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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21741C433EF for ; Thu, 21 Apr 2022 20:53:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1392597AbiDUU4g (ORCPT ); Thu, 21 Apr 2022 16:56:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36532 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1392581AbiDUU4e (ORCPT ); Thu, 21 Apr 2022 16:56:34 -0400 Received: from mail-lf1-x12c.google.com (mail-lf1-x12c.google.com [IPv6:2a00:1450:4864:20::12c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 33D2F4EA15 for ; Thu, 21 Apr 2022 13:53:44 -0700 (PDT) Received: by mail-lf1-x12c.google.com with SMTP id w1so10798154lfa.4 for ; Thu, 21 Apr 2022 13:53:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QMaXVrKk9gfumVTRL9xZxvAh+Uev5F5t1NCU2kpSj9Y=; b=JgY2opUF0mU6jJmGtfHvRgRMwUOhHike+V7WS9GYAJv9FeWiJLS9GaHBurVKfTpigk wN8dPahuZhpq23Et8iKWCKhJXFl3aTuSWePFXPAscZb6bO/gDWg1dM4wwl7qRy5PLuCx 2voGTpg1P1uhNu4AMkX31N0ZJApoQiBqclQF166RqDTxK6AE5JvYsBZJ4YY0VNXx4nDc CBfFo/Te5JGq4nk95zBSjhH8graeObWF02JcqVfHXd1l53flgQbqjxmqBKMi4iwab9LP 4vMeqWEXhojruavaihjE5vGLmUcKtdUfX4o4C7LG8cjM2F6I3J0E2GrJ/4vNTbCTE25H 4NCw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=QMaXVrKk9gfumVTRL9xZxvAh+Uev5F5t1NCU2kpSj9Y=; b=B7AIrWGOs7Vdrw0tNGEmNgJHciR+9dS/VlZ+R3Zy0KcJtJpoYr+Du51fnen9MZEhB3 OmsxGxs9PWaLtcRArlvuCmpGNVk5PgoHTE9S5TH65hjnU74MkQ0XMLS5Ef+eYzoVhWrh o6s/OYzF4yv5h7QFK1teEse70FwqFu3NYjDGJQp9gxQOGmS7bZ+ExX7Vwb/fyL+dGJ1G ZrKz9SH1BVyKuq0ekGSn2L+b9WGqv+X3s/RK4GN+J2ORLpiXeB+Ba6QE1PHretZAOJva Ir8qWP4tjgjnR5XrAtnjdIxr/68O+uhX1CN2cV4hUoRzssDzCdYYk9J6UfJoRL648CZc 91aQ== X-Gm-Message-State: AOAM533Fs0IWwkGJ7x2Ue8kgfDORzz+JmfNM/hd1ptTkiABD+biWhjmI lyNKue7PNfB4HCCMtgscUPA= X-Google-Smtp-Source: ABdhPJw9myzb07PcFULj//fMjCRC8IEUK0ANDWS8yQnArFiD3LTeE6lCvtrrKb38lDXibyNjWif1EQ== X-Received: by 2002:a19:ee05:0:b0:46e:2f8d:db76 with SMTP id g5-20020a19ee05000000b0046e2f8ddb76mr836068lfb.321.1650574422442; Thu, 21 Apr 2022 13:53:42 -0700 (PDT) Received: from localhost.localdomain ([94.103.225.17]) by smtp.gmail.com with ESMTPSA id q21-20020a05651232b500b0046bacf73c9fsm11963lfe.151.2022.04.21.13.53.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Apr 2022 13:53:42 -0700 (PDT) From: Pavel Skripkin To: almaz.alexandrovich@paragon-software.com, ntfs3@lists.linux.dev, linux-kernel@vger.kernel.org Cc: Pavel Skripkin , syzbot+c95173762127ad76a824@syzkaller.appspotmail.com Subject: [PATCH 1/2] ntfs3: fix NULL deref in ntfs_update_mftmirr Date: Thu, 21 Apr 2022 23:53:36 +0300 Message-Id: <85293dd018cae78e4d48d74ca77710b11eed59ba.1650574393.git.paskripkin@gmail.com> X-Mailer: git-send-email 2.35.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If ntfs_fill_super() wasn't called then sbi->sb will be equal to NULL. Code should check this ptr before dereferencing. Syzbot hit this issue via passing wrong mount param as can be seen from log below Fail log: ntfs3: Unknown parameter 'iochvrset' general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 1 PID: 3589 Comm: syz-executor210 Not tainted 5.18.0-rc3-syzkaller-00016-gb253435746d9 #0 ... Call Trace: put_ntfs+0x1ed/0x2a0 fs/ntfs3/super.c:463 ntfs_fs_free+0x6a/0xe0 fs/ntfs3/super.c:1363 put_fs_context+0x119/0x7a0 fs/fs_context.c:469 do_new_mount+0x2b4/0xad0 fs/namespace.c:3044 do_mount fs/namespace.c:3383 [inline] __do_sys_mount fs/namespace.c:3591 [inline] Fixes: 82cae269cfa9 ("fs/ntfs3: Add initialization of super block") Reported-and-tested-by: syzbot+c95173762127ad76a824@syzkaller.appspotmail.com Signed-off-by: Pavel Skripkin --- fs/ntfs3/fsntfs.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/ntfs3/fsntfs.c b/fs/ntfs3/fsntfs.c index 3de5700a9b83..891125ca6848 100644 --- a/fs/ntfs3/fsntfs.c +++ b/fs/ntfs3/fsntfs.c @@ -831,10 +831,15 @@ int ntfs_update_mftmirr(struct ntfs_sb_info *sbi, int wait) { int err; struct super_block *sb = sbi->sb; - u32 blocksize = sb->s_blocksize; + u32 blocksize; sector_t block1, block2; u32 bytes; + if (!sb) + return -EINVAL; + + blocksize = sb->s_blocksize; + if (!(sbi->flags & NTFS_FLAGS_MFTMIRR)) return 0; -- 2.35.1