diff --git a/libavformat/tta.c b/libavformat/tta.c
index 70e98b2937..46c2508bce 100644
--- a/libavformat/tta.c
+++ b/libavformat/tta.c
@@ -119,7 +119,7 @@ static int tta_read_header(AVFormatContext *s)
     for (i = 0; i < c->totalframes; i++) {
         uint32_t size = avio_rl32(s->pb);
         int r;
-        if ((r = av_add_index_entry(st, framepos, i * c->frame_size, size, 0,
+        if ((r = av_add_index_entry(st, framepos, i * (int64_t)c->frame_size, size, 0,
                                     AVINDEX_KEYFRAME)) < 0)
             return r;
         framepos += size;