pull up r23533 from trunk

pull up r23533 from trunk

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 r23533 | tlyu | 2009-12-28 21:42:51 -0500 (Mon, 28 Dec 2009) | 10 lines

 ticket: 6608
 subject: MITKRB5-SA-2009-003 CVE-2009-3295 KDC null deref in referrals
 tags: pullup
 target_version: 1.7.1

 On certain error conditions, prep_reprocess_req() calls kdc_err() with
 a null pointer as the format string, causing a null dereference and
 denial of service.  Legitimate protocol requests can trigger this
 problem.

ticket: 6608
version_fixed: 1.7.1
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-7@23534 dc483132-0cff-0310-8789-dd5450dbe970