Add av_image_check_sar() and use it to validate SAR

1 files changed, 8 insertions, 0 deletions

diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index 8f7b2bf32e..703491ecd8 100644
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -328,6 +328,14 @@ static int decode_slice_header(FFV1Context *f, FFV1Context *fs)
     f->cur->sample_aspect_ratio.num = get_symbol(c, state, 0);
     f->cur->sample_aspect_ratio.den = get_symbol(c, state, 0);
 
+    if (av_image_check_sar(f->width, f->height,
+                           f->cur->sample_aspect_ratio) < 0) {
+        av_log(f->avctx, AV_LOG_WARNING, "ignoring invalid SAR: %u/%u\n",
+               f->cur->sample_aspect_ratio.num,
+               f->cur->sample_aspect_ratio.den);
+        f->cur->sample_aspect_ratio = (AVRational){ 0, 1 };
+    }
+
     return 0;
 }