Re: [PATCH 2/2] ceph: switch atomic open to use new fscrypt helper

From: Eric Biggers <ebiggers@kernel.org>
To: "Luís Henriques" <lhenriques@suse.de>
Cc: Xiubo Li <xiubli@redhat.com>, Jeff Layton <jlayton@kernel.org>,
	"Theodore Y. Ts'o" <tytso@mit.edu>,
	Jaegeuk Kim <jaegeuk@kernel.org>,
	Ilya Dryomov <idryomov@gmail.com>,
	linux-fscrypt@vger.kernel.org, ceph-devel@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] ceph: switch atomic open to use new fscrypt helper
Date: Mon, 13 Mar 2023 11:11:09 -0700	[thread overview]
Message-ID: <ZA9nPXNpBX0U5joC@sol.localdomain> (raw)
In-Reply-To: <20230313123310.13040-3-lhenriques@suse.de>

On Mon, Mar 13, 2023 at 12:33:10PM +0000, Luís Henriques wrote:
> Switch ceph atomic open to use fscrypt_prepare_atomic_open().  This fixes
> a bug where a dentry is incorrectly set with DCACHE_NOKEY_NAME when 'dir'
> has been evicted but the key is still available (for example, where there's
> a drop_caches).
> 
> Signed-off-by: Luís Henriques <lhenriques@suse.de>
> ---
>  fs/ceph/file.c | 8 +++-----
>  1 file changed, 3 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/ceph/file.c b/fs/ceph/file.c
> index dee3b445f415..5ad57cc4c13b 100644
> --- a/fs/ceph/file.c
> +++ b/fs/ceph/file.c
> @@ -795,11 +795,9 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
>  	ihold(dir);
>  	if (IS_ENCRYPTED(dir)) {
>  		set_bit(CEPH_MDS_R_FSCRYPT_FILE, &req->r_req_flags);
> -		if (!fscrypt_has_encryption_key(dir)) {
> -			spin_lock(&dentry->d_lock);
> -			dentry->d_flags |= DCACHE_NOKEY_NAME;
> -			spin_unlock(&dentry->d_lock);
> -		}
> +		err = fscrypt_prepare_atomic_open(dir, dentry);
> +		if (err)
> +			goto out_req;

Note that this patch does not apply to upstream or even to linux-next.

I'd be glad to take patch 1 through the fscrypt tree for 6.4.  But I'm wondering
what the current plans are for getting ceph's fscrypt support upstream?

- Eric