1 files changed, 70 insertions, 0 deletions
diff --git a/t/t5619-clone-local-ambiguous-transport.sh b/t/t5619-clone-local-ambiguous-transport.sh
new file mode 100755
index 0000000..cce62bf
--- /dev/null
+++ b/t/t5619-clone-local-ambiguous-transport.sh
@@ -0,0 +1,70 @@
+#!/bin/sh
+
+test_description='test local clone with ambiguous transport'
+
+. ./test-lib.sh
+. "$TEST_DIRECTORY/lib-httpd.sh"
+
+if ! test_have_prereq SYMLINKS
+then
+	skip_all='skipping test, symlink support unavailable'
+	test_done
+fi
+
+start_httpd
+
+REPO="$HTTPD_DOCUMENT_ROOT_PATH/sub.git"
+URI="$HTTPD_URL/dumb/sub.git"
+
+test_expect_success 'setup' '
+	mkdir -p sensitive &&
+	echo "secret" >sensitive/secret &&
+
+	git init --bare "$REPO" &&
+	test_commit_bulk -C "$REPO" --ref=main 1 &&
+
+	git -C "$REPO" update-ref HEAD main &&
+	git -C "$REPO" update-server-info &&
+
+	git init malicious &&
+	(
+		cd malicious &&
+
+		git submodule add "$URI" &&
+
+		mkdir -p repo/refs &&
+		touch repo/refs/.gitkeep &&
+		printf "ref: refs/heads/a" >repo/HEAD &&
+		ln -s "$(cd .. && pwd)/sensitive" repo/objects &&
+
+		mkdir -p "$HTTPD_URL/dumb" &&
+		ln -s "../../../.git/modules/sub/../../../repo/" "$URI" &&
+
+		git add . &&
+		git commit -m "initial commit"
+	) &&
+
+	# Delete all of the references in our malicious submodule to
+	# avoid the client attempting to checkout any objects (which
+	# will be missing, and thus will cause the clone to fail before
+	# we can trigger the exploit).
+	git -C "$REPO" for-each-ref --format="delete %(refname)" >in &&
+	git -C "$REPO" update-ref --stdin <in &&
+	git -C "$REPO" update-server-info
+'
+
+test_expect_success 'ambiguous transport does not lead to arbitrary file-inclusion' '
+	git clone malicious clone &&
+	test_must_fail git -C clone submodule update --init 2>err &&
+
+	test_path_is_missing clone/.git/modules/sub/objects/secret &&
+	# We would actually expect "transport .file. not allowed" here,
+	# but due to quirks of the URL detection in Git, we mis-parse
+	# the absolute path as a bogus URL and die before that step.
+	#
+	# This works for now, and if we ever fix the URL detection, it
+	# is OK to change this to detect the transport error.
+	grep "protocol .* is not supported" err
+'
+
+test_done