From:   =?UTF-8?q?Lu=C3=ADs=20Henriques?= <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,
        =?UTF-8?q?Lu=C3=ADs=20Henriques?= <lhenriques@suse.de>
Subject: [RFC PATCH 2/2] ceph: switch atomic open to use new fscrypt helper
Date:   Thu,  9 Mar 2023 12:19:10 +0000
Message-Id: <20230309121910.18939-3-lhenriques@suse.de>
In-Reply-To: <20230309121910.18939-1-lhenriques@suse.de>
References: <20230309121910.18939-1-lhenriques@suse.de>
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Switch ceph atomic open to use __fscrypt_prepare_atomic_open().  This fixes
a bug where a dentry is incorrectly set with DCACHE_NOKEY_NAME.  This
happens 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..bdd7a7de7d9e 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;
 	}
 
 	if (flags & O_CREAT) {