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 9CDF0C433FE for ; Sun, 9 Oct 2022 06:23:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229788AbiJIGXg (ORCPT ); Sun, 9 Oct 2022 02:23:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52984 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229469AbiJIGXf (ORCPT ); Sun, 9 Oct 2022 02:23:35 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CC2D02B60A for ; Sat, 8 Oct 2022 23:23:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1665296612; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZeEFM2g1KPCSHqVKEIXgHCa1SGCHP1tlBoS23cVoXoQ=; b=bM0p4Vz8w4piyVps0bLCWd25no6z6G2J61MOdbt1Y8MfmUcxCHn8xt+5MtfP79kMy6z0aM q2UEdEttEh1CozTH+uxrop2V5ilkjivzck1K05L9rZStEph3tSAeTdBLhtk8A9b0sOObZG Ib3Lpvx36rkxJP4k3RVBm+2Wjmc42kk= Received: from mail-pl1-f200.google.com (mail-pl1-f200.google.com [209.85.214.200]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-21-ReajxqilMTqKYzwABJuMpw-1; Sun, 09 Oct 2022 02:23:30 -0400 X-MC-Unique: ReajxqilMTqKYzwABJuMpw-1 Received: by mail-pl1-f200.google.com with SMTP id n10-20020a170902e54a00b001782663dcaeso6101743plf.18 for ; Sat, 08 Oct 2022 23:23:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-language:content-transfer-encoding:in-reply-to:mime-version :user-agent:date:message-id:from:references:cc:to:subject :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ZeEFM2g1KPCSHqVKEIXgHCa1SGCHP1tlBoS23cVoXoQ=; b=2BSk9sM1AQz21puDqElcab4Vg/wOq4ddcxPUgryTU7kHt5n6I1o+Du2JLvcSsAUQ/o KWaN8dQ2PQPwLXndoY20vsgSRrfpGqZ8sMguO0AbyVhBhasNixR2VSffTUZLvhn/jW0R tEQPaeinc0hE+t+ZxsEv+8GNTKf0XIQcRGxDDg5tRIHYpUdqPRhRiOZadjFdvv4wnC1l Di/p2gbIMaHxDnJQkp6JxfKX5/tLuyzRdlvzpotktPbYFtxvIwycHf50DEdQUEBPoPL+ e/r+GbpzB1Wgux4HqfYjZJX+odn8n3sUoNQwtsYvhiwVhEFjYfF2olkNCm3FlrFhJtcl 4p4g== X-Gm-Message-State: ACrzQf1TEHfIvyXbWPRGo6vSlwiDBaU/Of/3s1yIsKZFCajsA5ikGLJr Catnni+6p5BFcAWwdXR0ptIapCscMSssPoU3IchfVEfD8V8BtyyrjRk5x5qklz6ACHYcDUU6lnl 92ejPR7O8ne8U+Q7VenuTqA== X-Received: by 2002:a63:4a0f:0:b0:44e:4323:e884 with SMTP id x15-20020a634a0f000000b0044e4323e884mr11426590pga.225.1665296609604; Sat, 08 Oct 2022 23:23:29 -0700 (PDT) X-Google-Smtp-Source: AMsMyM7xp0jYYr9UUcKpw1u8A7gU32yhxwFcwpyRvW1olwP3TFl33ABl90NqKJXeWXBAkcER/Mpt0g== X-Received: by 2002:a63:4a0f:0:b0:44e:4323:e884 with SMTP id x15-20020a634a0f000000b0044e4323e884mr11426575pga.225.1665296609275; Sat, 08 Oct 2022 23:23:29 -0700 (PDT) Received: from [10.72.12.247] ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id d5-20020a17090a2a4500b001f2ef3c7956sm6994409pjg.25.2022.10.08.23.23.26 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 08 Oct 2022 23:23:28 -0700 (PDT) Subject: Re: [PATCH] fs/ceph/super: add mount options "snapdir{mode,uid,gid}" To: Max Kellermann , idryomov@gmail.com, jlayton@kernel.org, ceph-devel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220927120857.639461-1-max.kellermann@ionos.com> From: Xiubo Li Message-ID: <88f8941f-82bf-5152-b49a-56cb2e465abb@redhat.com> Date: Sun, 9 Oct 2022 14:23:22 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20220927120857.639461-1-max.kellermann@ionos.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: ceph-devel@vger.kernel.org Hi Max, Sorry for late and just back from a long vocation. On 27/09/2022 20:08, Max Kellermann wrote: > By default, the ".snap" directory inherits the parent's permissions > and ownership, which allows all users to create new cephfs snapshots > in arbitrary directories they have write access on. > > In some environments, giving everybody this capability is not > desirable, but there is currently no way to disallow only some users > to create snapshots. It is only possible to revoke the permission to > the whole client (i.e. all users on the computer which mounts the > cephfs). > > This patch allows overriding the permissions and ownership of all > virtual ".snap" directories in a cephfs mount, which allows > restricting (read and write) access to snapshots. > > For example, the mount options: > > snapdirmode=0751,snapdiruid=0,snapdirgid=4 > > ... allows only user "root" to create or delete snapshots, and group > "adm" (gid=4) is allowed to get a list of snapshots. All others are > allowed to read the contents of existing snapshots (if they know the > name). I don't think this is a good place to implement this in client side. Should this be a feature in cephx. With this for the same directories in different mounts will behave differently. Isn't that odd ? -- Xiubo > Signed-off-by: Max Kellermann > --- > fs/ceph/inode.c | 7 ++++--- > fs/ceph/super.c | 33 +++++++++++++++++++++++++++++++++ > fs/ceph/super.h | 4 ++++ > 3 files changed, 41 insertions(+), 3 deletions(-) > > diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c > index 56c53ab3618e..0e9388af2821 100644 > --- a/fs/ceph/inode.c > +++ b/fs/ceph/inode.c > @@ -80,6 +80,7 @@ struct inode *ceph_get_snapdir(struct inode *parent) > }; > struct inode *inode = ceph_get_inode(parent->i_sb, vino); > struct ceph_inode_info *ci = ceph_inode(inode); > + struct ceph_mount_options *const fsopt = ceph_inode_to_client(parent)->mount_options; > > if (IS_ERR(inode)) > return inode; > @@ -96,9 +97,9 @@ struct inode *ceph_get_snapdir(struct inode *parent) > goto err; > } > > - inode->i_mode = parent->i_mode; > - inode->i_uid = parent->i_uid; > - inode->i_gid = parent->i_gid; > + inode->i_mode = fsopt->snapdir_mode == (umode_t)-1 ? parent->i_mode : fsopt->snapdir_mode; > + inode->i_uid = uid_eq(fsopt->snapdir_uid, INVALID_UID) ? parent->i_uid : fsopt->snapdir_uid; > + inode->i_gid = gid_eq(fsopt->snapdir_gid, INVALID_GID) ? parent->i_gid : fsopt->snapdir_gid; > inode->i_mtime = parent->i_mtime; > inode->i_ctime = parent->i_ctime; > inode->i_atime = parent->i_atime; > diff --git a/fs/ceph/super.c b/fs/ceph/super.c > index 40140805bdcf..5e5713946f7b 100644 > --- a/fs/ceph/super.c > +++ b/fs/ceph/super.c > @@ -143,6 +143,9 @@ enum { > Opt_readdir_max_entries, > Opt_readdir_max_bytes, > Opt_congestion_kb, > + Opt_snapdirmode, > + Opt_snapdiruid, > + Opt_snapdirgid, > /* int args above */ > Opt_snapdirname, > Opt_mds_namespace, > @@ -200,6 +203,9 @@ static const struct fs_parameter_spec ceph_mount_parameters[] = { > fsparam_flag_no ("require_active_mds", Opt_require_active_mds), > fsparam_u32 ("rsize", Opt_rsize), > fsparam_string ("snapdirname", Opt_snapdirname), > + fsparam_u32oct ("snapdirmode", Opt_snapdirmode), > + fsparam_u32 ("snapdiruid", Opt_snapdiruid), > + fsparam_u32 ("snapdirgid", Opt_snapdirgid), > fsparam_string ("source", Opt_source), > fsparam_string ("mon_addr", Opt_mon_addr), > fsparam_u32 ("wsize", Opt_wsize), > @@ -414,6 +420,22 @@ static int ceph_parse_mount_param(struct fs_context *fc, > fsopt->snapdir_name = param->string; > param->string = NULL; > break; > + case Opt_snapdirmode: > + fsopt->snapdir_mode = result.uint_32; > + if (fsopt->snapdir_mode & ~0777) > + return invalfc(fc, "Invalid snapdirmode"); > + fsopt->snapdir_mode |= S_IFDIR; > + break; > + case Opt_snapdiruid: > + fsopt->snapdir_uid = make_kuid(current_user_ns(), result.uint_32); > + if (!uid_valid(fsopt->snapdir_uid)) > + return invalfc(fc, "Invalid snapdiruid"); > + break; > + case Opt_snapdirgid: > + fsopt->snapdir_gid = make_kgid(current_user_ns(), result.uint_32); > + if (!gid_valid(fsopt->snapdir_gid)) > + return invalfc(fc, "Invalid snapdirgid"); > + break; > case Opt_mds_namespace: > if (!namespace_equals(fsopt, param->string, strlen(param->string))) > return invalfc(fc, "Mismatching mds_namespace"); > @@ -734,6 +756,14 @@ static int ceph_show_options(struct seq_file *m, struct dentry *root) > seq_printf(m, ",readdir_max_bytes=%u", fsopt->max_readdir_bytes); > if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT)) > seq_show_option(m, "snapdirname", fsopt->snapdir_name); > + if (fsopt->snapdir_mode != (umode_t)-1) > + seq_printf(m, ",snapdirmode=%o", fsopt->snapdir_mode); > + if (!uid_eq(fsopt->snapdir_uid, INVALID_UID)) > + seq_printf(m, ",snapdiruid=%o", > + from_kuid_munged(&init_user_ns, fsopt->snapdir_uid)); > + if (!gid_eq(fsopt->snapdir_gid, INVALID_GID)) > + seq_printf(m, ",snapdirgid=%o", > + from_kgid_munged(&init_user_ns, fsopt->snapdir_gid)); > > return 0; > } > @@ -1335,6 +1365,9 @@ static int ceph_init_fs_context(struct fs_context *fc) > fsopt->wsize = CEPH_MAX_WRITE_SIZE; > fsopt->rsize = CEPH_MAX_READ_SIZE; > fsopt->rasize = CEPH_RASIZE_DEFAULT; > + fsopt->snapdir_mode = (umode_t)-1; > + fsopt->snapdir_uid = INVALID_UID; > + fsopt->snapdir_gid = INVALID_GID; > fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL); > if (!fsopt->snapdir_name) > goto nomem; > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > index d44a366b2f1b..3c930816078d 100644 > --- a/fs/ceph/super.h > +++ b/fs/ceph/super.h > @@ -85,6 +85,10 @@ struct ceph_mount_options { > unsigned int max_readdir; /* max readdir result (entries) */ > unsigned int max_readdir_bytes; /* max readdir result (bytes) */ > > + umode_t snapdir_mode; > + kuid_t snapdir_uid; > + kgid_t snapdir_gid; > + > bool new_dev_syntax; > > /*