[php-src] PHP-8.4: Add a stack limit check in php_array_replace_recursive (#23124)

Author: Lazizbek Ergashev (lazerg) Committer: GitHub (web-flow) Pusher: arnaud-lb Date: 2026-08-10T11:59:11+02:00 Commit: https://github.com/php/php-src/commit/af1abdfc34b0f4fb0ad9cfef5533a989bc4a02ab Raw diff: https://github.com/php/php-src/commit/af1abdfc34b0f4fb0ad9cfef5533a989bc4a02ab.diff Add a stack limit check in php_array_replace_recursive (#23124) php_array_replace_recursive() recurses once per nesting level with no stack check, so array_replace_recursive() on a deeply nested array exhausts the native stack and the process dies with a segfault. Fixes GH-23113 Changed paths: A ext/standard/tests/array/gh23113.phpt M NEWS M ext/standard/array.c Diff: diff --git a/NEWS b/NEWS index 01eb4160a20a..d7dadb551bcb 100644 --- a/NEWS +++ b/NEWS @@ -72,6 +72,8 @@ PHP NEWS - Standard: . Fixed bug GH-23111 (Stack overflow in array_walk_recursive() with deeply nested arrays). (Lazizbek Ergashev) + . Fixed bug GH-23113 (Stack overflow in array_replace_recursive() with deeply + nested arrays). (Lazizbek Ergashev) - Streams: . Fixed bug GH-15836 (Use-after-free when a user stream filter accesses diff --git a/ext/standard/array.c b/ext/standard/array.c index 6863586c81ff..41123d43bcc6 100644 --- a/ext/standard/array.c +++ b/ext/standard/array.c @@ -4168,6 +4168,13 @@ PHPAPI int php_array_replace_recursive(HashTable *dest, HashTable *src) /* {{{ * zend_ulong num_key; int ret; +#ifdef ZEND_CHECK_STACK_LIMIT + if (UNEXPECTED(zend_call_stack_overflowed(EG(stack_limit)))) { + zend_call_stack_size_error(); + return 0; + } +#endif + ZEND_HASH_FOREACH_KEY_VAL(src, num_key, string_key, src_entry) { src_zval = src_entry; ZVAL_DEREF(src_zval); diff --git a/ext/standard/tests/array/gh23113.phpt b/ext/standard/tests/array/gh23113.phpt new file mode 100644 index 000000000000..894e8d971e53 --- /dev/null +++ b/ext/standard/tests/array/gh23113.phpt @@ -0,0 +1,27 @@ +--TEST-- +GH-23113 (Stack overflow in array_replace_recursive with deeply nested arrays) +--SKIPIF-- +<?php +if (ini_get('zend.max_allowed_stack_size') === false) { + die('skip No stack limit support'); +} +if (getenv('SKIP_ASAN')) { + die('skip ASAN needs different stack limit setting due to more stack space usage'); +} +?> +--INI-- +zend.max_allowed_stack_size=256K +--FILE-- +<?php +$a = []; +for ($i = 0; $i < 30000; $i++) { + $a = ['k' => $a]; +} +try { + array_replace_recursive($a, $a); +} catch (Throwable $e) { + echo $e::class, ": ", $e->getMessage(), "\n"; +} +?> +--EXPECTF-- +Error: Maximum call stack size of %d bytes (zend.max_allowed_stack_size - zend.reserved_stack_size) reached. Infinite recursion?