From 53b29d8a47326a4613d772fd8d175c626f5d345c Mon Sep 17 00:00:00 2001
From: "google-labs-jules[bot]"
 <161369871+google-labs-jules[bot]@users.noreply.github.com>
Date: Thu, 18 Jun 2026 06:20:57 +0000
Subject: [PATCH] =?UTF-8?q?=F0=9F=9B=A1=EF=B8=8F=20Sentinel:=20[CRITICAL]?=
 =?UTF-8?q?=20Fix=20TOCTOU=20symlink=20attack=20in=20permission=20hardenin?=
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Co-authored-by: acebytes <2820910+acebytes@users.noreply.github.com>
---
 Sources/Cacheout/Headless/DaemonMode.swift | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/Sources/Cacheout/Headless/DaemonMode.swift b/Sources/Cacheout/Headless/DaemonMode.swift
index 23b86f7..92a8d6f 100644
--- a/Sources/Cacheout/Headless/DaemonMode.swift
+++ b/Sources/Cacheout/Headless/DaemonMode.swift
@@ -295,10 +295,17 @@ public actor DaemonMode: StatusSocket.DataSource {
                 withIntermediateDirectories: true,
                 attributes: [.posixPermissions: 0o700]
             )
-            try FileManager.default.setAttributes(
-                [.posixPermissions: 0o700],
-                ofItemAtPath: config.stateDir.path
-            )
+            let fd = config.stateDir.withUnsafeFileSystemRepresentation { pathPtr -> Int32 in
+                guard let pathPtr = pathPtr else { return -1 }
+                return open(pathPtr, O_RDONLY | O_NOFOLLOW | O_DIRECTORY | O_CLOEXEC)
+            }
+            guard fd >= 0 else {
+                throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno), userInfo: nil)
+            }
+            defer { close(fd) }
+            guard fchmod(fd, 0o700) == 0 else {
+                throw NSError(domain: NSPOSIXErrorDomain, code: Int(errno), userInfo: nil)
+            }
         } catch {
             logger.error("Failed to create/secure state directory: \(error.localizedDescription, privacy: .public)")
             Foundation.exit(1)