From: Gary Lockyer <gary@catalyst.net.nz>
Date: Tue, 6 Mar 2018 23:05:34 +0000 (+1300)
Subject: ldb_mdb: Don't allow modify operations on a read only db
X-Git-Tag: ldb-1.4.0~107
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0d2d1e5bf07bb6c4f2ac741e0a0287a4eab523a7;p=thirdparty%2Fsamba.git

ldb_mdb: Don't allow modify operations on a read only db

Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>
---

diff --git a/lib/ldb/ldb_mdb/ldb_mdb.c b/lib/ldb/ldb_mdb/ldb_mdb.c
index e073e17da3c..20315dfa557 100644
--- a/lib/ldb/ldb_mdb/ldb_mdb.c
+++ b/lib/ldb/ldb_mdb/ldb_mdb.c
@@ -162,6 +162,10 @@ static int lmdb_store(struct ltdb_private *ltdb,
 	MDB_txn *txn = NULL;
 	MDB_dbi dbi = 0;
 
+	if (ltdb->read_only) {
+		return LDB_ERR_UNWILLING_TO_PERFORM;
+	}
+
 	txn = lmdb_trans_get_tx(lmdb_private_trans_head(lmdb));
 	if (txn == NULL) {
 		ldb_debug(lmdb->ldb, LDB_DEBUG_FATAL, "No transaction");
@@ -216,6 +220,10 @@ static int lmdb_delete(struct ltdb_private *ltdb, struct ldb_val key)
 	MDB_txn *txn = NULL;
 	MDB_dbi dbi = 0;
 
+	if (ltdb->read_only) {
+		return LDB_ERR_UNWILLING_TO_PERFORM;
+	}
+
 	txn = lmdb_trans_get_tx(lmdb_private_trans_head(lmdb));
 	if (txn == NULL) {
 		ldb_debug(lmdb->ldb, LDB_DEBUG_FATAL, "No transaction");
@@ -472,6 +480,11 @@ static int lmdb_transaction_start(struct ltdb_private *ltdb)
 	struct lmdb_trans *ltx_head;
 	MDB_txn *tx_parent;
 
+	/* Do not take out the transaction lock on a read-only DB */
+	if (ltdb->read_only) {
+		return LDB_ERR_UNWILLING_TO_PERFORM;
+	}
+
 	ltx = talloc_zero(lmdb, struct lmdb_trans);
 	if (ltx == NULL) {
 		return ldb_oom(lmdb->ldb);