krb5 commit [krb5-1.13]: Avoid byte-swap cache corruption in libdb2

[Tom Yu]

https://github.com/krb5/krb5/commit/bf8ccad8f2fd6d1ea90d1bd16de117f800ce3730
commit bf8ccad8f2fd6d1ea90d1bd16de117f800ce3730
Author: Tom Yu <tlyu at mit.edu>
Date:   Thu Aug 25 18:02:56 2016 -0400

    Avoid byte-swap cache corruption in libdb2
    
    Apply a patch from NetBSD to restore the cached copy of a page to the
    machine byte order after a write operation swapped it to the file byte
    order.  As a regression test, modify test13 to sync the database file
    after each put to exercise this bug.
    
    (cherry picked from commit 56d02135d4c77b6aa0cb7136477d426248c60a6f)
    
    ticket: 8483
    version_fixed: 1.13.7

 src/plugins/kdb/db2/libdb2/mpool/mpool.c |    8 ++++++++
 src/plugins/kdb/db2/libdb2/test/run.test |    1 +
 2 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/src/plugins/kdb/db2/libdb2/mpool/mpool.c b/src/plugins/kdb/db2/libdb2/mpool/mpool.c
index 7941a9f..81ecccc 100644
--- a/src/plugins/kdb/db2/libdb2/mpool/mpool.c
+++ b/src/plugins/kdb/db2/libdb2/mpool/mpool.c
@@ -431,6 +431,14 @@ mpool_write(mp, bp)
 	if (write(mp->fd, bp->page, mp->pagesize) != mp->pagesize)
 		return (RET_ERROR);
 
+	/*
+	 * Re-run through the input filter since this page may soon be
+	 * accessed via the cache, and whatever the user's output filter
+	 * did may screw things up if we don't let the input filter
+	 * restore the in-core copy.
+	 */
+	if (mp->pgin)
+		(mp->pgin)(mp->pgcookie, bp->pgno, bp->page);
 	bp->flags &= ~MPOOL_DIRTY;
 	return (RET_SUCCESS);
 }
diff --git a/src/plugins/kdb/db2/libdb2/test/run.test b/src/plugins/kdb/db2/libdb2/test/run.test
index 729ca1f..b907105 100644
--- a/src/plugins/kdb/db2/libdb2/test/run.test
+++ b/src/plugins/kdb/db2/libdb2/test/run.test
@@ -614,6 +614,7 @@ test13()
 				echo p
 				echo k$i
 				echo d$i
+				echo S
 				echo g
 				echo k$i
 			done > $TMP2