diff --git a/libavformat/mov.c b/libavformat/mov.c
index 396a559fa4..64e943f73e 100644
--- a/libavformat/mov.c
+++ b/libavformat/mov.c
@@ -3209,6 +3209,12 @@ static int mov_read_stsd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
     st = c->fc->streams[c->fc->nb_streams - 1];
     sc = st->priv_data;
 
+    if (sc->extradata) {
+        av_log(c->fc, AV_LOG_ERROR,
+               "Duplicate stsd found in this track.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
     sc->stsd_version = avio_r8(pb);
     avio_rb24(pb); /* flags */
     entries = avio_rb32(pb);
@@ -3219,12 +3225,6 @@ static int mov_read_stsd(MOVContext *c, AVIOContext *pb, MOVAtom atom)
         return AVERROR_INVALIDDATA;
     }
 
-    if (sc->extradata) {
-        av_log(c->fc, AV_LOG_ERROR,
-               "Duplicate stsd found in this track.\n");
-        return AVERROR_INVALIDDATA;
-    }
-
     /* Prepare space for hosting multiple extradata. */
     sc->extradata = av_calloc(entries, sizeof(*sc->extradata));
     if (!sc->extradata)