krb5 commit [krb5-1.13]: Add test for empty K/M key data handling

[Tom Yu]

https://github.com/krb5/krb5/commit/75d61d3875e61679610a02f2b1b4bbac9af234cf
commit 75d61d3875e61679610a02f2b1b4bbac9af234cf
Author: Matt Rogers <mrogers at redhat.com>
Date:   Fri Apr 22 12:53:41 2016 -0400

    Add test for empty K/M key data handling
    
    (back ported from commit f2286a6493c7aab267cf0d9cca680edaf2968707)
    
    ticket: 8395
    version_fixed: 1.13.6
    tags: -pullup
    status: resolved

 src/tests/t_mkey.py |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/src/tests/t_mkey.py b/src/tests/t_mkey.py
index 8a5b84e..0785139 100644
--- a/src/tests/t_mkey.py
+++ b/src/tests/t_mkey.py
@@ -327,4 +327,11 @@ check_mkvno(realm.user_princ, 1)
 realm.run([kdb5_util, 'use_mkey', '2', 'now-1day'])
 check_mkey_list((2, defetype, True, True), (1, des3, True, False))
 
+# Regression test for #8395.  Purge the master key and verify that a
+# master key fetch does not segfault.
+realm.run_kadminl('purgekeys -all K/M')
+out = realm.run([kadmin_local, '-q', 'getprinc %s' % realm.user_princ], expected_code=1)
+if 'Cannot find master key record in database' not in out:
+    fail('Unexpected output from failed master key fetch')
+
 success('Master key rollover tests')