video-converter: Add checks for configuration sanity.

If the cropping or scaling input or output rects put us completely
outside the input/output frame respectively, we can't draw anything
except black safely. Check for those conditions and don't set up a
configuration that attempts to access out of bounds memory outside
the input/output framebuffers.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/696>
This commit is contained in:
Jan Schmidt 2020-06-06 01:22:21 +10:00 committed by GStreamer Merge Bot
parent bf5d51c5da
commit 205bb066ed
2 changed files with 80 additions and 30 deletions

View file

@ -2335,8 +2335,17 @@ gst_video_converter_new (GstVideoInfo * in_info, GstVideoInfo * out_info,
convert->in_width =
MIN (convert->in_width, convert->in_maxwidth - convert->in_x);
if (convert->in_width + convert->in_x < 0 ||
convert->in_width + convert->in_x > convert->in_maxwidth) {
convert->in_width = 0;
}
convert->in_height =
MIN (convert->in_height, convert->in_maxheight - convert->in_y);
if (convert->in_height + convert->in_y < 0 ||
convert->in_height + convert->in_y > convert->in_maxheight) {
convert->in_height = 0;
}
convert->out_x = get_opt_int (convert, GST_VIDEO_CONVERTER_OPT_DEST_X, 0);
convert->out_y = get_opt_int (convert, GST_VIDEO_CONVERTER_OPT_DEST_Y, 0);
@ -2350,10 +2359,25 @@ gst_video_converter_new (GstVideoInfo * in_info, GstVideoInfo * out_info,
get_opt_int (convert, GST_VIDEO_CONVERTER_OPT_DEST_HEIGHT,
convert->out_maxheight - convert->out_y);
convert->out_width =
MIN (convert->out_width, convert->out_maxwidth - convert->out_x);
convert->out_height =
MIN (convert->out_height, convert->out_maxheight - convert->out_y);
if (convert->out_width > convert->out_maxwidth - convert->out_x)
convert->out_width = convert->out_maxwidth - convert->out_x;
convert->out_width = CLAMP (convert->out_width, 0, convert->out_maxwidth);
/* Check if completely outside the framebuffer */
if (convert->out_width + convert->out_x < 0 ||
convert->out_width + convert->out_x > convert->out_maxwidth) {
convert->out_width = 0;
}
/* Same for height */
if (convert->out_height > convert->out_maxheight - convert->out_y)
convert->out_height = convert->out_maxheight - convert->out_y;
convert->out_height = CLAMP (convert->out_height, 0, convert->out_maxheight);
if (convert->out_height + convert->out_y < 0 ||
convert->out_height + convert->out_y > convert->out_maxheight) {
convert->out_height = 0;
}
convert->fill_border = GET_OPT_FILL_BORDER (convert);
convert->border_argb = get_opt_uint (convert,
@ -2396,6 +2420,9 @@ gst_video_converter_new (GstVideoInfo * in_info, GstVideoInfo * out_info,
/* Magic number of 200 lines */
if (MAX (convert->out_height, convert->in_height) / n_threads < 200)
n_threads = (MAX (convert->out_height, convert->in_height) + 199) / 200;
if (n_threads < 1)
n_threads = 1;
convert->conversion_runner = gst_parallelized_task_runner_new (n_threads);
if (video_converter_lookup_fastpath (convert))
@ -2429,33 +2456,36 @@ gst_video_converter_new (GstVideoInfo * in_info, GstVideoInfo * out_info,
convert->dither_lines = g_new0 (GstLineCache *, n_threads);
convert->dither = g_new0 (GstVideoDither *, n_threads);
for (i = 0; i < n_threads; i++) {
convert->current_format = GST_VIDEO_INFO_FORMAT (in_info);
convert->current_width = convert->in_width;
convert->current_height = convert->in_height;
if (convert->in_width > 0 && convert->out_width > 0 && convert->in_height > 0
&& convert->out_height > 0) {
for (i = 0; i < n_threads; i++) {
convert->current_format = GST_VIDEO_INFO_FORMAT (in_info);
convert->current_width = convert->in_width;
convert->current_height = convert->in_height;
/* unpack */
prev = chain_unpack_line (convert, i);
/* upsample chroma */
prev = chain_upsample (convert, prev, i);
/* convert to gamma decoded RGB */
prev = chain_convert_to_RGB (convert, prev, i);
/* do all downscaling */
prev = chain_scale (convert, prev, FALSE, i);
/* do conversion between color spaces */
prev = chain_convert (convert, prev, i);
/* do alpha channels */
prev = chain_alpha (convert, prev, i);
/* do all remaining (up)scaling */
prev = chain_scale (convert, prev, TRUE, i);
/* convert to gamma encoded Y'Cb'Cr' */
prev = chain_convert_to_YUV (convert, prev, i);
/* downsample chroma */
prev = chain_downsample (convert, prev, i);
/* dither */
prev = chain_dither (convert, prev, i);
/* pack into final format */
convert->pack_lines[i] = chain_pack (convert, prev, i);
/* unpack */
prev = chain_unpack_line (convert, i);
/* upsample chroma */
prev = chain_upsample (convert, prev, i);
/* convert to gamma decoded RGB */
prev = chain_convert_to_RGB (convert, prev, i);
/* do all downscaling */
prev = chain_scale (convert, prev, FALSE, i);
/* do conversion between color spaces */
prev = chain_convert (convert, prev, i);
/* do alpha channels */
prev = chain_alpha (convert, prev, i);
/* do all remaining (up)scaling */
prev = chain_scale (convert, prev, TRUE, i);
/* convert to gamma encoded Y'Cb'Cr' */
prev = chain_convert_to_YUV (convert, prev, i);
/* downsample chroma */
prev = chain_downsample (convert, prev, i);
/* dither */
prev = chain_dither (convert, prev, i);
/* pack into final format */
convert->pack_lines[i] = chain_pack (convert, prev, i);
}
}
setup_borderline (convert);
@ -2695,6 +2725,10 @@ gst_video_converter_frame (GstVideoConverter * convert,
return;
}
if (G_UNLIKELY (convert->in_width == 0 || convert->in_height == 0 ||
convert->out_width == 0 || convert->out_height == 0))
return;
convert->convert (convert, src, dest);
}

