Commit 0d91f0ad authored by Jeff Layton's avatar Jeff Layton Committed by Ilya Dryomov
Browse files

ceph: handle fscrypt fields in cap messages from MDS 



Handle the new fscrypt_file and fscrypt_auth fields in cap messages. Use
them to populate new fields in cap_extra_info and update the inode with
those values.

Signed-off-by: default avatarJeff Layton <jlayton@kernel.org>
Reviewed-by: default avatarXiubo Li <xiubli@redhat.com>
Reviewed-and-tested-by: default avatarLuís Henriques <lhenriques@suse.de>
Reviewed-by: default avatarMilind Changire <mchangir@redhat.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 16be62fc

fs/ceph/caps.c

+83 −2
Original line number Diff line number Diff line
@@ -3383,6 +3383,9 @@ struct cap_extra_info { 
	/* currently issued */

	int issued;

	struct timespec64 btime;

	u8 *fscrypt_auth;

	u32 fscrypt_auth_len;

	u64 fscrypt_file_size;

};



/*
@@ -3415,6 +3418,14 @@ static void handle_cap_grant(struct inode *inode, 
	bool deleted_inode = false;

	bool fill_inline = false;



	/*

	 * If there is at least one crypto block then we'll trust

	 * fscrypt_file_size. If the real length of the file is 0, then

	 * ignore it (it has probably been truncated down to 0 by the MDS).

	 */

	if (IS_ENCRYPTED(inode) && size)

		size = extra_info->fscrypt_file_size;



	dout("handle_cap_grant inode %p cap %p mds%d seq %d %s\n",

	     inode, cap, session->s_mds, seq, ceph_cap_string(newcaps));

	dout(" size %llu max_size %llu, i_size %llu\n", size, max_size,
@@ -3481,6 +3492,14 @@ static void handle_cap_grant(struct inode *inode, 
		dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,

		     from_kuid(&init_user_ns, inode->i_uid),

		     from_kgid(&init_user_ns, inode->i_gid));

#if IS_ENABLED(CONFIG_FS_ENCRYPTION)

		if (ci->fscrypt_auth_len != extra_info->fscrypt_auth_len ||

		    memcmp(ci->fscrypt_auth, extra_info->fscrypt_auth,

			   ci->fscrypt_auth_len))

			pr_warn_ratelimited("%s: cap grant attempt to change fscrypt_auth on non-I_NEW inode (old len %d new len %d)\n",

				__func__, ci->fscrypt_auth_len,

				extra_info->fscrypt_auth_len);

#endif

	}



	if ((newcaps & CEPH_CAP_LINK_SHARED) &&
@@ -3897,7 +3916,8 @@ static void handle_cap_flushsnap_ack(struct inode *inode, u64 flush_tid, 
 */

static bool handle_cap_trunc(struct inode *inode,

			     struct ceph_mds_caps *trunc,

			     struct ceph_mds_session *session)

			     struct ceph_mds_session *session,

			     struct cap_extra_info *extra_info)

{

	struct ceph_inode_info *ci = ceph_inode(inode);

	int mds = session->s_mds;
@@ -3914,6 +3934,14 @@ static bool handle_cap_trunc(struct inode *inode, 


	issued |= implemented | dirty;



	/*

	 * If there is at least one crypto block then we'll trust

	 * fscrypt_file_size. If the real length of the file is 0, then

	 * ignore it (it has probably been truncated down to 0 by the MDS).

	 */

	if (IS_ENCRYPTED(inode) && size)

		size = extra_info->fscrypt_file_size;



	dout("handle_cap_trunc inode %p mds%d seq %d to %lld seq %d\n",

	     inode, mds, seq, truncate_size, truncate_seq);

	queue_trunc = ceph_fill_file_size(inode, issued,
@@ -4135,6 +4163,52 @@ static void handle_cap_import(struct ceph_mds_client *mdsc, 
	*target_cap = cap;

}



#ifdef CONFIG_FS_ENCRYPTION

static int parse_fscrypt_fields(void **p, void *end,

				struct cap_extra_info *extra)

{

	u32 len;



	ceph_decode_32_safe(p, end, extra->fscrypt_auth_len, bad);

	if (extra->fscrypt_auth_len) {

		ceph_decode_need(p, end, extra->fscrypt_auth_len, bad);

		extra->fscrypt_auth = kmalloc(extra->fscrypt_auth_len,

					      GFP_KERNEL);

		if (!extra->fscrypt_auth)

			return -ENOMEM;

		ceph_decode_copy_safe(p, end, extra->fscrypt_auth,

					extra->fscrypt_auth_len, bad);

	}



	ceph_decode_32_safe(p, end, len, bad);

	if (len >= sizeof(u64)) {

		ceph_decode_64_safe(p, end, extra->fscrypt_file_size, bad);

		len -= sizeof(u64);

	}

	ceph_decode_skip_n(p, end, len, bad);

	return 0;

bad:

	return -EIO;

}

#else

static int parse_fscrypt_fields(void **p, void *end,

				struct cap_extra_info *extra)

{

	u32 len;



	/* Don't care about these fields unless we're encryption-capable */

	ceph_decode_32_safe(p, end, len, bad);

	if (len)

		ceph_decode_skip_n(p, end, len, bad);

	ceph_decode_32_safe(p, end, len, bad);

	if (len)

		ceph_decode_skip_n(p, end, len, bad);

	return 0;

bad:

	return -EIO;

}

#endif



/*

 * Handle a caps message from the MDS.

 *
@@ -4255,6 +4329,11 @@ void ceph_handle_caps(struct ceph_mds_session *session, 
		ceph_decode_64_safe(&p, end, extra_info.nsubdirs, bad);

	}



	if (msg_version >= 12) {

		if (parse_fscrypt_fields(&p, end, &extra_info))

			goto bad;

	}



	/* lookup ino */

	inode = ceph_find_inode(mdsc->fsc->sb, vino);

	dout(" op %s ino %llx.%llx inode %p\n", ceph_cap_op_name(op), vino.ino,
@@ -4352,7 +4431,8 @@ void ceph_handle_caps(struct ceph_mds_session *session, 
		break;



	case CEPH_CAP_OP_TRUNC:

		queue_trunc = handle_cap_trunc(inode, h, session);

		queue_trunc = handle_cap_trunc(inode, h, session,

						&extra_info);

		spin_unlock(&ci->i_ceph_lock);

		if (queue_trunc)

			ceph_queue_vmtruncate(inode);
@@ -4375,6 +4455,7 @@ void ceph_handle_caps(struct ceph_mds_session *session, 
	if (close_sessions)

		ceph_mdsc_close_sessions(mdsc);



	kfree(extra_info.fscrypt_auth);

	return;



flush_cap_releases: