[gnome-online-accounts/gnome-3-22] kerberos: Don't leak the return_key in sign_in_identity_sync

[Debarshi Ray <debarshir src gnome org>]

commit b219e25ab1ab206add5e551912b00f57759d0609
Author: Debarshi Ray <debarshir gnome org>
Date:   Thu Jan 5 18:25:33 2017 +0100

    kerberos: Don't leak the return_key in sign_in_identity_sync
    
    https://bugzilla.gnome.org/show_bug.cgi?id=765121

 src/goabackend/goakerberosprovider.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/src/goabackend/goakerberosprovider.c b/src/goabackend/goakerberosprovider.c
index 9324f71..4c9ba70 100644
--- a/src/goabackend/goakerberosprovider.c
+++ b/src/goabackend/goakerberosprovider.c
@@ -1564,7 +1564,7 @@ sign_in_identity_sync (GoaKerberosProvider  *self,
 {
   GcrSecretExchange  *secret_exchange;
   char               *secret_key;
-  char               *return_key;
+  char               *return_key = NULL;
   char               *concealed_secret;
   char               *identity_object_path = NULL;
   gboolean            keys_exchanged;
@@ -1618,6 +1618,7 @@ sign_in_identity_sync (GoaKerberosProvider  *self,
   g_mutex_unlock (&identity_manager_mutex);
 
  out:
+  g_free (return_key);
   g_object_unref (secret_exchange);
   return identity_object_path;
 }