fix: Handle sync_manifest failures.

CHANGELOG.md

@@ -9,6 +9,7 @@
 #### 🐞 Fixes
 
 - Will now respect the `RUSTUP_HOME` environment variable when locating the `.rustup` store.
+- Fixed an issue where `sync_manifest` would fail if we didn't have read access to the rustup store.
 
 #### ⚙️ Internal
 

src/proto.rs

@@ -249,7 +249,12 @@ pub fn sync_manifest(Json(_): Json<SyncManifestInput>) -> FnResult<Json<SyncMani
     let mut output = SyncManifestOutput::default();
     let mut versions = vec![];
 
-    for dir in fs::read_dir(get_rustup_home(&env)?.join("toolchains"))? {
+    // Path may not be whitelisted, so exit early instead of failing
+    let Ok(dirs) = fs::read_dir(get_rustup_home(&env)?.join("toolchains")) else {
+        return Ok(Json(output));
+    };
+
+    for dir in dirs {
         let dir = dir?.path();
 
         if !dir.is_dir() {