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 857DAEB64DC for ; Fri, 21 Jul 2023 16:24:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232833AbjGUQYQ (ORCPT ); Fri, 21 Jul 2023 12:24:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51800 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232813AbjGUQXh (ORCPT ); Fri, 21 Jul 2023 12:23:37 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8E536422F for ; Fri, 21 Jul 2023 09:20:30 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 2082461D39 for ; Fri, 21 Jul 2023 16:20:30 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 26F79C43140; Fri, 21 Jul 2023 16:20:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689956429; bh=PX000U1omiXGjurskrbDWLCkoEUtNBAG2bzqTT0cDuE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=TtGEIL3KtFTd4o59eqdbDvGAbIsy1ZTbZiulkOUjwpzjRY/cDIhulnHDmUNnRyiDd BoqPPPy832V0K2O5MqoyEPApnwnrcOBa/3uXqOm5WLy8vk0NGOAFJy3yE9vUpX5bfA tHmZffsA+w/4/MLtdAoPBCYmTk7dVJ9dq/KYWzP0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Dave Kleikamp , Siddh Raman Pant , syzbot+d2cd27dcf8e04b232eb2@syzkaller.appspotmail.com Subject: [PATCH 6.4 162/292] jfs: jfs_dmap: Validate db_l2nbperpage while mounting Date: Fri, 21 Jul 2023 18:04:31 +0200 Message-ID: <20230721160535.867249843@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230721160528.800311148@linuxfoundation.org> References: <20230721160528.800311148@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Siddh Raman Pant commit 11509910c599cbd04585ec35a6d5e1a0053d84c1 upstream. In jfs_dmap.c at line 381, BLKTODMAP is used to get a logical block number inside dbFree(). db_l2nbperpage, which is the log2 number of blocks per page, is passed as an argument to BLKTODMAP which uses it for shifting. Syzbot reported a shift out-of-bounds crash because db_l2nbperpage is too big. This happens because the large value is set without any validation in dbMount() at line 181. Thus, make sure that db_l2nbperpage is correct while mounting. Max number of blocks per page = Page size / Min block size => log2(Max num_block per page) = log2(Page size / Min block size) = log2(Page size) - log2(Min block size) => Max db_l2nbperpage = L2PSIZE - L2MINBLOCKSIZE Reported-and-tested-by: syzbot+d2cd27dcf8e04b232eb2@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?id=2a70a453331db32ed491f5cbb07e81bf2d225715 Cc: stable@vger.kernel.org Suggested-by: Dave Kleikamp Signed-off-by: Siddh Raman Pant Signed-off-by: Dave Kleikamp Signed-off-by: Greg Kroah-Hartman --- fs/jfs/jfs_dmap.c | 6 ++++++ fs/jfs/jfs_filsys.h | 2 ++ 2 files changed, 8 insertions(+) --- a/fs/jfs/jfs_dmap.c +++ b/fs/jfs/jfs_dmap.c @@ -178,7 +178,13 @@ int dbMount(struct inode *ipbmap) dbmp_le = (struct dbmap_disk *) mp->data; bmp->db_mapsize = le64_to_cpu(dbmp_le->dn_mapsize); bmp->db_nfree = le64_to_cpu(dbmp_le->dn_nfree); + bmp->db_l2nbperpage = le32_to_cpu(dbmp_le->dn_l2nbperpage); + if (bmp->db_l2nbperpage > L2PSIZE - L2MINBLOCKSIZE) { + err = -EINVAL; + goto err_release_metapage; + } + bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag); if (!bmp->db_numag) { err = -EINVAL; --- a/fs/jfs/jfs_filsys.h +++ b/fs/jfs/jfs_filsys.h @@ -122,7 +122,9 @@ #define NUM_INODE_PER_IAG INOSPERIAG #define MINBLOCKSIZE 512 +#define L2MINBLOCKSIZE 9 #define MAXBLOCKSIZE 4096 +#define L2MAXBLOCKSIZE 12 #define MAXFILESIZE ((s64)1 << 52) #define JFS_LINK_MAX 0xffffffff