diff --git a/libavformat/dsfdec.c b/libavformat/dsfdec.c
index 41538fd83c..6ef66ba930 100644
--- a/libavformat/dsfdec.c
+++ b/libavformat/dsfdec.c
@@ -122,8 +122,8 @@ static int dsf_read_header(AVFormatContext *s)
 
     avio_skip(pb, 8);
     st->codecpar->block_align = avio_rl32(pb);
-    if (st->codecpar->block_align > INT_MAX / st->codecpar->channels) {
-        avpriv_request_sample(s, "block_align overflow");
+    if (st->codecpar->block_align > INT_MAX / st->codecpar->channels || st->codecpar->block_align <= 0) {
+        avpriv_request_sample(s, "block_align invalid");
         return AVERROR_INVALIDDATA;
     }
     st->codecpar->block_align *= st->codecpar->channels;