Pull up r25723 from trunk

Pull up r25723 from trunk

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 r25723 | ghudson | 2012-03-01 15:49:17 -0500 (Thu, 01 Mar 2012) | 16 lines

 ticket: 7096
 subject: Fix KDB iteration when callback does write calls
 target_version: 1.10.1
 tags: pullup

 kdb_db2's ctx_iterate makes an convenience alias to dbc->db in order
 to call more invoke call the DB's seq method.  This alias may become
 invalidated if the callback writes to the DB, since ctx_lock() may
 re-open the DB in order to acquire a write lock.  Fix the bug by
 getting rid of the convenience alias.

 Most KDB iteration operations in the code base do not write to the DB,
 but kdb5_util update_princ_encryption does.

 Bug discovered and diagnosed by will.fiveash@oracle.com.

ticket: 7096
version_fixed: 1.10.1
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-10@25740 dc483132-0cff-0310-8789-dd5450dbe970