[RFC PATCH v3 15/16] ceph: add fscrypt support to ceph_fill_trace

Jeff Layton
2020-09-14T19:18:48Z

When we get a dentry in a trace, decrypt the name so we can properly
instantiate the dentry.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
fs/ceph/inode.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index c3a7a9f5603d..8e9fb1311bb8 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1331,8 +1331,10 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
if (dir && req->r_op == CEPH_MDS_OP_LOOKUPNAME &&
test_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags) &&
!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
+ bool is_nokey = false;
struct qstr dname;
struct dentry *dn, *parent;
+ struct fscrypt_str oname = FSTR_INIT(NULL, 0);

BUG_ON(!rinfo->head->is_target);
BUG_ON(req->r_dentry);
@@ -1340,8 +1342,21 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
parent = d_find_any_alias(dir);
BUG_ON(!parent);

- dname.name = rinfo->dname;
- dname.len = rinfo->dname_len;
+ err = ceph_fname_alloc_buffer(dir, &oname);
+ if (err < 0) {
+ dput(parent);
+ goto done;
+ }
+
+ err = ceph_fname_to_usr(dir, rinfo->dname, rinfo->dname_len, NULL,
+ &oname, &is_nokey);
+ if (err < 0) {
+ dput(parent);
+ ceph_fname_free_buffer(dir, &oname);
+ goto done;
+ }
+ dname.name = oname.name;
+ dname.len = oname.len;
dname.hash = full_name_hash(parent, dname.name, dname.len);
tvino.ino = le64_to_cpu(rinfo->targeti.in->ino);
tvino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
@@ -1356,9 +1371,15 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
dname.len, dname.name, dn);
if (!dn) {
dput(parent);
+ ceph_fname_free_buffer(dir, &oname);
err = -ENOMEM;
goto done;
}
+ if (is_nokey) {
+ spin_lock(&dn->d_lock);
+ dn->d_flags |= DCACHE_ENCRYPTED_NAME;
+ spin_unlock(&dn->d_lock);
+ }
err = 0;
} else if (d_really_is_positive(dn) &&
(ceph_ino(d_inode(dn)) != tvino.ino ||
@@ -1370,6 +1391,7 @@ int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
dput(dn);
goto retry_lookup;
}
+ ceph_fname_free_buffer(dir, &oname);

req->r_dentry = dn;
dput(parent);
--
2.26.2