From 6cf66bb0a02f3993394c0408c2865bfaf2756f21 Mon Sep 17 00:00:00 2001
From: =?utf8?q?G=C3=BCnther=20Kelleter?= <guenther.kelleter@devolo.de>
Date: Thu, 3 Nov 2016 13:40:53 +0100
Subject: [PATCH] system-linux: check for open failure
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit

Signed-off-by: Günther Kelleter <guenther.kelleter@devolo.de>
---
 system-linux.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/system-linux.c b/system-linux.c
index 6e4a194..a038987 100644
--- a/system-linux.c
+++ b/system-linux.c
@@ -2489,6 +2489,8 @@ int system_update_ipv6_mtu(struct device *dev, int mtu)
 			dev->ifname);
 
 	int fd = open(buf, O_RDWR);
+	if (fd < 0)
+		return ret;
 
 	if (!mtu) {
 		ssize_t len = read(fd, buf, sizeof(buf) - 1);
-- 
2.30.2