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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 1BF77C433E4 for ; Mon, 17 Aug 2020 17:54:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9FC82063A for ; Mon, 17 Aug 2020 17:54:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597686894; bh=Vz1IWgRRXlQKFbJAubLEj5+gx2dz54XngUGfMWWbNtA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jsGjU0QYFVqkrJFXGQxxy/LWAq7Rpl/5rO+oFg2j9KwatzQmm3aTxkgISUwcbft8G Ue8PLVr+YuXCjJSvG0QKfN+InR839IR+ZUQjG89Uy+18TsFFXoFbd13Ko1mhUtH4AP V/fAAUCjBMyCjpg6rPg4pvCJ62PKSGRq+KDTKV8E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731707AbgHQRyw (ORCPT ); Mon, 17 Aug 2020 13:54:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:38200 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388577AbgHQQKz (ORCPT ); Mon, 17 Aug 2020 12:10:55 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5C9BE22D3E; Mon, 17 Aug 2020 16:10:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680654; bh=Vz1IWgRRXlQKFbJAubLEj5+gx2dz54XngUGfMWWbNtA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=mvvdsCJ8ZbxDF10SsWWoGIS+GKpHY4pP/DJBn+j3s6CNvq7PV+p0I/X4zPwDM4o+g QwZOyUNS7yYieZ7DQ8GwmGp9XSobsUXRl9xqsqkebbNNV5aKa/175cYmUlQPhg9jQn feGFegKwWHbK0Sen3n+AaEEkxuSsCn1/ks3e2oa0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+4a88b2b9dc280f47baf4@syzkaller.appspotmail.com, Eric Biggers , Andrew Morton , Qiujun Huang , Alexander Viro , Linus Torvalds Subject: [PATCH 5.4 262/270] fs/minix: check return value of sb_getblk() Date: Mon, 17 Aug 2020 17:17:43 +0200 Message-Id: <20200817143808.868521773@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143755.807583758@linuxfoundation.org> References: <20200817143755.807583758@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eric Biggers commit da27e0a0e5f655f0d58d4e153c3182bb2b290f64 upstream. Patch series "fs/minix: fix syzbot bugs and set s_maxbytes". This series fixes all syzbot bugs in the minix filesystem: KASAN: null-ptr-deref Write in get_block KASAN: use-after-free Write in get_block KASAN: use-after-free Read in get_block WARNING in inc_nlink KMSAN: uninit-value in get_block WARNING in drop_nlink It also fixes the minix filesystem to set s_maxbytes correctly, so that userspace sees the correct behavior when exceeding the max file size. This patch (of 6): sb_getblk() can fail, so check its return value. This fixes a NULL pointer dereference. Originally from Qiujun Huang. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: syzbot+4a88b2b9dc280f47baf4@syzkaller.appspotmail.com Signed-off-by: Eric Biggers Signed-off-by: Andrew Morton Cc: Qiujun Huang Cc: Alexander Viro Cc: Link: http://lkml.kernel.org/r/20200628060846.682158-1-ebiggers@kernel.org Link: http://lkml.kernel.org/r/20200628060846.682158-2-ebiggers@kernel.org Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/minix/itree_common.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) --- a/fs/minix/itree_common.c +++ b/fs/minix/itree_common.c @@ -75,6 +75,7 @@ static int alloc_branch(struct inode *in int n = 0; int i; int parent = minix_new_block(inode); + int err = -ENOSPC; branch[0].key = cpu_to_block(parent); if (parent) for (n = 1; n < num; n++) { @@ -85,6 +86,11 @@ static int alloc_branch(struct inode *in break; branch[n].key = cpu_to_block(nr); bh = sb_getblk(inode->i_sb, parent); + if (!bh) { + minix_free_block(inode, nr); + err = -ENOMEM; + break; + } lock_buffer(bh); memset(bh->b_data, 0, bh->b_size); branch[n].bh = bh; @@ -103,7 +109,7 @@ static int alloc_branch(struct inode *in bforget(branch[i].bh); for (i = 0; i < n; i++) minix_free_block(inode, block_to_cpu(branch[i].key)); - return -ENOSPC; + return err; } static inline int splice_branch(struct inode *inode,