From: Ralph Boehme <slow@samba.org>
Date: Fri, 26 May 2017 09:57:08 +0000 (+0200)
Subject: s3/smbd: fix exclusive lease optimisation
X-Git-Tag: ldb-1.1.30~63
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=19b938e1fa9822ac417a3b3a34519087470d7a18;p=thirdparty%2Fsamba.git

s3/smbd: fix exclusive lease optimisation

We need to expect any amount of "stat" opens on the file without
triggering an assert.

This is the correct fix for bug #11844. I guess we haven't seens this
very often before bug #12766 got fixed, because most clients were using
LEASES instead of OPLOCKS.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=12798

See also:
BUG: https://bugzilla.samba.org/show_bug.cgi?id=11844
BUG: https://bugzilla.samba.org/show_bug.cgi?id=12766

Pair-Programmed-With: Stefan Metzmacher <metze@samba.org>

Signed-off-by: Ralph Boehme <slow@samba.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>
---

diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c
index aa060ad3747..1b2a87b8d8a 100644
--- a/source3/smbd/oplock.c
+++ b/source3/smbd/oplock.c
@@ -26,6 +26,7 @@
 #include "smbd/globals.h"
 #include "messages.h"
 #include "../librpc/gen_ndr/open_files.h"
+#include "../librpc/gen_ndr/ndr_open_files.h"
 
 /*
  * helper function used by the kernel oplock backends to post the break message
@@ -167,17 +168,38 @@ bool update_num_read_oplocks(files_struct *fsp, struct share_mode_lock *lck)
 	uint32_t i;
 
 	if (fsp_lease_type_is_exclusive(fsp)) {
+		const struct share_mode_entry *e = NULL;
+		uint32_t e_lease_type = 0;
+
 		/*
 		 * If we're fully exclusive, we don't need a brlock entry
 		 */
 		remove_stale_share_mode_entries(d);
 
-		for (i=0; i<d->num_share_modes; i++) {
-			struct share_mode_entry *e = &d->share_modes[i];
-			uint32_t e_lease_type = get_lease_type(d, e);
+		e = find_share_mode_entry(lck, fsp);
+		if (e != NULL) {
+			e_lease_type = get_lease_type(d, e);
+		}
+
+		if (!lease_type_is_exclusive(e_lease_type)) {
+			char *timestr = NULL;
 
-			SMB_ASSERT(lease_type_is_exclusive(e_lease_type));
+			timestr = timeval_string(talloc_tos(),
+						 &fsp->open_time,
+						 true);
+
+			NDR_PRINT_DEBUG(share_mode_data, d);
+			DBG_ERR("file [%s] file_id [%s] gen_id [%lu] "
+				"open_time[%s] lease_type [0x%x] "
+				"oplock_type [0x%x]\n",
+				fsp_str_dbg(fsp),
+				file_id_string_tos(&fsp->file_id),
+				fsp->fh->gen_id, timestr,
+				e_lease_type, fsp->oplock_type);
+
+			smb_panic("Found non-exclusive lease");
 		}
+
 		return true;
 	}