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=-16.4 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 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 4C824C4320A for ; Tue, 31 Aug 2021 13:50:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 34EB261027 for ; Tue, 31 Aug 2021 13:50:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239844AbhHaNv3 (ORCPT ); Tue, 31 Aug 2021 09:51:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:44830 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239497AbhHaNv2 (ORCPT ); Tue, 31 Aug 2021 09:51:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id ED7116056B; Tue, 31 Aug 2021 13:50:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1630417833; bh=rNeCPDjGEqSxtZwbzmo/7hA4Mi6mdmhsWNxJxbxaUeU=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=NzMcbVWzufqnDZIW/B8zYbjnV/Ya7NJ7x3SXOiNJeaQ39dCo2G02L1iMxxkG29+VZ yPKi5Ksu/0wLnn19I6XLY3ENdb4j2qk010LSdQ25FwRZp+YJ1OD03pu9LYCnfAnzP/ sEFhF7nXhL7UhfQqhwCXYbciWXrupiwEtja6AgRttMqS7AENpQjVTaU+7nvpWc/7xw 5V4otkjgcOx2IvjR0aElv1CXu1eqxvi2ieCWAr+EccvrGhQHp3yPpEs8JEWs1aWmXy wqBX2fmkyvl5x0vlpAqjepRLAoMe/3r4lz9wzGWiSQgxK0MixUdVLwtt2BoPi2iWMX xXJ0CHKdU9aJg== Message-ID: <7f231e95bd397394eba44c3e346524bac44a069b.camel@kernel.org> Subject: Re: [RFC PATCH v8 09/24] ceph: add ability to set fscrypt_auth via setattr From: Jeff Layton To: Xiubo Li , ceph-devel@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org, linux-fscrypt@vger.kernel.org, dhowells@redhat.com, lhenriques@suse.de, khiremat@redhat.com, ebiggers@kernel.org Date: Tue, 31 Aug 2021 09:50:32 -0400 In-Reply-To: <60291569-aace-cc83-88de-3de24cefb750@redhat.com> References: <20210826162014.73464-1-jlayton@kernel.org> <20210826162014.73464-10-jlayton@kernel.org> <27f6a038-94a6-ec58-c7a5-0fafc2c9d779@redhat.com> <60291569-aace-cc83-88de-3de24cefb750@redhat.com> Content-Type: text/plain; charset="ISO-8859-15" User-Agent: Evolution 3.40.4 (3.40.4-1.fc34) MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-fscrypt@vger.kernel.org On Tue, 2021-08-31 at 21:22 +0800, Xiubo Li wrote: > On 8/31/21 8:43 PM, Jeff Layton wrote: > > On Tue, 2021-08-31 at 13:06 +0800, Xiubo Li wrote: > > > On 8/27/21 12:19 AM, Jeff Layton wrote: > > > > Signed-off-by: Jeff Layton > > > > --- > > > > fs/ceph/acl.c | 4 +-- > > > > fs/ceph/crypto.h | 9 +++++- > > > > fs/ceph/inode.c | 33 ++++++++++++++++++++-- > > > > fs/ceph/mds_client.c | 54 ++++++++++++++++++++++++++++++------ > > > > fs/ceph/mds_client.h | 3 ++ > > > > fs/ceph/super.h | 7 ++++- > > > > include/linux/ceph/ceph_fs.h | 21 ++++++++------ > > > > 7 files changed, 108 insertions(+), 23 deletions(-) > > > > > > > > diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c > > > > index 529af59d9fd3..6e716f142022 100644 > > > > --- a/fs/ceph/acl.c > > > > +++ b/fs/ceph/acl.c > > > > @@ -136,7 +136,7 @@ int ceph_set_acl(struct user_namespace *mnt_userns, struct inode *inode, > > > > newattrs.ia_ctime = current_time(inode); > > > > newattrs.ia_mode = new_mode; > > > > newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; > > > > - ret = __ceph_setattr(inode, &newattrs); > > > > + ret = __ceph_setattr(inode, &newattrs, NULL); > > > > if (ret) > > > > goto out_free; > > > > } > > > > @@ -147,7 +147,7 @@ int ceph_set_acl(struct user_namespace *mnt_userns, struct inode *inode, > > > > newattrs.ia_ctime = old_ctime; > > > > newattrs.ia_mode = old_mode; > > > > newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; > > > > - __ceph_setattr(inode, &newattrs); > > > > + __ceph_setattr(inode, &newattrs, NULL); > > > > } > > > > goto out_free; > > > > } > > > > diff --git a/fs/ceph/crypto.h b/fs/ceph/crypto.h > > > > index 6c3831c57c8d..6dca674f79b8 100644 > > > > --- a/fs/ceph/crypto.h > > > > +++ b/fs/ceph/crypto.h > > > > @@ -14,8 +14,15 @@ struct ceph_fscrypt_auth { > > > > u8 cfa_blob[FSCRYPT_SET_CONTEXT_MAX_SIZE]; > > > > } __packed; > > > > > > > > -#ifdef CONFIG_FS_ENCRYPTION > > > > #define CEPH_FSCRYPT_AUTH_VERSION 1 > > > > +static inline u32 ceph_fscrypt_auth_len(struct ceph_fscrypt_auth *fa) > > > > +{ > > > > + u32 ctxsize = le32_to_cpu(fa->cfa_blob_len); > > > > + > > > > + return offsetof(struct ceph_fscrypt_auth, cfa_blob) + ctxsize; > > > > +} > > > > + > > > > +#ifdef CONFIG_FS_ENCRYPTION > > > > void ceph_fscrypt_set_ops(struct super_block *sb); > > > > > > > > #else /* CONFIG_FS_ENCRYPTION */ > > > > diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c > > > > index a541f5e9c5ed..ae800372e42d 100644 > > > > --- a/fs/ceph/inode.c > > > > +++ b/fs/ceph/inode.c > > > > @@ -2083,7 +2083,7 @@ static const struct inode_operations ceph_symlink_iops = { > > > > .listxattr = ceph_listxattr, > > > > }; > > > > > > > > -int __ceph_setattr(struct inode *inode, struct iattr *attr) > > > > +int __ceph_setattr(struct inode *inode, struct iattr *attr, struct ceph_iattr *cia) > > > > { > > > > struct ceph_inode_info *ci = ceph_inode(inode); > > > > unsigned int ia_valid = attr->ia_valid; > > > > @@ -2124,6 +2124,34 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr) > > > > > > > > dout("setattr %p issued %s\n", inode, ceph_cap_string(issued)); > > > > > > > > + if (cia && cia->fscrypt_auth) { > > > > + u32 len = ceph_fscrypt_auth_len(cia->fscrypt_auth); > > > > + > > > > + if (len > sizeof(*cia->fscrypt_auth)) { > > > > + err = -EINVAL; > > > > + spin_unlock(&ci->i_ceph_lock); > > > > + goto out; > > > > + } > > > > + > > > > + dout("setattr %llx:%llx fscrypt_auth len %u to %u)\n", > > > > + ceph_vinop(inode), ci->fscrypt_auth_len, len); > > > > + > > > > + /* It should never be re-set once set */ > > > > + WARN_ON_ONCE(ci->fscrypt_auth); > > > > + > > > Maybe this should return -EEXIST if already set ? > > > > > I don't know. In general, once the context is set on an inode, we > > shouldn't ever reset it. That said, I think we might need to allow > > admins to override an existing context if it's corrupted. > > > > So, that's the rationale for the WARN_ON_ONCE. The admins should never > > do this under normal circumstances but they do have the ability to > > change it if needed (and we'll see a warning in the logs in that case). > > I may miss some code in the fs/crypto/ layer. > > I readed that once the directory/file has set the policy context, it > will just return 0 if the new one matches the existence, if not match it > will return -EEXIST, or will try to call ceph layer to set it. > > So once this is set, my understanding is that it shouldn't be here ? > Where did you read that? If we have documented semantics we need to follow here, then we should change it to comply with them. > > > > > + if (issued & CEPH_CAP_AUTH_EXCL) { > > > > + dirtied |= CEPH_CAP_AUTH_EXCL; > > > > + kfree(ci->fscrypt_auth); > > > > + ci->fscrypt_auth = (u8 *)cia->fscrypt_auth; > > > > + ci->fscrypt_auth_len = len; > > > > + } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0) { > > > For this, shouldn't