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 D554EC04A6A for ; Tue, 25 Jul 2023 10:54:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232047AbjGYKyK (ORCPT ); Tue, 25 Jul 2023 06:54:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58406 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233826AbjGYKx2 (ORCPT ); Tue, 25 Jul 2023 06:53:28 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3BCF2113 for ; Tue, 25 Jul 2023 03:51:59 -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 77D4761691 for ; Tue, 25 Jul 2023 10:51:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 839B4C433CB; Tue, 25 Jul 2023 10:51:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1690282318; bh=ZOoUxsDyKwEulenjDn/1naBRUgbYK9tIpKiPvo2Coh8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q6POmwAz2Mo3cWdy3vezZooG8Gn9lVLqsbotnY5Ys928EucylNtUSOB0PW5PiMJ24 doXrjM62uMeAUznZZHiNDJchuoTqPS9gJpzag9QpS/fbsMLjqxmgJlVEfCCiRnPlml T+bDDeHS4ovEmIr97rvvdy6XRKaDmKRLLxw9H1yU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+f1faa20eec55e0c8644c@syzkaller.appspotmail.com, Immad Mir , Dave Kleikamp , Sasha Levin Subject: [PATCH 6.4 086/227] [PATCH AUTOSEL 5.4 11/12] FS: JFS: Fix null-ptr-deref Read in txBegin Date: Tue, 25 Jul 2023 12:44:13 +0200 Message-ID: <20230725104518.302403587@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230725104514.821564989@linuxfoundation.org> References: <20230725104514.821564989@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 [ Upstream commit 47cfdc338d674d38f4b2f22b7612cc6a2763ba27 ] Syzkaller reported an issue where txBegin may be called on a superblock in a read-only mounted filesystem which leads to NULL pointer deref. This could be solved by checking if the filesystem is read-only before calling txBegin, and returning with appropiate error code. Reported-By: syzbot+f1faa20eec55e0c8644c@syzkaller.appspotmail.com Link: https://syzkaller.appspot.com/bug?id=be7e52c50c5182cc09a09ea6fc456446b2039de3 Signed-off-by: Immad Mir Signed-off-by: Dave Kleikamp Signed-off-by: Sasha Levin --- fs/jfs/namei.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/fs/jfs/namei.c +++ b/fs/jfs/namei.c @@ -799,6 +799,11 @@ static int jfs_link(struct dentry *old_d if (rc) goto out; + if (isReadOnly(ip)) { + jfs_error(ip->i_sb, "read-only filesystem\n"); + return -EROFS; + } + tid = txBegin(ip->i_sb, 0); mutex_lock_nested(&JFS_IP(dir)->commit_mutex, COMMIT_MUTEX_PARENT);