[PATCH v3 3/3] ceph: switch ceph_open_atomic() to use the new fscrypt helper

From: "Luís Henriques" <lhenriques@suse.de>
To: Eric Biggers <ebiggers@kernel.org>, Xiubo Li <xiubli@redhat.com>,
	Jeff Layton <jlayton@kernel.org>
Cc: "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,
	"Luís Henriques" <lhenriques@suse.de>
Subject: [PATCH v3 3/3] ceph: switch ceph_open_atomic() to use the new fscrypt helper
Date: Thu, 16 Mar 2023 18:14:13 +0000	[thread overview]
Message-ID: <20230316181413.26916-4-lhenriques@suse.de> (raw)
In-Reply-To: <20230316181413.26916-1-lhenriques@suse.de>

Switch ceph_atomic_open() to use new fscrypt helper function
fscrypt_prepare_lookup_partial().  This fixes a bug in the atomic open
operation 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..2448d0f1a9ea 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_lookup_partial(dir, dentry);
+		if (err < 0)
+			goto out_req;
 	}
 
 	if (flags & O_CREAT) {
