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=-10.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 7938EC433E7 for ; Mon, 20 Jul 2020 16:03:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 555E92176B for ; Mon, 20 Jul 2020 16:03:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595261005; bh=Z9eIgK61mjS4Ul2PRXMOZ1S4VcotxUTrQE+5+4dWKuk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=wipDwPGaYzHaV+MO0FqImfjNWYwrd/6OxP51skMnkCTYk0wvX23qyc/xhy9Fv9w7V UFCk8xmEL/iqOEX4olJmsxIJqUQ7UtOnoBqrZFrcechbIDhOWY7/ifAacgnieKDBr5 Se9Kq1bTNxVnl5A0GFG+UIOuPr+M8gHIhtAZNgA8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732441AbgGTQDX (ORCPT ); Mon, 20 Jul 2020 12:03:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:37614 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732425AbgGTQDT (ORCPT ); Mon, 20 Jul 2020 12:03:19 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A6B9E20672; Mon, 20 Jul 2020 16:03:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1595260999; bh=Z9eIgK61mjS4Ul2PRXMOZ1S4VcotxUTrQE+5+4dWKuk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m128PxrXx8FKh8jM6YB2Spm6E0Yb3phMNIeaRcWzpuZSCnwviVw6Eq2JkPvaWGjW7 N7WOTx92FPlDinoNFyTxq0M2KYcYF4mflCk6bTw0ckXh30KqA7WSLJqw+dt3SHYWsz +U1UaZSi0xfiarj/Gtx+v34I7WSyoJHqeIQrDhYQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stefan Priebe , Miklos Szeredi Subject: [PATCH 5.4 173/215] fuse: ignore data argument of mount(..., MS_REMOUNT) Date: Mon, 20 Jul 2020 17:37:35 +0200 Message-Id: <20200720152828.408019065@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200720152820.122442056@linuxfoundation.org> References: <20200720152820.122442056@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Miklos Szeredi commit e8b20a474cf2c42698d1942f939ff2128819f151 upstream. The command mount -o remount -o unknownoption /mnt/fuse succeeds on kernel versions prior to v5.4 and fails on kernel version at or after. This is because fuse_parse_param() rejects any unrecognised options in case of FS_CONTEXT_FOR_RECONFIGURE, just as for FS_CONTEXT_FOR_MOUNT. This causes a regression in case the fuse filesystem is in fstab, since remount sends all options found there to the kernel; even ones that are meant for the initial mount and are consumed by the userspace fuse server. Fix this by ignoring mount options, just as fuse_remount_fs() did prior to the conversion to the new API. Reported-by: Stefan Priebe Fixes: c30da2e981a7 ("fuse: convert to use the new mount API") Cc: # v5.4 Signed-off-by: Miklos Szeredi Signed-off-by: Greg Kroah-Hartman --- fs/fuse/inode.c | 7 +++++++ 1 file changed, 7 insertions(+) --- a/fs/fuse/inode.c +++ b/fs/fuse/inode.c @@ -473,6 +473,13 @@ static int fuse_parse_param(struct fs_co struct fuse_fs_context *ctx = fc->fs_private; int opt; + /* + * Ignore options coming from mount(MS_REMOUNT) for backward + * compatibility. + */ + if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) + return 0; + opt = fs_parse(fc, &fuse_fs_parameters, param, &result); if (opt < 0) return opt;