diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index 7dcce95caa..b24be3192b 100644
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -408,6 +408,7 @@ static int decode_slice(AVCodecContext *c, void *arg)
         if (ffv1_init_slice_state(f, fs) < 0)
             return AVERROR(ENOMEM);
         if (decode_slice_header(f, fs) < 0) {
+            fs->slice_x = fs->slice_y = fs->slice_height = fs->slice_width = 0;
             fs->slice_damaged = 1;
             return AVERROR_INVALIDDATA;
         }