linux-kernel - [RFC PATCH 2/2] ceph: switch atomic open to use new fscrypt helper

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230309121910.18939-3-lhenriques@suse.de>
Date:   Thu,  9 Mar 2023 12:19:10 +0000
From:   Luís Henriques <lhenriques@...e.de>
To:     Eric Biggers <ebiggers@...nel.org>, Xiubo Li <xiubli@...hat.com>,
        Jeff Layton <jlayton@...nel.org>
Cc:     "Theodore Y. Ts'o" <tytso@....edu>,
        Jaegeuk Kim <jaegeuk@...nel.org>,
        Ilya Dryomov <idryomov@...il.com>,
        linux-fscrypt@...r.kernel.org, ceph-devel@...r.kernel.org,
        linux-kernel@...r.kernel.org,
        Luís Henriques <lhenriques@...e.de>
Subject: [RFC PATCH 2/2] ceph: switch atomic open to use new fscrypt helper

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@...e.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) {