From: Howard Chu <hyc@openldap.org>
Date: Thu, 6 Dec 2007 05:48:02 +0000 (+0000)
Subject: ITS#5262 must protect dn2id between the time it's read from the DB
X-Git-Tag: OPENLDAP_REL_ENG_2_4_9~20^2~350
X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=cb0e31fc65e155d3627e70ee1f3489e7951f3862;p=openldap

ITS#5262 must protect dn2id between the time it's read from the DB
and it's inserted into EntryInfo cache.
---

diff --git a/servers/slapd/back-bdb/back-bdb.h b/servers/slapd/back-bdb/back-bdb.h
index 6e49d132a2..c83ddf0764 100644
--- a/servers/slapd/back-bdb/back-bdb.h
+++ b/servers/slapd/back-bdb/back-bdb.h
@@ -70,13 +70,15 @@ typedef struct __db_locker * BDB_LOCKER;
 extern int __lock_getlocker(DB_LOCKTAB *lt, u_int32_t locker, int create, DB_LOCKER **ret);
 
 #define CURSOR_SETLOCKER(cursor, id)	cursor->locker = id
-#define	CURSOR_GETLOCKER(cursor)	cursor->locker
+#define CURSOR_GETLOCKER(cursor)	cursor->locker
+#define BDB_LOCKID(locker)	locker->id
 #else
 
 typedef u_int32_t BDB_LOCKER;
 
 #define CURSOR_SETLOCKER(cursor, id)	cursor->locker = id
 #define CURSOR_GETLOCKER(cursor)	cursor->locker
+#define BDB_LOCKID(locker)	locker
 
 #endif
 
diff --git a/servers/slapd/back-bdb/cache.c b/servers/slapd/back-bdb/cache.c
index 93be806635..ffe8580cfc 100644
--- a/servers/slapd/back-bdb/cache.c
+++ b/servers/slapd/back-bdb/cache.c
@@ -155,12 +155,6 @@ bdb_cache_lru_link( struct bdb_info *bdb, EntryInfo *ei )
  * alternatives though.
  */
 
-#if DB_VERSION_FULL >= 0x04060012
-#define BDB_LOCKID(locker)	locker->id
-#else
-#define BDB_LOCKID(locker)	locker
-#endif
-
 /* Atomically release and reacquire a lock */
 int
 bdb_cache_entry_db_relock(
@@ -426,6 +420,7 @@ bdb_cache_find_ndn(
 		ei.bei_parent = eip;
 		ei2 = (EntryInfo *)avl_find( eip->bei_kids, &ei, bdb_rdn_cmp );
 		if ( !ei2 ) {
+			DB_LOCK lock;
 			int len = ei.bei_nrdn.bv_len;
 				
 			if ( BER_BVISEMPTY( ndn )) {
@@ -442,9 +437,11 @@ bdb_cache_find_ndn(
 				ei.bei_nrdn.bv_val );
 #endif
 
-			rc = bdb_dn2id( op, locker, &ei.bei_nrdn, &ei );
+			lock.mode = DB_LOCK_NG;
+			rc = bdb_dn2id( op, &ei.bei_nrdn, &ei, locker, &lock );
 			if (rc) {
 				bdb_cache_entryinfo_lock( eip );
+				bdb_cache_entry_db_unlock( bdb, &lock );
 				*res = eip;
 				return rc;
 			}
@@ -461,6 +458,7 @@ bdb_cache_find_ndn(
 				ei.bei_nrdn.bv_val, ei.bei_id, 0 );
 			/* add_internal left eip and c_rwlock locked */
 			ldap_pvt_thread_rdwr_wunlock( &bdb->bi_cache.c_rwlock );
+			bdb_cache_entry_db_unlock( bdb, &lock );
 			if ( rc ) {
 				*res = eip;
 				return rc;
diff --git a/servers/slapd/back-bdb/dn2id.c b/servers/slapd/back-bdb/dn2id.c
index 0f6b1927bb..33234ceaa0 100644
--- a/servers/slapd/back-bdb/dn2id.c
+++ b/servers/slapd/back-bdb/dn2id.c
@@ -23,6 +23,29 @@
 #include "idl.h"
 #include "lutil.h"
 
