From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 80C8AC7618B for ; Fri, 26 Jul 2019 13:40:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A38B22BE8 for ; Fri, 26 Jul 2019 13:40:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148421; bh=cSdDVAIWMsnBNzx9dEUvgtuT/rNZt3Ev+e8xCa6Ol8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ICW51gjM2AGakiQJ5BluwYpTesELd10ATfoJhNxRIMPWFCUMkx6z+2DoxhaJY3E/e spT5b6pSUHEw9ZqVsby4jhjxZcvU5J8HDNu9P7CWz+a3mHG3TnxE8Sh6yLFgcn9tPt 2z/hL6iGQCWdTf2a1fHH8RMMkH5Uz1eCxUjsNCGE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387422AbfGZNkU (ORCPT ); Fri, 26 Jul 2019 09:40:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:46312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726959AbfGZNkS (ORCPT ); Fri, 26 Jul 2019 09:40:18 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id F31A122BF5; Fri, 26 Jul 2019 13:40:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564148417; bh=cSdDVAIWMsnBNzx9dEUvgtuT/rNZt3Ev+e8xCa6Ol8U=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=A40AYqqPiKbbjaKQ3Sz2wdiI+4zVB7ocSjjRjCPjQuDxXcPxA89Yz/GctyMSW5au4 U3CHQ4+mII1GLtNuLYoCNcazQzNmyY9ETGfBmuubMvaKT+uDiWuT0qPk696PyUKEO7 sfsr7fm2P3rPUQUWAqugkwR8jiqAj9JTrEDfoHqA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Russell King , Al Viro , Sasha Levin Subject: [PATCH AUTOSEL 5.2 23/85] fs/adfs: super: fix use-after-free bug Date: Fri, 26 Jul 2019 09:38:33 -0400 Message-Id: <20190726133936.11177-23-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190726133936.11177-1-sashal@kernel.org> References: <20190726133936.11177-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Russell King [ Upstream commit 5808b14a1f52554de612fee85ef517199855e310 ] Fix a use-after-free bug during filesystem initialisation, where we access the disc record (which is stored in a buffer) after we have released the buffer. Signed-off-by: Russell King Signed-off-by: Al Viro Signed-off-by: Sasha Levin --- fs/adfs/super.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/adfs/super.c b/fs/adfs/super.c index ffb669f9bba7..ce0fbbe002bf 100644 --- a/fs/adfs/super.c +++ b/fs/adfs/super.c @@ -360,6 +360,7 @@ static int adfs_fill_super(struct super_block *sb, void *data, int silent) struct buffer_head *bh; struct object_info root_obj; unsigned char *b_data; + unsigned int blocksize; struct adfs_sb_info *asb; struct inode *root; int ret = -EINVAL; @@ -411,8 +412,10 @@ static int adfs_fill_super(struct super_block *sb, void *data, int silent) goto error_free_bh; } + blocksize = 1 << dr->log2secsize; brelse(bh); - if (sb_set_blocksize(sb, 1 << dr->log2secsize)) { + + if (sb_set_blocksize(sb, blocksize)) { bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize); if (!bh) { adfs_error(sb, "couldn't read superblock on " -- 2.20.1