diff --git a/libavdevice/xcbgrab.c b/libavdevice/xcbgrab.c index 2878995412..15512cd15f 100644 --- a/libavdevice/xcbgrab.c +++ b/libavdevice/xcbgrab.c @@ -533,8 +533,17 @@ static int create_stream(AVFormatContext *s) gc = xcb_get_geometry(c->conn, c->screen->root); geo = xcb_get_geometry_reply(c->conn, gc, NULL); - c->width = FFMIN(geo->width, c->width); - c->height = FFMIN(geo->height, c->height); + if (c->x + c->width >= geo->width || + c->y + c->height >= geo->height) { + av_log(s, AV_LOG_ERROR, + "Capture area %dx%d at position %d.%d " + "outside the screen size %dx%d\n", + c->width, c->height, + c->x, c->y, + geo->width, geo->height); + return AVERROR(EINVAL); + } + c->time_base = (AVRational){ st->avg_frame_rate.den, st->avg_frame_rate.num }; c->time_frame = av_gettime();