From c5b33851d73d3087ce7bdda2a3113a205d584b17 Mon Sep 17 00:00:00 2001
From: Paul Sokolovsky <pfalcon@users.sourceforge.net>
Date: Sun, 18 Sep 2016 14:13:38 +0300
Subject: [PATCH] zephyr/modsocket: socket_write: Send only data fitting in a
 netbuf.

---
 zephyr/modsocket.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/zephyr/modsocket.c b/zephyr/modsocket.c
index b286d7e6f..eb414fc0b 100644
--- a/zephyr/modsocket.c
+++ b/zephyr/modsocket.c
@@ -184,6 +184,9 @@ STATIC mp_uint_t socket_write(mp_obj_t self_in, const void *buf, mp_uint_t len,
     }
 
     struct net_buf *netbuf = ip_buf_get_tx(self->sock);
+    if (len > net_buf_tailroom(netbuf)) {
+        len = net_buf_tailroom(netbuf);
+    }
     uint8_t *ptr = net_buf_add(netbuf, len);
     memcpy(ptr, buf, len);
     ip_buf_appdatalen(netbuf) = len;