add test, update changelog

CHANGELOG.md

@@ -6,6 +6,7 @@ Blocks of changes will separated by version increments.
 
 ## **[Unreleased]**
 
+- [#463](https://github.com/wasmerio/wasmer/pull/463) Fix bug in WASI path_open allowing one level above preopened dir to be accessed
 - [#461](https://github.com/wasmerio/wasmer/pull/461) Prevent passing negative lengths in various places in the runtime C API
 - [#459](https://github.com/wasmerio/wasmer/pull/459) Add monotonic and real time clocks for wasi on windows
 - [#447](https://github.com/wasmerio/wasmer/pull/447) Add trace macro (`--features trace`) for more verbose debug statements

lib/wasi/tests/wasitests/fs_sandbox_test.rs

@@ -0,0 +1,9 @@
+#[test]
+fn test_fs_sandbox_test() {
+    assert_wasi_output!(
+        "../../wasitests/fs_sandbox_test.wasm",
+        "fs_sandbox_test",
+        vec![],
+        "../../wasitests/fs_sandbox_test.out"
+    );
+}

lib/wasi/tests/wasitests/mod.rs

@@ -7,6 +7,7 @@
 mod _common;
 mod create_dir;
 mod file_metadata;
+mod fs_sandbox_test;
 mod hello;
 mod mapdir;
 mod quine;

lib/wasi/wasitests/fs_sandbox_test.out

@@ -0,0 +1 @@
+Reading the parent directory was okay? false

lib/wasi/wasitests/fs_sandbox_test.rs

@@ -0,0 +1,10 @@
+fn main() {
+    #[cfg(target = "wasi")]
+    let result = std::fs::read_dir("..");
+    #[cfg(not(target = "wasi"))]
+    let result: Result<(), String> = Err("placeholder".to_string());
+    println!(
+        "Reading the parent directory was okay? {:?}",
+        result.is_ok()
+    );
+}