Ticket History #7096: Fix KDB iteration when callback does write calls

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/4df31be8282f744201814493ebe0dbe92bcb8bcd
Commit By: ghudson
Revision: 25723
Changed Files:
U trunk/src/plugins/kdb/db2/kdb_db2.c

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.

https://github.com/krb5/krb5/commit/fd769cb984077b539dcdcb883bdc96dcbd08cb4a
Commit By: tlyu
Revision: 25740
Changed Files:
U branches/krb5-1-10/src/plugins/kdb/db2/kdb_db2.c