[PATCH] dbwrap_ctdb: Treat empty records as non-existing

[Volker Lendecke]

Hi!

Attached find a patch that is meant as a workaround for bug
10008 until the problem is really fixed.

It does fix a lot of nasty messages in my tests.

Please review&push.

Thanks,

Volker

-- 
SerNet GmbH, Bahnhofsallee 1b, 37081 Göttingen
phone: +49-551-370000-0, fax: +49-551-370000-9
AG Göttingen, HRB 2816, GF: Dr. Johannes Loxen
http://www.sernet.de, mailto:kontakt at sernet.de

*****************************************************************
visit us on it-sa:IT security exhibitions in Nürnberg, Germany
October 8th - 10th 2013, hall 12, booth 333
free tickets available via code 270691 on: www.it-sa.de/gutschein
******************************************************************
-------------- next part --------------
From 5c9c2c287d9a801599d7a7f834881a7e61e3558f Mon Sep 17 00:00:00 2001
From: Volker Lendecke <vl at samba.org>
Date: Wed, 28 Aug 2013 11:34:08 +0000
Subject: [PATCH] dbwrap_ctdb: Treat empty records as non-existing

This is a patch implementing the workaround Christian mentioned in
https://bugzilla.samba.org/show_bug.cgi?id=10008#c5

Bug: https://bugzilla.samba.org/show_bug.cgi?id=10008
Signed-off-by: Volker Lendecke <vl at samba.org>
---
 source3/lib/ctdbd_conn.c         |  8 ++++++++
 source3/lib/dbwrap/dbwrap_ctdb.c | 10 ++++++++++
 2 files changed, 18 insertions(+)

diff --git a/source3/lib/ctdbd_conn.c b/source3/lib/ctdbd_conn.c
index 4f5dce0..f960541 100644
--- a/source3/lib/ctdbd_conn.c
+++ b/source3/lib/ctdbd_conn.c
@@ -1474,6 +1474,14 @@ NTSTATUS ctdbd_parse(struct ctdbd_connection *conn, uint32_t db_id,
 		goto fail;
 	}
 
+	if (reply->datalen == 0) {
+		/*
+		 * Treat an empty record as non-existing
+		 */
+		status = NT_STATUS_NOT_FOUND;
+		goto fail;
+	}
+
 	parser(key, make_tdb_data(&reply->data[0], reply->datalen),
 	       private_data);
 
diff --git a/source3/lib/dbwrap/dbwrap_ctdb.c b/source3/lib/dbwrap/dbwrap_ctdb.c
index f90e7b8..5a473f9 100644
--- a/source3/lib/dbwrap/dbwrap_ctdb.c
+++ b/source3/lib/dbwrap/dbwrap_ctdb.c
@@ -103,6 +103,16 @@ static int db_ctdb_ltdb_parser(TDB_DATA key, TDB_DATA data,
 	if (data.dsize < sizeof(struct ctdb_ltdb_header)) {
 		return -1;
 	}
+	if (data.dsize == sizeof(struct ctdb_ltdb_header)) {
+		/*
+		 * Making this a separate case that needs fixing
+		 * separately. This is an empty record. ctdbd does not
+		 * distinguish between empty and deleted records. Samba right
+		 * now can live without empty records, so lets treat zero-size
+		 * (i.e. deleted) records as non-existing.
+		 */
+		return -1;
+	}
 	state->parser(
 		key, (struct ctdb_ltdb_header *)data.dptr,
 		make_tdb_data(data.dptr + sizeof(struct ctdb_ltdb_header),
-- 
1.8.1.2