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Message-ID: <3e0961dec832a54bc6a59776831e5467ed231333.camel@kernel.org>
Subject: Re: [fscrypt][RFC PATCH v2] ceph: don't allow changing layout on
 encrypted files/directories
From:   Jeff Layton <jlayton@kernel.org>
To:     Luis Henriques <lhenriques@suse.de>
Cc:     ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Wed, 18 Aug 2021 08:20:55 -0400
In-Reply-To: <20210817140439.1442-1-lhenriques@suse.de>
References: <20210817140439.1442-1-lhenriques@suse.de>
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On Tue, 2021-08-17 at 15:04 +0100, Luis Henriques wrote:
> Encryption is currently only supported on files/directories with layouts
> where stripe_count=1.  Forbid changing layouts when encryption is involved.
> 
> Signed-off-by: Luis Henriques <lhenriques@suse.de>
> ---
> Changes since v1:
> - dropped changes to ceph_sync_setxattr(), MDS shall be responsible for
>   preventing layout changes on encrypted dirs/files
> 
>  fs/ceph/ioctl.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/fs/ceph/ioctl.c b/fs/ceph/ioctl.c
> index 477ecc667aee..480d18bb2ff0 100644
> --- a/fs/ceph/ioctl.c
> +++ b/fs/ceph/ioctl.c
> @@ -294,6 +294,10 @@ static long ceph_set_encryption_policy(struct file *file, unsigned long arg)
>  	struct inode *inode = file_inode(file);
>  	struct ceph_inode_info *ci = ceph_inode(inode);
>  
> +	/* encrypted directories can't have striped layout */
> +	if (ci->i_layout.stripe_count > 1)
> +		return -EINVAL;
> +
>  	ret = vet_mds_for_fscrypt(file);
>  	if (ret)
>  		return ret;

Thanks Luis. I've gone ahead and merged this into my fscrypt pile.
-- 
Jeff Layton <jlayton@kernel.org>