View file

@ -2691,7 +2691,23 @@ GST_START_TEST (test_video_convert)
320));
gst_video_frame_map (&inframe, &ininfo, inbuffer, GST_MAP_READ);
ASSERT_CRITICAL (gst_video_converter_frame (convert, &inframe, &outframe));
gst_video_converter_free (convert);
/* Make sure we can crop the entire frame away without dying */
convert = gst_video_converter_new (&ininfo, &outinfo,
gst_structure_new ("options",
GST_VIDEO_CONVERTER_OPT_RESAMPLER_METHOD,
GST_TYPE_VIDEO_RESAMPLER_METHOD, 3,
GST_VIDEO_CONVERTER_OPT_SRC_X, G_TYPE_INT, -500,
GST_VIDEO_CONVERTER_OPT_SRC_Y, G_TYPE_INT, -500,
GST_VIDEO_CONVERTER_OPT_SRC_WIDTH, G_TYPE_INT, 300,
GST_VIDEO_CONVERTER_OPT_SRC_HEIGHT, G_TYPE_INT, 220,
GST_VIDEO_CONVERTER_OPT_DEST_X, G_TYPE_INT, 800,
GST_VIDEO_CONVERTER_OPT_DEST_Y, G_TYPE_INT, 600,
GST_VIDEO_CONVERTER_OPT_DEST_WIDTH, G_TYPE_INT, 310,
GST_VIDEO_CONVERTER_OPT_DEST_HEIGHT, G_TYPE_INT, 230, NULL));
gst_video_converter_frame (convert, &inframe, &outframe);
gst_video_converter_free (convert);
gst_video_frame_unmap (&outframe);