libceph: introduce ceph_x_authorizer_cleanup()

Commit ae385eaf24dc ("libceph: store session key in cephx authorizer")
introduced ceph_x_authorizer::session_key, but didn't update all the
exit/error paths.  Introduce ceph_x_authorizer_cleanup() to encapsulate
ceph_x_authorizer cleanup and switch to it.  This fixes ceph_x_destroy(),
which currently always leaks key and ceph_x_build_authorizer() error
paths.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>

2 files changed, 20 insertions, 12 deletions

diff --git a/net/ceph/auth_x.c b/net/ceph/auth_x.c
index ba6eb17226da..65054fd31b97 100644
--- a/net/ceph/auth_x.c
+++ b/net/ceph/auth_x.c
@@ -279,6 +279,15 @@ bad:
         return -EINVAL;
 }
 
+static void ceph_x_authorizer_cleanup(struct ceph_x_authorizer *au)
+{
+        ceph_crypto_key_destroy(&au->session_key);
+        if (au->buf) {
+                ceph_buffer_put(au->buf);
+                au->buf = NULL;
+        }
+}
+
 static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
                                    struct ceph_x_ticket_handler *th,
                                    struct ceph_x_authorizer *au)
@@ -297,7 +306,7 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
         ceph_crypto_key_destroy(&au->session_key);
         ret = ceph_crypto_key_clone(&au->session_key, &th->session_key);
         if (ret)
-                return ret;
+                goto out_au;
 
         maxlen = sizeof(*msg_a) + sizeof(msg_b) +
                 ceph_x_encrypt_buflen(ticket_blob_len);
@@ -309,8 +318,8 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
         if (!au->buf) {
                 au->buf = ceph_buffer_new(maxlen, GFP_NOFS);
                 if (!au->buf) {
-                        ceph_crypto_key_destroy(&au->session_key);
-                        return -ENOMEM;
+                        ret = -ENOMEM;
+                        goto out_au;
                 }
         }
         au->service = th->service;
@@ -340,7 +349,7 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
         ret = ceph_x_encrypt(&au->session_key, &msg_b, sizeof(msg_b),
                              p, end - p);
         if (ret < 0)
-                goto out_buf;
+                goto out_au;
         p += ret;
         au->buf->vec.iov_len = p - au->buf->vec.iov_base;
         dout(" built authorizer nonce %llx len %d\n", au->nonce,
@@ -348,9 +357,8 @@ static int ceph_x_build_authorizer(struct ceph_auth_client *ac,
         BUG_ON(au->buf->vec.iov_len > maxlen);
         return 0;
 
-out_buf:
-        ceph_buffer_put(au->buf);
-        au->buf = NULL;
+out_au:
+        ceph_x_authorizer_cleanup(au);
         return ret;
 }
 
@@ -624,8 +632,7 @@ static void ceph_x_destroy_authorizer(struct ceph_auth_client *ac,
 {
         struct ceph_x_authorizer *au = (void *)a;
 
-        ceph_crypto_key_destroy(&au->session_key);
-        ceph_buffer_put(au->buf);
+        ceph_x_authorizer_cleanup(au);
         kfree(au);
 }
 
@@ -653,8 +660,7 @@ static void ceph_x_destroy(struct ceph_auth_client *ac)
                 remove_ticket_handler(ac, th);
         }
 
-        if (xi->auth_authorizer.buf)
-                ceph_buffer_put(xi->auth_authorizer.buf);
+        ceph_x_authorizer_cleanup(&xi->auth_authorizer);
 
         kfree(ac->private);
         ac->private = NULL;
diff --git a/net/ceph/crypto.h b/net/ceph/crypto.h
index d1498224c49d..2e9cab09f37b 100644
--- a/net/ceph/crypto.h
+++ b/net/ceph/crypto.h
@@ -16,8 +16,10 @@ struct ceph_crypto_key {
 
 static inline void ceph_crypto_key_destroy(struct ceph_crypto_key *key)
 {
-        if (key)
+        if (key) {
                 kfree(key->key);
+                key->key = NULL;
+        }
 }
 
 int ceph_crypto_key_clone(struct ceph_crypto_key *dst,