From: Hans Dedecker <dedeckeh@gmail.com>
Date: Mon, 3 Jul 2017 14:39:21 +0000 (+0200)
Subject: dhcpv4: avoid segfault when there's no IPv4 prefix
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=a827fcad451996f1a7043b479d8c6162174b2038;p=project%2Fodhcpd.git

dhcpv4: avoid segfault when there's no IPv4 prefix

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>
---

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index c7ac058..b0a4603 100644
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -95,7 +95,8 @@ int setup_dhcpv4_interface(struct interface *iface, bool enable)
 			return -1;
 		}
 
-		uint32_t mask = iface->addr4[0].prefix ? htonl(~((1 << (32 - iface->addr4[0].prefix)) - 1)) : 0;
+		uint32_t mask = iface->addr4 && iface->addr4[0].prefix ?
+			htonl(~((1 << (32 - iface->addr4[0].prefix)) - 1)) : 0xffffffff;
 
 		/* Create a range if not specified */
 		if (!(iface->dhcpv4_start.s_addr & htonl(0xffff0000)) &&