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,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 D69DDC433DF for ; Mon, 24 Aug 2020 02:27:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD517206BE for ; Mon, 24 Aug 2020 02:27:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="OFMl3Uth" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728052AbgHXC1u (ORCPT ); Sun, 23 Aug 2020 22:27:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33822 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726737AbgHXC1s (ORCPT ); Sun, 23 Aug 2020 22:27:48 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C463AC061573 for ; Sun, 23 Aug 2020 19:27:48 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id d22so4044790pfn.5 for ; Sun, 23 Aug 2020 19:27:48 -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=3L3z0BK/0uzC9bSt47v3W+rJZ7YzTzBC3wZRD43cnA4=; b=OFMl3Uthl4B0LUygzKyBFNvaulTy/jC3i1c4+bTDhS+JfVlE1Ot+7iTaSa7A0cYIgC ngIdFA0oW+svhPsqZrzb30umSCe5MWJMkhJS4yjbld3ED9HzFpX1nGlrsvbiR4B+wJXx eCNugCTCDvK3W4/59qg2vF7rS4nqF08H7WjKS9KinevEvXDrvdy8PVTPpEna0Ldlyw+x e8YuQQkrobDgmC03rbF1/IA6tX7xWkZz1iclvw+skdbzzyQB0rZNTxDIUWPK4+1ST4dy tuablQUHXJWoNUOGsPFkT3AfZx74sJ4A8Va7o3gzQd0mDKx3UGK8jbzUic764wd8LV89 UesQ== 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=3L3z0BK/0uzC9bSt47v3W+rJZ7YzTzBC3wZRD43cnA4=; b=bS9lXR33Zo/EdhC7snkI1YP0Z9hGtutg30pRy/iK1QPZpg6U31QA2aEL/gsI56sV4d n7XJOYJR8XFqHYqRqV6kenAsjTUP7xyEk8SSkSemWA5YduDD9MjyW5nuiYf3W6s+qFD4 jD8TtwcWEpdmxNfrBjDQ/5vHy9n0jtDTyv3Q2Vk66HjbEU2D44qHJaBJgN9LNc1gOuYu naQYM7PIb3scixKqO7k9/BxMPwNQlDnG6x2l38fHQPXtZk+kkrwrT5eQMkmN3EYBQOAr Nq+ipzISV8XGwut1lJcw0CJR/vxqxmmC5d2Cj/erNgB+P0pkMpOsipoLOI067BWPhrcq xwKQ== X-Gm-Message-State: AOAM530nFIaud54SZ0Xvb3dmOtHbiUx+36w/BtXl820NKIgiIEAE+9Xb naNwuzIWvKB+mMNvq2JbCGY= X-Google-Smtp-Source: ABdhPJyb9yhrzs/jrFLLEvgIMxZj0ZMSN8gXD4KQBV3v3y6+nmtMh7UY7CMcC9THd5nxMtDyrs57Cg== X-Received: by 2002:a63:b24b:: with SMTP id t11mr2123373pgo.233.1598236068198; Sun, 23 Aug 2020 19:27:48 -0700 (PDT) Received: from thinkpad.teksavvy.com (104.36.148.139.aurocloud.com. [104.36.148.139]) by smtp.gmail.com with ESMTPSA id g15sm9413260pfh.70.2020.08.23.19.27.47 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Aug 2020 19:27:47 -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 19:28:04 -0700 Message-Id: <20200824022804.226242-1-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 Acked-by: Anton Altaparmakov --- fs/ntfs/inode.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c index 9bb9f0952b18..caf563981532 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 (le32_to_cpu(m->bytes_allocated) != vol->mft_record_size) { + ntfs_error(sb, "Incorrect mft record size %u in superblock, should be %u.", + le32_to_cpu(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