[Filesystem] Safeguard (sym)link calls

symfony · derrabus · May 20, 2022 · May 19, 2022 · May 20, 2022 · c15028f2d354d0bdc0f34f2d565da3323e6555a5
commit c15028f2d354d0bdc0f34f2d565da3323e6555a5
diff --git a/src/Symfony/Component/Filesystem/Filesystem.php b/src/Symfony/Component/Filesystem/Filesystem.php
@@ -318,6 +318,8 @@ private function isReadable(string $filename): bool
     */
    public function symlink($originDir, $targetDir, $copyOnWindows = false)
    {
+        self::assertFunctionExists('symlink');
+
        if ('\\' === \DIRECTORY_SEPARATOR) {
            $originDir = strtr($originDir, '/', '\\');
            $targetDir = strtr($targetDir, '/', '\\');
@@ -354,6 +356,8 @@ public function symlink($originDir, $targetDir, $copyOnWindows = false)
     */
    public function hardlink($originFile, $targetFiles)
    {
+        self::assertFunctionExists('link');
+
        if (!$this->exists($originFile)) {
            throw new FileNotFoundException(null, 0, null, $originFile);
        }
@@ -737,13 +741,22 @@ private function getSchemeAndHierarchy(string $filename): array
        return 2 === \count($components) ? [$components[0], $components[1]] : [null, $components[0]];
    }

+    private static function assertFunctionExists(string $func): void
+    {
+        if (!\function_exists($func)) {
+            throw new IOException(sprintf('Unable to perform filesystem operation because the "%s()" function has been disabled.', $func));
+        }
+    }
+
    /**
     * @param mixed ...$args
     *
     * @return mixed
     */
-    private static function box(callable $func, ...$args)
+    private static function box(string $func, ...$args)
    {
+        self::assertFunctionExists($func);
+
        self::$lastError = null;
        set_error_handler(__CLASS__.'::handleError');
        try {