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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 4E0D6C43332 for ; Wed, 30 Dec 2020 13:06:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 38993221FA for ; Wed, 30 Dec 2020 13:06:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727747AbgL3NG1 (ORCPT ); Wed, 30 Dec 2020 08:06:27 -0500 Received: from mail.kernel.org ([198.145.29.99]:53866 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727535AbgL3NFl (ORCPT ); Wed, 30 Dec 2020 08:05:41 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8C579223E0; Wed, 30 Dec 2020 13:04:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1609333492; bh=mWpODWX1cgBx2NaPWjd276b4h5GKAbd0ZaVdJyI/bII=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ebsSkxUKiYEcrMxdOH35kUZIV1ZTf4C4ATomaN0W2555j42OES8V1naB06MtZKaOR yu2w5ffw2R/6sJBMBxP451jXCPD0WC2rYgRT0anNWr/y1yku2R1khxx84QRMGSYhyT 15WCW7o00r/pkSyKLzBGeJ+XN7M9Jkca9fXNQj2z398Ey7QbwSXNP2JEJsLpDao3Xb UEo3BrfgdnchoKTmM5H6UvDXvPNvZ2tizPxe11jOcp2i6LZPznJJOpR1e3MtWu+zyC Xd22hZ2eGU7fpOyoMEnJAL4p5qeLpEhl4n+GYH7GNnyS896147aSbxKwDoTGqtzULD 52bM6/wq/fzNg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Rustam Kovhaev , syzbot+83b6f7cf9922cae5c4d7@syzkaller.appspotmail.com, Jan Kara , Sasha Levin , reiserfs-devel@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 4/5] reiserfs: add check for an invalid ih_entry_count Date: Wed, 30 Dec 2020 08:04:46 -0500 Message-Id: <20201230130447.3637694-4-sashal@kernel.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20201230130447.3637694-1-sashal@kernel.org> References: <20201230130447.3637694-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rustam Kovhaev [ Upstream commit d24396c5290ba8ab04ba505176874c4e04a2d53c ] when directory item has an invalid value set for ih_entry_count it might trigger use-after-free or out-of-bounds read in bin_search_in_dir_item() ih_entry_count * IH_SIZE for directory item should not be larger than ih_item_len Link: https://lore.kernel.org/r/20201101140958.3650143-1-rkovhaev@gmail.com Reported-and-tested-by: syzbot+83b6f7cf9922cae5c4d7@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?extid=83b6f7cf9922cae5c4d7 Signed-off-by: Rustam Kovhaev Signed-off-by: Jan Kara Signed-off-by: Sasha Levin --- fs/reiserfs/stree.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/reiserfs/stree.c b/fs/reiserfs/stree.c index 5f5fff0688776..25b2aed9af0b3 100644 --- a/fs/reiserfs/stree.c +++ b/fs/reiserfs/stree.c @@ -453,6 +453,12 @@ static int is_leaf(char *buf, int blocksize, struct buffer_head *bh) "(second one): %h", ih); return 0; } + if (is_direntry_le_ih(ih) && (ih_item_len(ih) < (ih_entry_count(ih) * IH_SIZE))) { + reiserfs_warning(NULL, "reiserfs-5093", + "item entry count seems wrong %h", + ih); + return 0; + } prev_location = ih_location(ih); } -- 2.27.0