Back port r25723

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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.

https://github.com/krb5/krb5/commit/a9bfc23583411331fd78401815ebd040f2b93409
Commit By: tlyu
Revision: 25747
Changed Files:
U   branches/krb5-1-9/src/plugins/kdb/db2/kdb_db2.c