odhcpd: fix strncpy bounds

[project/odhcpd.git] / src / dhcpv4.c

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index db5f138..35a3ad0 100644 (file)
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -779,8 +779,10 @@ static void handle_dhcpv4(void *addr, void *data, size_t len,
                }
        }
 
-       struct ifreq ifr = {.ifr_name = ""};
-       strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name));
+       struct ifreq ifr;
+
+       memset(&ifr, 0, sizeof(ifr));
+       strncpy(ifr.ifr_name, iface->ifname, sizeof(ifr.ifr_name) - 1);
 
        if (!ioctl(sock, SIOCGIFMTU, &ifr)) {
                uint16_t mtu = htons(ifr.ifr_mtu);