vorbis: fix panic on invalid encoding

Fixes #33
2018-02-07 18:35:49 +11:00 · 2018-02-07 18:35:49 +11:00 · d449289c5e
commit d449289c5e
parent 1582ebc2a4
1 changed files with 4 additions and 0 deletions
--- a/vorbis.go
+++ b/vorbis.go
@ -29,6 +29,10 @@ func (m *metadataVorbis) readVorbisComment(r io.Reader) error {
 		return err
 	}

+	if vendorLen < 0 {
+		return fmt.Errorf("invalid encoding: expected positive length, got %d", vendorLen)
+	}
+
 	vendor, err := readString(r, vendorLen)
 	if err != nil {
 		return err