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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 A19FEC2BA19 for ; Thu, 23 Apr 2020 23:24:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 814562077D for ; Thu, 23 Apr 2020 23:24:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729985AbgDWXYM (ORCPT ); Thu, 23 Apr 2020 19:24:12 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48326 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728155AbgDWXGa (ORCPT ); Thu, 23 Apr 2020 19:06:30 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jRkvK-0004ai-38; Fri, 24 Apr 2020 00:06:26 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jRkvJ-00E6hF-2G; Fri, 24 Apr 2020 00:06:25 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "David Sterba" , "Greg Kroah-Hartman" , "Ben Hutchings" , "Nikolay Borisov" , "Qu Wenruo" Date: Fri, 24 Apr 2020 00:04:26 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 039/245] btrfs: Check if item pointer overlaps with the item itself In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Qu Wenruo commit 7f43d4affb2a254d421ab20b0cf65ac2569909fb upstream. Function check_leaf() checks if any item pointer points outside of the leaf, but it doesn't check if the pointer overlaps with the item itself. Normally only the last item may be the victim, but adding such check is never a bad idea anyway. Signed-off-by: Qu Wenruo Reviewed-by: Nikolay Borisov Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- fs/btrfs/disk-io.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -606,6 +606,13 @@ static noinline int check_leaf(struct bt return -EUCLEAN; } + /* Also check if the item pointer overlaps with btrfs item. */ + if (btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item) > + btrfs_item_ptr_offset(leaf, slot)) { + CORRUPT("slot overlap with its data", leaf, root, slot); + return -EUCLEAN; + } + prev_key.objectid = key.objectid; prev_key.type = key.type; prev_key.offset = key.offset;