[PATCH 4/4] lwip: Fix a buffer overflow and clear compiler warnings

[Joan Lledó]

GCC 8 new warning -Wstringop-truncation detected some buffer overflows.

* lwip/options.c (parse_opt): Fix the buffer overflow.
* lwip/pfinet-ops.c (dev_ifconf): Likewise.
---
 lwip/options.c    | 2 +-
 lwip/pfinet-ops.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lwip/options.c b/lwip/options.c
index 6591ac52..d35b9f32 100644
--- a/lwip/options.c
+++ b/lwip/options.c
@@ -133,7 +133,7 @@ parse_opt (int opt, char *arg, struct argp_state *state)
        }
       in = h->curint;
 
-      strncpy (in->dev_name, arg, DEV_NAME_LEN);
+      strncpy (in->dev_name, arg, sizeof(in->dev_name)-1);
       break;
 
     case 'a':
diff --git a/lwip/pfinet-ops.c b/lwip/pfinet-ops.c
index 56b7dcd1..1af2a3fe 100644
--- a/lwip/pfinet-ops.c
+++ b/lwip/pfinet-ops.c
@@ -61,7 +61,7 @@ dev_ifconf (struct ifconf *ifc)
          memset (ifr, 0, sizeof (struct ifreq));
 
          strncpy (ifr->ifr_name, netif_get_state (netif)->devname,
-                  strlen (netif_get_state (netif)->devname) + 1);
+                  sizeof (ifr->ifr_name)-1);
          saddr->sin_len = sizeof (struct sockaddr_in);
          saddr->sin_family = AF_INET;
          saddr->sin_addr.s_addr = netif_ip4_addr (netif)->addr;
-- 
2.11.0