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=-12.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 3813CC433E1 for ; Sun, 23 Aug 2020 15:22:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13EFB20706 for ; Sun, 23 Aug 2020 15:22:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="CKq4LAxu" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727926AbgHWPVw (ORCPT ); Sun, 23 Aug 2020 11:21:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727018AbgHWPVo (ORCPT ); Sun, 23 Aug 2020 11:21:44 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 25909C061574 for ; Sun, 23 Aug 2020 08:21:43 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id f193so3487242pfa.12 for ; Sun, 23 Aug 2020 08:21:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=9Len0YLjL+1HYVWLhCeiF5ALGuM9sVBgacotYzHDBck=; b=CKq4LAxuP4oo+spy/Sjtq2HUumog5bo0IHYmqEpjVCxC6JkHFtCwsCBMkudgSOlZgC gtoP46ectLgIOopfzu1t32vOnOYo2swQ0Gt8Ct6SkmJ6YfA3hAkKFhOHJISdD0MtvFkv o0HTvXT8d/AGRstup6rRL3A+b3jlv8TV6sGp4TQr7XsmWQE+DW3Otgc7RhGrFpyfhgw1 Obm4jpuWpZxrNb+f4VPnww0sjbFmv2PNqphHnmVvZqhqA8/2vM1dAgxGYiJIaLd3uFV/ cXRHl1A1LvY73Sq0aGMS2xPHvBmBTI/vWu4m9Si+F4+VuNZk5jBMYu9z+o3S5ijfnWkB 82wg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=9Len0YLjL+1HYVWLhCeiF5ALGuM9sVBgacotYzHDBck=; b=dCqV3rh3egYokir4J7lZ55g9U+rGVl846BL2nrmp6Thi0U5eg4fQ8z91Ej272hkU5x Rs7EI/5+UK2+sbeo2RvCJk5BORCL3Ik5t3QPyi+SnNeQEDIyFrQ80DoztYGzz/E8DCVo MqcEh8fM1wdhv7aRntut78dpSwcPsXh+6IximzDbPc3C0Kq00OVTJMiRyyCDgdKSA0bN 4H6CsZkrs0LNnNzgjDy7qSNakjOGkIcmjS22g39YlFDfgaYx/BUTnhBI7r6JqYXG+don J52PCQ1E6We87ALSb1Ysy/7dIbP1OV51k8a9vLDFg2H14wX9UurCrFwbs6jOu7skM65T A8ew== X-Gm-Message-State: AOAM533k3S2M7pM60ZGnBTQUQ3gazMTYwJpwyfsOv/DTZV13hJ4U9Pgv 4Ewb5WN235YbVeW5UPfPyCBGimzX+MqSpA== X-Google-Smtp-Source: ABdhPJynFN6QXBqe/BQZ1PIMKOJQW64sDPaA+7Mon0obiv343TtEITd8Tte5Kxo4hI1j3vshd7m0zg== X-Received: by 2002:aa7:8b01:: with SMTP id f1mr1224840pfd.35.1598196101834; Sun, 23 Aug 2020 08:21:41 -0700 (PDT) Received: from thinkpad.teksavvy.com (104.36.148.139.aurocloud.com. [104.36.148.139]) by smtp.gmail.com with ESMTPSA id g129sm8457637pfb.33.2020.08.23.08.21.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Aug 2020 08:21:41 -0700 (PDT) From: Rustam Kovhaev To: anton@tuxera.com, linux-ntfs-dev@lists.sourceforge.net Cc: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, Rustam Kovhaev Subject: [PATCH] ntfs: add check for mft record size in superblock Date: Sun, 23 Aug 2020 08:21:47 -0700 Message-Id: <20200823152147.55766-1-rkovhaev@gmail.com> X-Mailer: git-send-email 2.28.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org number of bytes allocated for mft record should be equal to the mft record size stored in ntfs superblock as reported by syzbot, userspace might trigger out-of-bounds read by dereferencing ctx->attr in ntfs_attr_find() Reported-and-tested-by: syzbot+aed06913f36eff9b544e@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=aed06913f36eff9b544e Signed-off-by: Rustam Kovhaev --- fs/ntfs/inode.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c index 9bb9f0952b18..6407af7c2e4f 100644 --- a/fs/ntfs/inode.c +++ b/fs/ntfs/inode.c @@ -1810,6 +1810,12 @@ int ntfs_read_inode_mount(struct inode *vi) brelse(bh); } + if (m->bytes_allocated != vol->mft_record_size) { + ntfs_error(sb, "Incorrect mft record size [%u] in superblock, should be [%u].", + m->bytes_allocated, vol->mft_record_size); + goto err_out; + } + /* Apply the mst fixups. */ if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) { /* FIXME: Try to use the $MFTMirr now. */ -- 2.28.0