From: =?utf-8?q?Guido_G=C3=BCnther?= <agx@sigxcpu.org>
Date: Fri, 7 Jul 2017 09:10:37 +0200
Subject: credentials_expiring_real: check if kcontext is valid

othewise we might crash when the credentials_expiring_once fires but
we're already shutting down.

LP: #1700468
---
 src/ka-kerberos.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/ka-kerberos.c b/src/ka-kerberos.c
index 14fb03e..59f6b8b 100644
--- a/src/ka-kerberos.c
+++ b/src/ka-kerberos.c
@@ -222,6 +222,9 @@ credentials_expiring_real (KaApplet *applet)
     krb5_timestamp now;
     gboolean retval = FALSE;
 
+    if (!kcontext_valid)
+        return retval;
+
     memset (&my_creds, 0, sizeof (my_creds));
     ka_applet_set_tgt_renewable (applet, FALSE);
     if (!ka_get_tgt_from_ccache (kcontext, &my_creds)) {
@@ -947,8 +950,8 @@ static gboolean
 ka_krb5_context_free ()
 {
     if (kcontext_valid) {
-        krb5_free_context (kcontext);
         kcontext_valid = FALSE;
+        krb5_free_context (kcontext);
     }
     return TRUE;
 }