Preallocate storage when parsing iref box and add debugging output

Resolves https://oss-fuzz.com/testcase-detail/5641604844748800

Author: baumanj

mp4parse/Cargo.toml

@@ -27,6 +27,7 @@ travis-ci = { repository = "https://github.com/mozilla/mp4parse-rust" }
 [dependencies]
 byteorder = "1.2.1"
 bitreader = { version = "0.3.2" }
+env_logger = "0.7.1"
 fallible_collections = { version = "0.3", features = ["std_io"] }
 hashbrown = "0.9"
 num-traits = "=0.2.10"
@@ -35,7 +36,6 @@ static_assertions = "1.1.0"
 
 [dev-dependencies]
 test-assembler = "0.1.2"
-env_logger = "0.7.1"
 walkdir = "2.3.1"
 criterion = "0.3"
 

mp4parse/src/lib.rs

@@ -1222,6 +1222,8 @@ fn skip_box_remain<T: Read>(src: &mut BMFFBox<T>) -> Result<()> {
 /// Metadata is accumulated in the passed-through `AvifContext` struct,
 /// which can be examined later.
 pub fn read_avif<T: Read>(f: &mut T, context: &mut AvifContext) -> Result<()> {
+    let _ = env_logger::try_init();
+
     let mut f = OffsetReader::new(f);
 
     let mut iter = BoxIter::new(&mut f);
@@ -1242,6 +1244,7 @@ pub fn read_avif<T: Read>(f: &mut T, context: &mut AvifContext) -> Result<()> {
     let mut mdats = TryVec::new();
 
     while let Some(mut b) = iter.next_box()? {
+        trace!("read_avif parsing {:?} box", b.head.name);
         match b.head.name {
             BoxType::MetadataBox => {
                 if meta.is_some() {
@@ -1359,6 +1362,7 @@ fn read_avif_meta<T: Read + Offset>(src: &mut BMFFBox<T>) -> Result<AvifMeta> {
 
     let mut iter = src.box_iter();
     while let Some(mut b) = iter.next_box()? {
+        trace!("read_avif_meta parsing {:?} box", b.head.name);
         match b.head.name {
             BoxType::ItemInfoBox => {
                 if item_infos.is_some() {
@@ -1529,12 +1533,14 @@ fn read_iref<T: Read>(src: &mut BMFFBox<T>) -> Result<TryVec<SingleItemTypeRefer
 
     let mut iter = src.box_iter();
     while let Some(mut b) = iter.next_box()? {
+        trace!("read_iref parsing {:?} referenceType", b.head.name);
         let from_item_id = if version == 0 {
             be_u16(&mut b)?.into()
         } else {
             be_u32(&mut b)?
         };
         let reference_count = be_u16(&mut b)?;
+        item_references.reserve(reference_count.to_usize())?;
         for _ in 0..reference_count {
             let to_item_id = if version == 0 {
                 be_u16(&mut b)?.into()

mp4parse/tests/public.rs

@@ -663,8 +663,6 @@ fn public_avif_primary_item_is_grid() {
 
 #[test]
 fn public_avif_read_samples() {
-    env_logger::init();
-
     for entry in walkdir::WalkDir::new(AVIF_TEST_DIR) {
         let entry = entry.expect("AVIF entry");
         let path = entry.path();