diff --git a/arch/sim/src/cmake/Toolchain.cmake b/arch/sim/src/cmake/Toolchain.cmake
index c4c0cff080a91..118b62bbc537b 100644
--- a/arch/sim/src/cmake/Toolchain.cmake
+++ b/arch/sim/src/cmake/Toolchain.cmake
@@ -148,6 +148,7 @@ if(NOT WIN32)
     -ffunction-sections
     -fdata-sections
     -Wall
+    -Wvla
     -Wshadow
     -Wundef
     -Wno-attributes
diff --git a/boards/sim/sim/sim/scripts/Make.defs b/boards/sim/sim/sim/scripts/Make.defs
index c56772dc04309..4b392c00171da 100644
--- a/boards/sim/sim/sim/scripts/Make.defs
+++ b/boards/sim/sim/sim/scripts/Make.defs
@@ -127,8 +127,8 @@ ARCHCXXFLAGS += -fvisibility=hidden
 ARCHCFLAGS += -ffunction-sections -fdata-sections
 ARCHCXXFLAGS += -ffunction-sections -fdata-sections
 
-ARCHCFLAGS += -Wall -Wstrict-prototypes -Wshadow -Wundef -Wno-attributes -Wno-unknown-pragmas
-ARCHCXXFLAGS += -Wall -Wshadow -Wundef -Wno-attributes -Wno-unknown-pragmas
+ARCHCFLAGS += -Wall -Wvla -Wstrict-prototypes -Wshadow -Wundef -Wno-attributes -Wno-unknown-pragmas
+ARCHCXXFLAGS += -Wall -Wvla -Wshadow -Wundef -Wno-attributes -Wno-unknown-pragmas
 
 ifneq ($(CONFIG_LIBCXXTOOLCHAIN),y)
   ARCHCXXFLAGS += -nostdinc++
diff --git a/net/usrsock/usrsock_sendmsg.c b/net/usrsock/usrsock_sendmsg.c
index 048791193327f..ab844a722d952 100644
--- a/net/usrsock/usrsock_sendmsg.c
+++ b/net/usrsock/usrsock_sendmsg.c
@@ -36,6 +36,7 @@
 #include <arch/irq.h>
 
 #include <sys/socket.h>
+#include <nuttx/kmalloc.h>
 #include <nuttx/net/net.h>
 #include <nuttx/net/usrsock.h>
 
@@ -142,9 +143,18 @@ static int do_sendto_request(FAR struct usrsock_conn_s *conn,
   {
   };
 
-  struct iovec bufs[2 + msg->msg_iovlen];
+  struct iovec *bufs;
+  size_t iovlen;
+  int ret;
   int i;
 
+  iovlen = 2 + msg->msg_iovlen;
+  bufs = kmm_malloc(sizeof(*bufs) * iovlen);
+  if (bufs == NULL)
+    {
+      return -ENOMEM;
+    }
+
   if (msg->msg_namelen > UINT16_MAX)
     {
       msg->msg_namelen = UINT16_MAX;
@@ -174,7 +184,9 @@ static int do_sendto_request(FAR struct usrsock_conn_s *conn,
 
   memcpy(&bufs[2], msg->msg_iov, sizeof(struct iovec) * msg->msg_iovlen);
 
-  return usrsock_do_request(conn, bufs, nitems(bufs));
+  ret = usrsock_do_request(conn, bufs, iovlen);
+  kmm_free(bufs);
+  return ret;
 }
 
 /****************************************************************************