Fuzz: Add EbmlFile fuzz target

Author: Serial-ATA

fuzz/Cargo.toml

@@ -42,6 +42,10 @@ path = "fuzz_targets/aifffile_read_from.rs"
 name = "apefile_read_from"
 path = "fuzz_targets/apefile_read_from.rs"
 
+[[bin]]
+name = "ebmlfile_read_from"
+path = "fuzz_targets/ebmlfile_read_from.rs"
+
 [[bin]]
 name = "flacfile_read_from"
 path = "fuzz_targets/flacfile_read_from.rs"

fuzz/fuzz_targets/ebmlfile_read_from.rs

@@ -0,0 +1,11 @@
+#![no_main]
+
+use std::io::Cursor;
+
+use libfuzzer_sys::fuzz_target;
+use lofty::config::ParseOptions;
+use lofty::file::AudioFile;
+
+fuzz_target!(|data: Vec<u8>| {
+	let _ = lofty::ebml::EbmlFile::read_from(&mut Cursor::new(data), ParseOptions::new());
+});

lofty/src/ebml/read/segment.rs

@@ -38,14 +38,11 @@ where
 				ElementIdent::Tracks if parse_options.read_properties => {
 					segment_tracks::read_from(element_reader, parse_options, properties)?
 				},
-				ElementIdent::Tags | ElementIdent::Chapters if parse_options.read_tags => {
+				// TODO: ElementIdent::Chapters
+				ElementIdent::Tags if parse_options.read_tags => {
 					let mut tag = tags.unwrap_or_default();
 
-					if id == ElementIdent::Tags {
-						segment_tags::read_from(element_reader, parse_options, &mut tag)?
-					} else {
-						segment_chapters::read_from(element_reader, parse_options, &mut tag)?
-					}
+					segment_tags::read_from(element_reader, parse_options, &mut tag)?;
 
 					tags = Some(tag);
 				},

lofty/src/ebml/read/segment_chapters.rs

@@ -5,6 +5,7 @@ use crate::error::Result;
 
 use std::io::{Read, Seek};
 
+#[allow(dead_code)]
 pub(super) fn read_from<R>(
 	_element_reader: &mut ElementReader<R>,
 	_parse_options: ParseOptions,

lofty/tests/fuzz/assets/ebmlfile_read_from/.gitkeep

@@ -7,6 +7,7 @@ use std::thread;
 use std::time::Instant;
 
 mod aifffile_read_from;
+mod ebmlfile_read_from;
 mod flacfile_read_from;
 mod id3v2;
 mod mp4file_read_from;