diff --git a/src/generator.c b/src/generator.c
index 7a96e095..5acc3227 100644
--- a/src/generator.c
+++ b/src/generator.c
@@ -153,7 +153,8 @@ retry:
 		keep_sockalive(cs->fd);
 
 		/* Test we can connect, authorise and get a block template */
-		gbt = si->data;
+		gbt = ckzalloc(sizeof(gbtbase_t));
+		si->data = gbt;
 		if (!gen_gbtbase(cs, gbt)) {
 			LOGINFO("Failed to get test block template from %s:%s!",
 				cs->url, cs->port);
@@ -192,7 +193,6 @@ static void kill_server(server_instance_t *si)
 	dealloc(cs->port);
 	dealloc(cs->auth);
 	dealloc(si->data);
-	dealloc(si);
 }
 
 static int gen_loop(proc_instance_t *pi)
@@ -1299,15 +1299,11 @@ static int server_mode(ckpool_t *ckp, proc_instance_t *pi)
 
 	ckp->servers = ckalloc(sizeof(server_instance_t *) * ckp->btcds);
 	for (i = 0; i < ckp->btcds; i++) {
-		gbtbase_t *gbt;
-
 		ckp->servers[i] = ckzalloc(sizeof(server_instance_t));
 		si = ckp->servers[i];
 		si->url = ckp->btcdurl[i];
 		si->auth = ckp->btcdauth[i];
 		si->pass = ckp->btcdpass[i];
-		gbt = ckzalloc(sizeof(gbtbase_t));
-		si->data = gbt;
 	}
 
 	ret = gen_loop(pi);
@@ -1315,6 +1311,7 @@ static int server_mode(ckpool_t *ckp, proc_instance_t *pi)
 	for (i = 0; i < ckp->btcds; i++) {
 		si = ckp->servers[i];
 		kill_server(si);
+		dealloc(si);
 	}
 	dealloc(ckp->servers);
 	return ret;
diff --git a/src/stratifier.c b/src/stratifier.c
index 19074635..37ede260 100644
--- a/src/stratifier.c
+++ b/src/stratifier.c
@@ -331,7 +331,7 @@ static void generate_coinbase(ckpool_t *ckp, workbase_t *wb)
 	len += wb->enonce1varlen;
 	len += wb->enonce2varlen;
 
-	wb->coinb2bin = ckalloc(128);
+	wb->coinb2bin = ckzalloc(128);
 	memcpy(wb->coinb2bin, "\x0a\x63\x6b\x70\x6f\x6f\x6c", 7);
 	wb->coinb2len = 7;
 	if (ckp->btcsig) {
@@ -1841,7 +1841,7 @@ static json_t *__stratum_notify(bool clean)
 			current_workbase->prevhash,
 			current_workbase->coinb1,
 			current_workbase->coinb2,
-			json_copy(current_workbase->merkle_array),
+			json_deep_copy(current_workbase->merkle_array),
 			current_workbase->bbversion,
 			current_workbase->nbit,
 			current_workbase->ntime,