diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c
index 953421435d..a72bcb0ba1 100644
--- a/libavformat/matroskaenc.c
+++ b/libavformat/matroskaenc.c
@@ -2079,14 +2079,14 @@ fail:
     return ret;
 }
 
-static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
-                            uint32_t blockid, AVPacket *pkt, int keyframe)
+static int mkv_write_block(AVFormatContext *s, AVIOContext *pb,
+                           uint32_t blockid, AVPacket *pkt, int keyframe)
 {
     MatroskaMuxContext *mkv = s->priv_data;
     AVCodecParameters *par = s->streams[pkt->stream_index]->codecpar;
     mkv_track *track = &mkv->tracks[pkt->stream_index];
     uint8_t *data = NULL, *side_data = NULL;
-    int offset = 0, size = pkt->size, side_data_size = 0;
+    int err = 0, offset = 0, size = pkt->size, side_data_size = 0;
     int64_t ts = track->write_dts ? pkt->dts : pkt->pts;
     uint64_t additional_id = 0;
     int64_t discard_padding = 0;
@@ -2105,22 +2105,24 @@ static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
            mkv->cluster_pos, track_number, keyframe != 0);
     if (par->codec_id == AV_CODEC_ID_H264 && par->extradata_size > 0 &&
         (AV_RB24(par->extradata) == 1 || AV_RB32(par->extradata) == 1))
-        ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
+        err = ff_avc_parse_nal_units_buf(pkt->data, &data, &size);
     else if (par->codec_id == AV_CODEC_ID_HEVC && par->extradata_size > 6 &&
              (AV_RB24(par->extradata) == 1 || AV_RB32(par->extradata) == 1))
         /* extradata is Annex B, assume the bitstream is too and convert it */
-        ff_hevc_annexb2mp4_buf(pkt->data, &data, &size, 0, NULL);
+        err = ff_hevc_annexb2mp4_buf(pkt->data, &data, &size, 0, NULL);
     else if (par->codec_id == AV_CODEC_ID_AV1)
-        ff_av1_filter_obus_buf(pkt->data, &data, &size);
+        err = ff_av1_filter_obus_buf(pkt->data, &data, &size);
     else if (par->codec_id == AV_CODEC_ID_WAVPACK) {
-        int ret = mkv_strip_wavpack(pkt->data, &data, &size);
-        if (ret < 0) {
-            av_log(s, AV_LOG_ERROR, "Error stripping a WavPack packet.\n");
-            return;
-        }
+        err = mkv_strip_wavpack(pkt->data, &data, &size);
     } else
         data = pkt->data;
 
+    if (err < 0) {
+        av_log(s, AV_LOG_ERROR, "Error when reformatting data of "
+               "a packet from stream %d.\n", pkt->stream_index);
+        return err;
+    }
+
     if (par->codec_id == AV_CODEC_ID_PRORES && size >= 8) {
         /* Matroska specification requires to remove the first QuickTime atom
          */
@@ -2184,6 +2186,8 @@ static void mkv_write_block(AVFormatContext *s, AVIOContext *pb,
     if ((side_data_size && additional_id == 1) || discard_padding) {
         end_ebml_master(pb, block_group);
     }
+
+    return 0;
 }
 
 static int mkv_write_vtt_blocks(AVFormatContext *s, AVIOContext *pb, AVPacket *pkt)
@@ -2389,7 +2393,9 @@ static int mkv_write_packet_internal(AVFormatContext *s, AVPacket *pkt, int add_
     relative_packet_pos = avio_tell(pb);
 
     if (par->codec_type != AVMEDIA_TYPE_SUBTITLE) {
-        mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe);
+        ret = mkv_write_block(s, pb, MATROSKA_ID_SIMPLEBLOCK, pkt, keyframe);
+        if (ret < 0)
+            return ret;
         if ((s->pb->seekable & AVIO_SEEKABLE_NORMAL) && (par->codec_type == AVMEDIA_TYPE_VIDEO && keyframe || add_cue)) {
             ret = mkv_add_cuepoint(mkv->cues, pkt->stream_index, tracknum, ts, mkv->cluster_pos, relative_packet_pos, -1);
             if (ret < 0) return ret;