pull up r24056 from trunk

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 r24056 | tlyu | 2010-05-19 14:09:37 -0400 (Wed, 19 May 2010) | 8 lines

 ticket: 6725
 subject: CVE-2010-1321 GSS-API lib null pointer deref (MITKRB5-SA-2010-005)
 tags: pullup
 target_version: 1.8.2

 Make krb5_gss_accept_sec_context() check for a null authenticator
 checksum pointer before attempting to dereference it.

https://github.com/krb5/krb5/commit/f13587dd881b1df5cd613a0957116023c159f77e
Commit By: tlyu
Revision: 24063
Changed Files:
U   branches/krb5-1-8/src/lib/gssapi/krb5/accept_sec_context.c