBI_OUTPUT: + CLEAR_AFTER_FIELD(f, fmt.sliced); if (ops->vidioc_try_fmt_sliced_vbi_out) ret = ops->vidioc_try_fmt_sliced_vbi_out(file, fh, f); break; case V4L2_BUF_TYPE_PRIVATE: + /* CLEAR_AFTER_FIELD(f, fmt.raw_data); <- does nothing */ if (ops->vidioc_try_fmt_type_private) ret = ops->vidioc_try_fmt_type_private(file, fh, f); @@ -899,6 +923,9 @@ static long __video_do_ioctl(struct file *file, if (ret) break; + if (p->type < V4L2_BUF_TYPE_PRIVATE) + CLEAR_AFTER_FIELD(p, memory); + ret = ops->vidioc_reqbufs(file, fh, p); dbgarg(cmd, "count=%d, type=%s, memory=%s\n", p->count, -- cgit v1.2.3