From 7c5d2a8bddeeca7e02d4614bb6722a0cff566465 Mon Sep 17 00:00:00 2001
From: chao an <anchao@xiaomi.com>
Date: Fri, 2 Jun 2023 14:14:01 +0800
Subject: [PATCH] usrsock/dns: add sanity check before send dns event

Signed-off-by: chao an <anchao@xiaomi.com>
---
 drivers/usrsock/usrsock_rpmsg_server.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/usrsock/usrsock_rpmsg_server.c b/drivers/usrsock/usrsock_rpmsg_server.c
index 26a49d6c920..821479bba14 100644
--- a/drivers/usrsock/usrsock_rpmsg_server.c
+++ b/drivers/usrsock/usrsock_rpmsg_server.c
@@ -941,6 +941,10 @@ static int usrsock_rpmsg_send_dns_event(FAR void *arg,
   uint32_t len;
 
   dns = rpmsg_get_tx_payload_buffer(ept, &len, true);
+  if (dns == NULL)
+    {
+      return -ENOMEM;
+    }
 
   dns->head.msgid = USRSOCK_RPMSG_DNS_EVENT;
   dns->head.flags = USRSOCK_MESSAGE_FLAG_EVENT;