we always set the req->r_fscrypt_auth even the > > > "CEPH_CAP_AUTH_SHARED" cap is issued ? > > > > > > Maybe this should be: > > > > > > } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 || !ci->fscrypt_auth) { > > > > > > ?? > > > > > ...or maybe we need to memcmp ci->fscrypt_auth and cia->fscrypt_auth? > > My understanding is that, if the 'As' cap is not issued, that means > maybe another client has been issued the 'Ax' cap. For the current > client, if !ci->fscrypt_auth == true and > > no matter whether the 'As' cap is issued or not it should try to set the > fscrypt_auth to MDS. But this could fail if another client also trying > to set the fscrypt_auth by holding the 'Ax' cap ? > > Or won't the new one override the old context in MDS side ? > The update to the code that I'm testing now looks like this. if (issued & CEPH_CAP_AUTH_EXCL) { dirtied |= CEPH_CAP_AUTH_EXCL; kfree(ci->fscrypt_auth); ci->fscrypt_auth = (u8 *)cia->fscrypt_auth; ci->fscrypt_auth_len = len; } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 || ci->fscrypt_auth_len != len || memcmp(ci->fscrypt_auth, cia->fscrypt_auth, len)) { req->r_fscrypt_auth = cia->fscrypt_auth; mask |= CEPH_SETATTR_FSCRYPT_AUTH; release |= CEPH_CAP_AUTH_SHARED; } cia->fscrypt_auth = NULL; Basically, the logic is: If we have Ax caps, we can do the change locally and eventually flush it to the server in a cap update. If we have As caps then we can skip issuing a SETATTR if nothing actually changed. If we don't have either, then we just have to issue the SETATTR since we can't tell. > > > > > > In any case, you're right that testing for As caps alone is not > > sufficient. I'll fix that up soon. > > > > > > + req->r_fscrypt_auth = cia->fscrypt_auth; > > > > + mask |= CEPH_SETATTR_FSCRYPT_AUTH; > > > > + release |= CEPH_CAP_AUTH_SHARED; > > > > + } > > > > + cia->fscrypt_auth = NULL; > > > > + } > > > > + > > > > if (ia_valid & ATTR_UID) { > > > > dout("setattr %p uid %d -> %d\n", inode, > > > > from_kuid(&init_user_ns, inode->i_uid), > > > > @@ -2284,6 +2312,7 @@ int __ceph_setattr(struct inode *inode, struct iattr *attr) > > > > req->r_stamp = attr->ia_ctime; > > > > err = ceph_mdsc_do_request(mdsc, NULL, req); > > > > } > > > > +out: > > > > dout("setattr %p result=%d (%s locally, %d remote)\n", inode, err, > > > > ceph_cap_string(dirtied), mask); > > > > > > > > @@ -2321,7 +2350,7 @@ int ceph_setattr(struct user_namespace *mnt_userns, struct dentry *dentry, > > > > ceph_quota_is_max_bytes_exceeded(inode, attr->ia_size)) > > > > return -EDQUOT; > > > > > > > > - err = __ceph_setattr(inode, attr); > > > > + err = __ceph_setattr(inode, attr, NULL); > > > > > > > > if (err >= 0 && (attr->ia_valid & ATTR_MODE)) > > > > err = posix_acl_chmod(&init_user_ns, inode, attr->ia_mode); > > > > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c > > > > index 240b53d58dda..449b4e78366e 100644 > > > > --- a/fs/ceph/mds_client.c > > > > +++ b/fs/ceph/mds_client.c > > > > @@ -15,6 +15,7 @@ > > > > > > > > #include "super.h" > > > > #include "mds_client.h" > > > > +#include "crypto.h" > > > > > > > > #include > > > > #include > > > > @@ -927,6 +928,7 @@ void ceph_mdsc_release_request(struct kref *kref) > > > > put_cred(req->r_cred); > > > > if (req->r_pagelist) > > > > ceph_pagelist_release(req->r_pagelist); > > > > + kfree(req->r_fscrypt_auth); > > > > put_request_session(req); > > > > ceph_unreserve_caps(req->r_mdsc, &req->r_caps_reservation); > > > > WARN_ON_ONCE(!list_empty(&req->r_wait)); > > > > @@ -2618,8 +2620,7 @@ static int set_request_path_attr(struct inode *rinode, struct dentry *rdentry, > > > > return r; > > > > } > > > > > > > > -static void encode_timestamp_and_gids(void **p, > > > > - const struct ceph_mds_request *req) > > > > +static void encode_mclientrequest_tail(void **p, const struct ceph_mds_request *req) > > > > { > > > > struct ceph_timespec ts; > > > > int i;16:51 < batrick> done > > > > @@ -2632,6 +2633,20 @@ static void encode_timestamp_and_gids(void **p, > > > > for (i = 0; i < req->r_cred->group_info->ngroups; i++)load more comments (105 replies) > > > > ceph_encode_64(p, from_kgid(&init_user_ns, > > > > req->r_cred->group_info->gid[i])); > > > > + > > > > + /* v5: altname (TODO: skip for now) */load more comments (105 replies) > > > > + ceph_encode_32(p, 0); > > > > + > > > > + /* v6: fscrypt_auth and fscrypt_file */ > > > > + if (req->r_fscrypt_auth) { > > > > + u32 authlen = ceph_fscrypt_auth_len(req->r_fscrypt_auth); > > > > + > > > > + ceph_encode_32(p, authlen); > > > > + ceph_encode_copy(p, req->r_fscrypt_auth, authlen); > > > > + } else { > > > > + ceph_encode_32(p, 0); > > > > + } > > > > + ceph_encode_32(p, 0); // fscrypt_file for now > > > > } > > > > > > > > /* > > > > @@ -2676,12 +2691,14 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, > > > > goto out_free1; > > > > } > > > > > > > > + /* head */ > > > > len = legacy ? sizeof(*head) : sizeof(struct ceph_mds_request_head); > > > > - len += pathlen1 + pathlen2 + 2*(1 + sizeof(u32) + sizeof(u64)) + > > > > - sizeof(struct ceph_timespec); > > > > - len += sizeof(u32) + (sizeof(u64) * req->r_cred->group_info->ngroups); > > > > > > > > - /* calculate (max) length for cap releases */ > > > > + /* filepaths */ > > > > + len += 2 * (1 + sizeof(u32) + sizeof(u64)); > > > > + len += pathlen1 + pathlen2; > > > > + > > > > + /* cap releases */ > > > > len += sizeof(struct ceph_mds_request_release) * > > > > (!!req->r_inode_drop + !!req->r_dentry_drop + > > > > !!req->r_old_inode_drop + !!req->r_old_dentry_drop); > > > > @@ -2691,6 +2708,25 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, > > > > if (req->r_old_dentry_drop) > > > > len += pathlen2; > > > > > > > > + /* MClientRequest tail */ > > > > + > > > > + /* req->r_stamp */ > > > > + len += sizeof(struct ceph_timespec); > > > > + > > > > + /* gid list */ > > > > + len += sizeof(u32) + (sizeof(u64) * req->r_cred->group_info->ngroups); > > > > + > > > > + /* alternate name */ > > > > + len += sizeof(u32); // TODO > > > > + > > > > + /* fscrypt_auth */ > > > > + len += sizeof(u32); // fscrypt_auth > > > > + if (req->r_fscrypt_auth) > > > > + len += ceph_fscrypt_auth_len(req->r_fscrypt_auth); > > > > + > > > > + /* fscrypt_file */ > > > > + len += sizeof(u32); > > > > + > > > > msg = ceph_msg_new2(CEPH_MSG_CLIENT_REQUEST, len, 1, GFP_NOFS, false); > > > > if (!msg) {load more comments (105 replies) > > > > msg = ERR_PTR(-ENOMEM); > > > > @@ -2710,7 +2746,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, > > > > } else { > > > > struct ceph_mds_request_head *new_head = msg->front.iov_base; > > > > > > > > - msg->hdr.version = cpu_to_le16(4); > > > > + msg->hdr.version = cpu_to_le16(6); > > > > new_head->version = cpu_to_le16(CEPH_MDS_REQUEST_HEAD_VERSION); > > > > head = (struct ceph_mds_request_head_old *)&new_head->oldest_client_tid; > > > > p = msg->front.iov_base + sizeof(*new_head); > > > > @@ -2761,7 +2797,7 @@ static struct ceph_msg *create_request_message(struct ceph_mds_session *session, > > > > > > > > head->num_releases = cpu_to_le16(releases); > > > > > > > > - encode_timestamp_and_gids(&p, req); > > > > + encode_mclientrequest_tail(&p, req); > > > > > > > > if (WARN_ONCE(p > end, "p=%p end=%p len=%d\n", p, end, len)) { > > > > ceph_msg_put(msg); > > > > @@ -2870,7 +2906,7 @@ static int __prepare_send_request(struct ceph_mds_session *session, > > > > rhead->num_releases = 0; > > > > > > > > p = msg->front.iov_base + req->r_request_release_offset; > > > > - encode_timestamp_and_gids(&p, req); > > > > + encode_mclientrequest_tail(&p, req); > > > > > > > > msg->front.iov_len = p - msg->front.iov_base; > > > > msg->hdr.front_len = cpu_to_le32(msg->front.iov_len); > > > > diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h > > > > index 98a8710807d1..e7d2c8a1b9c1 100644 > > > > --- a/fs/ceph/mds_client.h > > > > +++ b/fs/ceph/mds_client.h > > > > @@ -278,6 +278,9 @@ struct ceph_mds_request { > > > > struct mutex r_fill_mutex; > > > > > > > > union ceph_mds_request_args r_args; > > > > + > > > > + struct ceph_fscrypt_auth *r_fscrypt_auth; > > > > + > > > > int r_fmode; /* file mode, if expecting cap */ > > > > const struct cred *r_cred; > > > > int r_request_release_offset; > > > > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > > > > index 6bb6f9f9d79a..bc74c0b19c4f 100644 > > > > --- a/fs/ceph/super.h > > > > +++ b/fs/ceph/super.h > > > > @@ -1040,7 +1040,12 @@ static inline int ceph_do_getattr(struct inode *inode, int mask, bool force) > > > > } > > > > extern int ceph_permission(struct user_namespace *mnt_userns, > > > > struct inode *inode, int mask); > > > > -extern int __ceph_setattr(struct inode *inode, struct iattr *attr); > > > > + > > > > +struct ceph_iattr { > > > > + struct ceph_fscrypt_auth *fscrypt_auth; > > > > +}; > > > > + > > > > +extern int __ceph_setattr(struct inode *inode, struct iattr *attr, struct ceph_iattr *cia); > > > > extern int ceph_setattr(struct user_namespace *mnt_userns, > > > > struct dentry *dentry, struct iattr *attr); > > > > extern int ceph_getattr(struct user_namespace *mnt_userns, > > > > diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h > > > > index bc2699feddbe..a7d801a6ac88 100644 > > > > --- a/include/linux/ceph/ceph_fs.h > > > > +++ b/include/linux/ceph/ceph_fs.h > > > > @@ -356,14 +356,19 @@ enum { > > > > > > > > extern const char *ceph_mds_op_name(int op); > > > > > > > > - > > > > -#define CEPH_SETATTR_MODE 1 > > > > -#define CEPH_SETATTR_UID 2 > > > > -#define CEPH_SETATTR_GID 4 > > > > -#define CEPH_SETATTR_MTIME 8 > > > > -#define CEPH_SETATTR_ATIME 16 > > > > -#define CEPH_SETATTR_SIZE 32 > > > > -#define CEPH_SETATTR_CTIME 64 > > > > +#define CEPH_SETATTR_MODE (1 << 0) > > > > +#define CEPH_SETATTR_UID (1 << 1) > > > > +#define CEPH_SETATTR_GID (1 << 2) > > > > +#define CEPH_SETATTR_MTIME (1 << 3) > > > > +#define CEPH_SETATTR_ATIME (1 << 4) > > > > +#define CEPH_SETATTR_SIZE (1 << 5) > > > > +#define CEPH_SETATTR_CTIME (1 << 6) > > > > +#define CEPH_SETATTR_MTIME_NOW (1 << 7) > > > > +#define CEPH_SETATTR_ATIME_NOW (1 << 8) > > > > +#define CEPH_SETATTR_BTIME (1 << 9) > > > > +#define CEPH_SETATTR_KILL_SGUID (1 << 10) > > > > +#define CEPH_SETATTR_FSCRYPT_AUTH (1 << 11) > > > > +#define CEPH_SETATTR_FSCRYPT_FILE (1 << 12) > > > > > > > > /* > > > > * Ceph setxattr request flags. > -- Jeff Layton