Try to recover from closing a freed cursor

kriszyp · kriszyp · commit e764d2c76d0c · 2025-01-21T10:01:19.000-07:00
diff --git a/dependencies/lmdb/libraries/liblmdb/mdb.c b/dependencies/lmdb/libraries/liblmdb/mdb.c
@@ -10357,6 +10357,11 @@ void
 mdb_cursor_close(MDB_cursor *mc)
 {
 	if (mc) {
+		if (!mc->mc_txn || !mc->mc_txn->mt_env) {
+	        fprintf(stderr, "cursor_close: mc->mc_txn or mc->mc_txn->mt_env is NULL, ensure that cursors are closed before the transaction is closed\n");
+			free(mc);
+			return;
+        }
 		MDB_CURSOR_UNREF(mc, 0);
 	}
 	if (mc && !mc->mc_backup) {

Original file line number	Diff line number	Diff line change
`@@ -10357,6 +10357,11 @@ void`
`10357`	`10357`	`mdb_cursor_close(MDB_cursor *mc)`
`10358`	`10358`	`{`
`10359`	`10359`	`if (mc) {`
	`10360`	`+ if (!mc->mc_txn \|\| !mc->mc_txn->mt_env) {`
	`10361`	`+ fprintf(stderr, "cursor_close: mc->mc_txn or mc->mc_txn->mt_env is NULL, ensure that cursors are closed before the transaction is closed\n");`
	`10362`	`+ free(mc);`
	`10363`	`+ return;`
	`10364`	`+ }`
`10360`	`10365`	`MDB_CURSOR_UNREF(mc, 0);`
`10361`	`10366`	`}`
`10362`	`10367`	`if (mc && !mc->mc_backup) {`