[php-src] PR #24242: ext/phar: 32-bit/64-bit divergence parsing tar entries with size ≥ 2 GiB (uint32_t → zend_off_t)

Pull Request: https://github.com/php/php-src/pull/24242 Author: PavlNekrasov **Description:** The tar header's size field is read as uint32_t and passed as-is to php_stream_seek() (offset is signed zend_off_t). On 32-bit, zend_off_t is int32, so sizes with the high bit set wrap into a negative offset — UBSan flags it, getSize() returns a negative value, and the corrupt/truncated check never triggers. On 64-bit the same size fits and the entry is correctly rejected as truncated. **Reproducer:** ```sh php -d display_errors=1 -r ' var_dump(PHP_INT_SIZE); try { $phar = new PharData("/test.tar"); echo "Parsed, entries: ", count($phar), PHP_EOL; foreach ($phar as $file) { echo "Name: ", $file->getFilename(), PHP_EOL; echo "Size: ", $file->getSize(), PHP_EOL; echo "Path: ", $file->getPathname(), PHP_EOL; echo "RealPath: ", $file->getRealPath(), PHP_EOL; echo "Readable: ", var_export($file->isReadable(), true), PHP_EOL; echo "--- content (first 64 bytes) ---", PHP_EOL; $fp = $file->openFile("r"); echo bin2hex($fp->fread(64)), PHP_EOL; } } catch (Throwable $e) { echo get_class($e), ": ", $e->getMessage(), PHP_EOL; }' ``` With test.tar (entry bigfile, header size 0xC0000000 = 3221225472): **32-bit:** ``` int(4) Parsed, entries: 1 Name: bigfile Size: -1073741824 Path: phar:///test.tar/bigfile RealPath: Readable: true ``` UBSan: ``` # SUMMARY: UndefinedBehaviorSanitizer: undefined-behavior /php-8.3.31/ext/phar/tar.c:576:21 # /php-8.3.31/ext/phar/tar.c:581:4: runtime error: implicit conversion from type 'uint32_t' (aka 'unsigned int') of value 3221225472 (32-bit, unsigned) to type 'zend_off_t' (aka 'int') changed the value to -1073741824 (32-bit, signed) ``` **64-bit:** ``` int(8) UnexpectedValueException: phar error: "/host/test.tar" is a corrupted tar file (truncated) ``` **Env:** PHP 8.3.31; 32-bit and 64-bit builds. Found by Linux Verification Center (linuxtesting.org) with SVACE