From patchwork Wed Dec 16 23:39:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Paul Cercueil X-Patchwork-Id: 344904 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 10697C4361B for ; Wed, 16 Dec 2020 23:41:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D850223403 for ; Wed, 16 Dec 2020 23:41:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729391AbgLPXku (ORCPT ); Wed, 16 Dec 2020 18:40:50 -0500 Received: from aposti.net ([89.234.176.197]:42568 "EHLO aposti.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727769AbgLPXkt (ORCPT ); Wed, 16 Dec 2020 18:40:49 -0500 From: Paul Cercueil To: Thomas Bogendoerfer Cc: Nathan Chancellor , Nick Desaulniers , od@zcrc.me, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Paul Cercueil , stable@vger.kernel.org Subject: [PATCH] MIPS: boot: Fix unaligned access with CONFIG_MIPS_RAW_APPENDED_DTB Date: Wed, 16 Dec 2020 23:39:56 +0000 Message-Id: <20201216233956.280068-1-paul@crapouillou.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The compressed payload is not necesarily 4-byte aligned, at least when compiling with Clang. In that case, the 4-byte value appended to the compressed payload that corresponds to the uncompressed kernel image size must be read using get_unaligned_le(). This fixes Clang-built kernels not booting on MIPS (tested on a Ingenic JZ4770 board). Fixes: b8f54f2cde78 ("MIPS: ZBOOT: copy appended dtb to the end of the kernel") Cc: # v4.7 Signed-off-by: Paul Cercueil Reviewed-by: Nick Desaulniers Reviewed-by: Philippe Mathieu-Daudé --- arch/mips/boot/compressed/decompress.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c index c61c641674e6..47c07990432b 100644 --- a/arch/mips/boot/compressed/decompress.c +++ b/arch/mips/boot/compressed/decompress.c @@ -117,7 +117,7 @@ void decompress_kernel(unsigned long boot_heap_start) dtb_size = fdt_totalsize((void *)&__appended_dtb); /* last four bytes is always image size in little endian */ - image_size = le32_to_cpup((void *)&__image_end - 4); + image_size = get_unaligned_le32((void *)&__image_end - 4); /* copy dtb to where the booted kernel will expect it */ memcpy((void *)VMLINUX_LOAD_ADDRESS_ULL + image_size,