avcodec/ffv1dec: More completely check micro_version

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

diff --git a/libavcodec/ffv1dec.c b/libavcodec/ffv1dec.c
index 621aac7..2463876 100644 (file)
--- a/libavcodec/ffv1dec.c
+++ b/libavcodec/ffv1dec.c
@@ -528,6 +528,8 @@ static int read_extra_header(FFV1Context *f)
     if (f->version > 2) {
         c->bytestream_end -= 4;
         f->micro_version = get_symbol(c, state, 0);
+        if (f->micro_version < 0)
+            return AVERROR_INVALIDDATA;
     }
     f->ac = f->avctx->coder_type = get_symbol(c, state, 0);
     if (f->ac > 1) {