+#define bdb_dn2id_lock					BDB_SYMBOL(dn2id_lock)
+
+static int
+bdb_dn2id_lock( struct bdb_info *bdb, struct berval *dn,
+	int rw, BDB_LOCKER locker, DB_LOCK *lock )
+{
+	int       rc;
+	DBT       lockobj;
+	int       db_rw;
+
+	if (rw)
+		db_rw = DB_LOCK_WRITE;
+	else
+		db_rw = DB_LOCK_READ;
+
+	lockobj.data = dn->bv_val;
+	lockobj.size = dn->bv_len;
+
+	rc = LOCK_GET(bdb->bi_dbenv, BDB_LOCKID(locker), DB_LOCK_NOWAIT,
+					&lockobj, db_rw, lock);
+	return rc;
+}
+
 #ifndef BDB_HIER
 int
 bdb_dn2id_add(
@@ -146,10 +169,11 @@ bdb_dn2id_delete(
 {
 	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
 	DB *db = bdb->bi_dn2id->bdi_db;
-	int		rc;
-	DBT		key;
 	char		*buf;
+	DBT		key;
+	DB_LOCK	lock;
 	struct berval	pdn, ptr;
+	int		rc;
 
 	Debug( LDAP_DEBUG_TRACE, "=> bdb_dn2id_delete( \"%s\", 0x%08lx )\n",
 		e->e_ndn, e->e_id, 0 );
@@ -165,6 +189,10 @@ bdb_dn2id_delete(
 	AC_MEMCPY( ptr.bv_val, e->e_nname.bv_val, e->e_nname.bv_len );
 	ptr.bv_val[ptr.bv_len] = '\0';
 
+	/* We hold this lock until the TXN completes */
+	rc = bdb_dn2id_lock( bdb, &e->e_nname, 1, TXN_ID( txn ), &lock );
+	if ( rc ) return rc;
+
 	/* delete it */
 	rc = db->del( db, txn, &key, 0 );
 	if( rc != 0 ) {
@@ -244,9 +272,10 @@ done:
 int
 bdb_dn2id(
 	Operation *op,
-	BDB_LOCKER locker,
 	struct berval	*dn,
-	EntryInfo *ei )
+	EntryInfo *ei,
+	BDB_LOCKER locker,
+	DB_LOCK *lock )
 {
 	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
 	DB *db = bdb->bi_dn2id->bdi_db;
@@ -268,6 +297,9 @@ bdb_dn2id(
 	data.ulen = sizeof(ID);
 	data.flags = DB_DBT_USERMEM;
 
+	rc = bdb_dn2id_lock( bdb, dn, 0, locker, lock );
+	if ( rc ) return rc;
+
 	rc = db->cursor( db, NULL, &cursor, bdb->bi_db_opflags );
 	if ( rc ) return rc;
 	if ( locker ) {
@@ -576,6 +608,7 @@ hdb_dn2id_delete(
 	int rc;
 	ID	nid;
 	unsigned char dlen[2];
+	DB_LOCK	lock;
 
 	DBTzero(&key);
 	key.size = sizeof(ID);
@@ -589,6 +622,10 @@ hdb_dn2id_delete(
 	data.dlen = data.size;
 	data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 
+	/* We hold this lock until the TXN completes */
+	rc = bdb_dn2id_lock( bdb, &e->e_nname, 1, TXN_ID( txn ), &lock );
+	if ( rc ) return rc;
+
 	key.data = &nid;
 	rc = db->cursor( db, txn, &cursor, bdb->bi_db_opflags );
 	if ( rc ) return rc;
@@ -646,9 +683,10 @@ hdb_dn2id_delete(
 int
 hdb_dn2id(
 	Operation	*op,
-	BDB_LOCKER locker,
 	struct berval	*in,
-	EntryInfo	*ei )
+	EntryInfo	*ei,
+	BDB_LOCKER locker,
+	DB_LOCK *lock )
 {
 	struct bdb_info *bdb = (struct bdb_info *) op->o_bd->be_private;
 	DB *db = bdb->bi_dn2id->bdi_db;
@@ -677,6 +715,9 @@ hdb_dn2id(
 	data.dlen = data.ulen;
 	data.flags = DB_DBT_USERMEM | DB_DBT_PARTIAL;
 
+	rc = bdb_dn2id_lock( bdb, in, 0, locker, lock );
+	if ( rc ) return rc;
+
 	rc = db->cursor( db, NULL, &cursor, bdb->bi_db_opflags );
 	if ( rc ) return rc;
 	if ( locker ) {
diff --git a/servers/slapd/back-bdb/proto-bdb.h b/servers/slapd/back-bdb/proto-bdb.h
index d0f01989ad..d1691b0808 100644
--- a/servers/slapd/back-bdb/proto-bdb.h
+++ b/servers/slapd/back-bdb/proto-bdb.h
@@ -97,9 +97,10 @@ int bdb_dn2entry LDAP_P(( Operation *op, DB_TXN *tid,
 
 int bdb_dn2id(
 	Operation *op,
-	BDB_LOCKER locker,
 	struct berval *dn,
-	EntryInfo *ei );
+	EntryInfo *ei,
+	BDB_LOCKER locker,
+	DB_LOCK *lock );
 
 int bdb_dn2id_add(
 	Operation *op,