From 3b59ead38ca719bfd52f016be9eb27897c3d33ae Mon Sep 17 00:00:00 2001
From: David Wiesen <iceweasel@openai.com>
Date: Tue, 5 May 2026 09:57:53 -0700
Subject: [PATCH] fix(windows): avoid WindowsApps shell aliases in sandbox

---
 codex-rs/core/src/shell.rs       | 42 ++++++++++++++++++++++++--------
 codex-rs/core/src/shell_tests.rs | 34 ++++++++++++++++++++++++++
 2 files changed, 66 insertions(+), 10 deletions(-)

diff --git a/codex-rs/core/src/shell.rs b/codex-rs/core/src/shell.rs
index 48c760d667..7093b769d5 100644
--- a/codex-rs/core/src/shell.rs
+++ b/codex-rs/core/src/shell.rs
@@ -162,6 +162,32 @@ fn file_exists(path: &PathBuf) -> Option<PathBuf> {
     }
 }
 
+fn is_windowsapps_app_execution_alias(path: &std::path::Path) -> bool {
+    path.to_string_lossy()
+        .to_ascii_lowercase()
+        .contains(r#"\appdata\local\microsoft\windowsapps\"#)
+}
+
+fn first_existing_fallback_path(fallback_paths: &[&str]) -> Option<PathBuf> {
+    for path in fallback_paths {
+        if let Some(path) = file_exists(&PathBuf::from(path)) {
+            return Some(path);
+        }
+    }
+
+    None
+}
+
+fn prefer_real_windows_shell_path(path: PathBuf, fallback_paths: &[&str]) -> PathBuf {
+    if is_windowsapps_app_execution_alias(&path)
+        && let Some(fallback) = first_existing_fallback_path(fallback_paths)
+    {
+        return fallback;
+    }
+
+    path
+}
+
 fn get_shell_path(
     shell_type: ShellType,
     provided_path: Option<&PathBuf>,
@@ -180,21 +206,17 @@ fn get_shell_path(
         && detect_shell_type(&default_shell_path) == Some(shell_type)
         && file_exists(&default_shell_path).is_some()
     {
-        return Some(default_shell_path);
+        return Some(prefer_real_windows_shell_path(
+            default_shell_path,
+            fallback_paths,
+        ));
     }
 
     if let Ok(path) = which::which(binary_name) {
-        return Some(path);
+        return Some(prefer_real_windows_shell_path(path, fallback_paths));
     }
 
-    for path in fallback_paths {
-        //check exists
-        if let Some(path) = file_exists(&PathBuf::from(path)) {
-            return Some(path);
-        }
-    }
-
-    None
+    first_existing_fallback_path(fallback_paths)
 }
 
 const ZSH_FALLBACK_PATHS: &[&str] = &["/bin/zsh"];
diff --git a/codex-rs/core/src/shell_tests.rs b/codex-rs/core/src/shell_tests.rs
index f0974900b2..2438f16bd7 100644
--- a/codex-rs/core/src/shell_tests.rs
+++ b/codex-rs/core/src/shell_tests.rs
@@ -1,6 +1,7 @@
 use super::*;
 use std::path::PathBuf;
 use std::process::Command;
+use tempfile::tempdir;
 
 #[test]
 #[cfg(target_os = "macos")]
@@ -190,3 +191,36 @@ fn finds_powershell() {
 
     assert!(shell_path.ends_with("pwsh.exe") || shell_path.ends_with("powershell.exe"));
 }
+
+#[test]
+fn detects_windowsapps_app_execution_alias() {
+    assert!(is_windowsapps_app_execution_alias(&PathBuf::from(
+        r#"C:\Users\alice\AppData\Local\Microsoft\WindowsApps\pwsh.exe"#
+    )));
+    assert!(!is_windowsapps_app_execution_alias(&PathBuf::from(
+        r#"C:\Program Files\PowerShell\7\pwsh.exe"#
+    )));
+}
+
+#[test]
+fn prefers_real_shell_binary_over_windowsapps_alias() {
+    let temp = tempdir().unwrap();
+    let fallback = temp.path().join("pwsh.exe");
+    std::fs::write(&fallback, b"").unwrap();
+
+    let selected = prefer_real_windows_shell_path(
+        PathBuf::from(r#"C:\Users\alice\AppData\Local\Microsoft\WindowsApps\pwsh.exe"#),
+        &[fallback.to_str().unwrap()],
+    );
+
+    assert_eq!(selected, fallback);
+}
+
+#[test]
+fn keeps_windowsapps_alias_when_no_real_shell_exists() {
+    let alias = PathBuf::from(r#"C:\Users\alice\AppData\Local\Microsoft\WindowsApps\pwsh.exe"#);
+
+    let selected = prefer_real_windows_shell_path(alias.clone(), &[]);
+
+    assert_eq!(selected, alias);
+}