svn commit: r301792 - stable/10/crypto/heimdal/lib/krb5

[Garrett Cooper]

Author: ngie
Date: Fri Jun 10 14:48:10 2016
New Revision: 301792
URL: https://svnweb.freebsd.org/changeset/base/301792

Log:
  MFC r299495:
  r299495 (by cem):
  
  libkrb5: Fix potential double-free
  
  If krb5_make_principal fails, tmp_creds.server may remain a pointer to freed
  memory and then be double-freed.  After freeing it the first time, initialize
  it to NULL, which causes subsequent krb5_free_principal calls to do the right
  thing.
  
  CID:		1273430

Modified:
  stable/10/crypto/heimdal/lib/krb5/get_cred.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/crypto/heimdal/lib/krb5/get_cred.c
==============================================================================
--- stable/10/crypto/heimdal/lib/krb5/get_cred.c	Fri Jun 10 14:45:20 2016	(r301791)
+++ stable/10/crypto/heimdal/lib/krb5/get_cred.c	Fri Jun 10 14:48:10 2016	(r301792)
@@ -831,6 +831,7 @@ get_cred_kdc_capath_worker(krb5_context 
 	if(strcmp(tgt_inst, server_realm) == 0)
 	    break;
 	krb5_free_principal(context, tmp_creds.server);
+	tmp_creds.server = NULL;
 	ret = krb5_make_principal(context, &tmp_creds.server,
 				  tgt_inst, KRB5_TGS_NAME, server_realm, NULL);
 	if(ret) {