From: Stefan Metzmacher <metze@samba.org>
Date: Fri, 7 Nov 2014 23:57:40 +0000 (-0800)
Subject: s3:smbd: fix file corruption using "write cache size != 0"
X-Git-Tag: samba-4.0.23~39
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7e486b942c7e5cd923bb9ced6b7bc9649bc7100e;p=thirdparty%2Fsamba.git

s3:smbd: fix file corruption using "write cache size != 0"

A client can:
- open a handle (h1)
- write some data to h1.
- open a 2nd handle h2 (downgrades both handles to level II)
- try to read the data on h2 (this gets old data)

Bug: https://bugzilla.samba.org/show_bug.cgi?id=10921

Signed-off-by: Stefan Metzmacher <metze@samba.org>

Autobuild-User(v4-0-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-0-test): Sun Nov  9 22:51:19 CET 2014 on sn-devel-104
---

diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c
index 95d88ef3813..045fd46967d 100644
--- a/source3/smbd/oplock.c
+++ b/source3/smbd/oplock.c
@@ -151,6 +151,9 @@ static void downgrade_file_oplock(files_struct *fsp)
 	sconn->oplocks.level_II_open++;
 	fsp->sent_oplock_break = NO_BREAK_SENT;
 
+	flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
+	delete_write_cache(fsp);
+
 	TALLOC_FREE(fsp->oplock_timeout);
 }