[PATCH] ceph: make sure directories aren't complete after setting crypt context

From: "Luís Henriques" <lhenriques@suse.de>
To: Xiubo Li <xiubli@redhat.com>, Ilya Dryomov <idryomov@gmail.com>,
	Jeff Layton <jlayton@kernel.org>
Cc: ceph-devel@vger.kernel.org, linux-kernel@vger.kernel.org,
	"Luís Henriques" <lhenriques@suse.de>
Subject: [PATCH] ceph: make sure directories aren't complete after setting crypt context
Date: Wed, 16 Nov 2022 15:37:03 +0000	[thread overview]
Message-ID: <20221116153703.27292-1-lhenriques@suse.de> (raw)

When setting a directory's crypt context, __ceph_dir_clear_complete() needs
to be used otherwise, if it was complete before, any old dentry that's still
around will be valid.

Signed-off-by: Luís Henriques <lhenriques@suse.de>
---
Hi!

Here's a simple way to trigger the bug this patch is fixing:

# cd /cephfs
# ls mydir
nKRhofOAVNsAwVLvDw7a0c9ypsjbZfK3n0Npnmni6j0
# ls mydir/nKRhofOAVNsAwVLvDw7a0c9ypsjbZfK3n0Npnmni6j0/
Cyuer5xT+kBlEPgtwAqSj0WK2taEljP5vHZ,D8VXCJ8  u+46b2XVCt7Obpz0gznZyNLRj79Q2l4KmkwbKOzdQKw
# fscrypt unlock mydir
# touch /mnt/test/mydir/mysubdir/file
touch: cannot touch '/mnt/test/mydir/mysubdir/file': No such file or directory

 fs/ceph/crypto.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/fs/ceph/crypto.c b/fs/ceph/crypto.c
index 35a2ccfe6899..dc1557967032 100644
--- a/fs/ceph/crypto.c
+++ b/fs/ceph/crypto.c
@@ -87,6 +87,10 @@ static int ceph_crypt_get_context(struct inode *inode, void *ctx, size_t len)
 		return -ERANGE;
 
 	memcpy(ctx, cfa->cfa_blob, ctxlen);
+
+	/* Directory isn't complete anymore */
+	if (S_ISDIR(inode->i_mode) && __ceph_dir_is_complete(ci))
+		__ceph_dir_clear_complete(ci);
 	return ctxlen;
 }
 
