diff --git a/libavformat/rmdec.c b/libavformat/rmdec.c
index 5dfbc4a0ef..9445356695 100644
--- a/libavformat/rmdec.c
+++ b/libavformat/rmdec.c
@@ -295,7 +295,7 @@ static int rm_read_audio_stream_info(AVFormatContext *s, AVIOContext *pb,
             ast->deint_id == DEINT_ID_GENR ||
             ast->deint_id == DEINT_ID_SIPR) {
             if (st->codecpar->block_align <= 0 ||
-                ast->audio_framesize * sub_packet_h > (unsigned)INT_MAX ||
+                ast->audio_framesize * (uint64_t)sub_packet_h > (unsigned)INT_MAX ||
                 ast->audio_framesize * sub_packet_h < st->codecpar->block_align)
                 return AVERROR_INVALIDDATA;
             if (av_new_packet(&ast->pkt, ast->audio_framesize * sub_packet_h) < 0)