diff --git a/libavcodec/qdm2.c b/libavcodec/qdm2.c
index ac8ae8cbbb..7b9d50b234 100644
--- a/libavcodec/qdm2.c
+++ b/libavcodec/qdm2.c
@@ -1704,7 +1704,7 @@ static av_cold int qdm2_decode_init(AVCodecContext *avctx)
     s->group_size = bytestream2_get_be32(&gb);
     s->fft_size = bytestream2_get_be32(&gb);
     s->checksum_size = bytestream2_get_be32(&gb);
-    if (s->checksum_size >= 1U << 28 || !s->checksum_size) {
+    if (s->checksum_size >= 1U << 28 || s->checksum_size <= 1) {
         av_log(avctx, AV_LOG_ERROR, "data block size invalid (%u)\n", s->checksum_size);
         return AVERROR_INVALIDDATA;
     }