From aff1dc9c3efd46a5b1c23c73ac35b7c43139f143 Mon Sep 17 00:00:00 2001
From: Santiago Martinez <santiago.mbal@gmail.com>
Date: Mon, 21 Aug 2023 22:11:00 +0100
Subject: [PATCH] Fix: Avoid infinite loops when parsing chunks

---
 src/soundevent/audio/chunks.py | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/src/soundevent/audio/chunks.py b/src/soundevent/audio/chunks.py
index 10af968..0047508 100644
--- a/src/soundevent/audio/chunks.py
+++ b/src/soundevent/audio/chunks.py
@@ -70,11 +70,15 @@ def _get_subchunks(riff: BinaryIO, size: int) -> List[Chunk]:
     subchunks = []
     while riff.tell() < start_position + size - 1:
         subchunk = _read_chunk(riff)
+
+        if subchunk is None:
+            break
+
         subchunks.append(subchunk)
     return subchunks
 
 
-def _read_chunk(riff: BinaryIO) -> Chunk:
+def _read_chunk(riff: BinaryIO) -> Chunk | None:
     """Read a chunk from a RIFF file at current pointer position.
 
     We assume the file pointer is at the beginning of the chunk.
@@ -91,6 +95,10 @@ def _read_chunk(riff: BinaryIO) -> Chunk:
     chunk_id = riff.read(4).decode("ascii")
     size = int.from_bytes(riff.read(4), "little")
 
+    if size == 0:
+        # Make sure we don't get stuck in an infinite loop.
+        return None
+
     identifier = None
     if chunk_id in CHUNKS_WITH_SUBCHUNKS:
         identifier = riff.read(4).decode("ascii")
@@ -124,6 +132,16 @@ def parse_into_chunks(riff: BinaryIO) -> Chunk:
     Returns
     -------
     Chunk
+
+    Raises
+    ------
+    ValueError
+        If the RIFF file is empty.
     """
     riff.seek(0)
-    return _read_chunk(riff)
+    chunk = _read_chunk(riff)
+
+    if chunk is None:
+        raise ValueError("RIFF file is empty")
+
+    return chunk