diff --git a/ecs/main.py b/ecs/main.py index 171e5ed..2a522a7 100644 --- a/ecs/main.py +++ b/ecs/main.py @@ -32,7 +32,26 @@ def create_model(): boto3.client('s3').download_file(bucket, key, fname) if fname.endswith('.tar.gz'): with tarfile.open(fname, 'r:gz') as f: - f.extractall() + def is_within_directory(directory, target): + + abs_directory = os.path.abspath(directory) + abs_target = os.path.abspath(target) + + prefix = os.path.commonprefix([abs_directory, abs_target]) + + return prefix == abs_directory + + def safe_extract(tar, path=".", members=None, *, numeric_owner=False): + + for member in tar.getmembers(): + member_path = os.path.join(path, member.name) + if not is_within_directory(path, member_path): + raise Exception("Attempted Path Traversal in Tar File") + + tar.extractall(path, members, numeric_owner=numeric_owner) + + + safe_extract(f) return load_model('model.pt') diff --git a/src/am/sage_maker.py b/src/am/sage_maker.py index e5fa330..82aff67 100644 --- a/src/am/sage_maker.py +++ b/src/am/sage_maker.py @@ -12,7 +12,29 @@ def download_training_artifacts(sagemaker_session, prefix, local_dir): for archive_path in Path(local_dir).iterdir(): if archive_path.name.endswith('tar.gz'): with tarfile.open(archive_path, 'r:gz') as f: - f.extractall(local_dir) + + import os + + def is_within_directory(directory, target): + + abs_directory = os.path.abspath(directory) + abs_target = os.path.abspath(target) + + prefix = os.path.commonprefix([abs_directory, abs_target]) + + return prefix == abs_directory + + def safe_extract(tar, path=".", members=None, *, numeric_owner=False): + + for member in tar.getmembers(): + member_path = os.path.join(path, member.name) + if not is_within_directory(path, member_path): + raise Exception("Attempted Path Traversal in Tar File") + + tar.extractall(path, members, numeric_owner=numeric_owner) + + + safe_extract(f, local_dir) archive_path.unlink()