pull up r25368 from trunk

pull up r25368 from trunk

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 r25368 | tlyu | 2011-10-18 14:51:35 -0400 (Tue, 18 Oct 2011) | 8 lines

 ticket: 6981
 subject: SA-2011-006 KDC denial of service [CVE-2011-1527 CVE-2011-1528 CVE-2011-1529]
 target_version: 1.10
 tags: pullup

 Fix null pointer dereference and assertion failure conditions that
 could cause a denial of service.

ticket: 6981
version_fixed: 1.10
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-10@25387 dc483132-0cff-0310-8789-dd5450dbe970