From patchwork Tue Nov 9 02:35:25 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrew Morton X-Patchwork-Id: 12609559 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E1FF8C433EF for ; Tue, 9 Nov 2021 02:35:27 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 9AD69614C8 for ; Tue, 9 Nov 2021 02:35:27 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 9AD69614C8 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 3D2D56B00FE; Mon, 8 Nov 2021 21:35:27 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 359DE6B00FF; Mon, 8 Nov 2021 21:35:27 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1FB066B0100; Mon, 8 Nov 2021 21:35:27 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0061.hostedemail.com [216.40.44.61]) by kanga.kvack.org (Postfix) with ESMTP id 0D74C6B00FE for ; Mon, 8 Nov 2021 21:35:27 -0500 (EST) Received: from smtpin08.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id C91C118494E78 for ; Tue, 9 Nov 2021 02:35:26 +0000 (UTC) X-FDA: 78787825452.08.65A0569 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf29.hostedemail.com (Postfix) with ESMTP id 7A86B9001A8F for ; Tue, 9 Nov 2021 02:35:26 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 9E5F3613B3; Tue, 9 Nov 2021 02:35:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1636425325; bh=zAvUZDHqDZu2YjDQJxNNXTrvx08br2IQ9kCYUIG1im4=; h=Date:From:To:Subject:In-Reply-To:From; b=frggdGhRnxfR2596CJtwWorCNvKDID69VG6HAIdTSzmk2GZlAf47sGx+f1clpFhPq lZlwrVMhgBZr61So4Ziyu/eJoFlLrhYGzTnxVeq8Ya9/SMAlWf15NSmbb4k/fM4HVT +/yR51igCkE4PG76i7P5ax5TbA/zVtNEHUO4/1ds= Date: Mon, 08 Nov 2021 18:35:25 -0800 From: Andrew Morton To: akpm@linux-foundation.org, hch@lst.de, linux-mm@kvack.org, mm-commits@vger.kernel.org, paskripkin@gmail.com, torvalds@linux-foundation.org Subject: [patch 75/87] sysv: use BUILD_BUG_ON instead of runtime check Message-ID: <20211109023525.rzIFUModX%akpm@linux-foundation.org> In-Reply-To: <20211108183057.809e428e841088b657a975ec@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 7A86B9001A8F X-Stat-Signature: bushfsy13ooyj1ykzwfifcqikkpkbbrr Authentication-Results: imf29.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b=frggdGhR; spf=pass (imf29.hostedemail.com: domain of akpm@linux-foundation.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org; dmarc=none X-HE-Tag: 1636425326-815417 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Pavel Skripkin Subject: sysv: use BUILD_BUG_ON instead of runtime check There were runtime checks about sizes of struct v7_super_block and struct sysv_inode. If one of these checks fail the kernel will panic. Since these values are known at compile time let's use BUILD_BUG_ON(), because it's a standard mechanism for validation checking at build time Link: https://lkml.kernel.org/r/20210813123020.22971-1-paskripkin@gmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Pavel Skripkin Cc: Christoph Hellwig Signed-off-by: Andrew Morton --- fs/sysv/super.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/fs/sysv/super.c~sysv-use-build_bug_on-instead-of-runtime-check +++ a/fs/sysv/super.c @@ -474,10 +474,8 @@ static int v7_fill_super(struct super_bl struct sysv_sb_info *sbi; struct buffer_head *bh; - if (440 != sizeof (struct v7_super_block)) - panic("V7 FS: bad super-block size"); - if (64 != sizeof (struct sysv_inode)) - panic("sysv fs: bad i-node size"); + BUILD_BUG_ON(sizeof(struct v7_super_block) != 440); + BUILD_BUG_ON(sizeof(struct sysv_inode) != 64); sbi = kzalloc(sizeof(struct sysv_sb_info), GFP_KERNEL); if (!sbi)