From c32a0be89cc92a0649277774d1e7aebf349b8b49 Mon Sep 17 00:00:00 2001
From: Dennis Yurasov <dennis-y@yandex-team.ru>
Date: Tue, 24 Aug 2021 17:15:24 +0300
Subject: [PATCH] ndb_redis: fix SIGSEGV in redisc_check_auth

- Added the check for NULL pointer. When TCP session to redis reset,
  redisCommand function can return NULL pointer.
---
 src/modules/ndb_redis/redis_client.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/modules/ndb_redis/redis_client.c b/src/modules/ndb_redis/redis_client.c
index befb69ab79a..bb6adc20b13 100644
--- a/src/modules/ndb_redis/redis_client.c
+++ b/src/modules/ndb_redis/redis_client.c
@@ -1269,6 +1269,10 @@ int redisc_check_auth(redisc_server_t *rsrv, char *pass)
 	int retval = 0;
 
 	reply = redisCommand(rsrv->ctxRedis, "AUTH %s", pass);
+	if(!reply) {
+		LM_ERR("Redis authentication error\n");
+		return -1;
+	}
 	if (reply->type == REDIS_REPLY_ERROR) {
 		LM_ERR("Redis authentication error\n");
 		retval = -1;