From ecc0459f763ea4f0294a9ba00e9050aba7fd3907 Mon Sep 17 00:00:00 2001
From: Brian Gianforcaro <bgianf@serenityos.org>
Date: Sun, 27 Mar 2022 15:48:16 -0700
Subject: [PATCH] LibC: Fix potential double free in ttyname_r_for_directory

If we break out of the loop before we attempt to allocate again,
then we double free the memory pointed to by `name_path`.

Found by Static Analysis: Sonar Cloud
---
 Userland/Libraries/LibC/unistd.cpp | 1 +
 1 file changed, 1 insertion(+)

diff --git a/Userland/Libraries/LibC/unistd.cpp b/Userland/Libraries/LibC/unistd.cpp
index c7caea4678..398c44e8f9 100644
--- a/Userland/Libraries/LibC/unistd.cpp
+++ b/Userland/Libraries/LibC/unistd.cpp
@@ -438,6 +438,7 @@ static int ttyname_r_for_directory(const char* directory_name, dev_t device_mode
             struct stat st;
             if (lstat(name_path, &st) < 0) {
                 free(name_path);
+                name_path = nullptr;
                 continue;
             }