dhcp: Clear flags

Do not assume that mem_malloc() returns cleared memory.

src/core/ipv4/autoip.c

@@ -223,9 +223,10 @@ autoip_conflict_callback(struct netif *netif, acd_callback_enum_t state)
       autoip_restart(netif);
       break;
     case ACD_DECLINE:
-      /* "delete" conflicting address so a new one will be selected in
-       * autoip_start() */
+      /* "delete" conflicting address and increment tried addr so a new one
+       * will be selected in autoip_start() */
       ip4_addr_set_any(&autoip->llipaddr);
+      autoip->tried_llipaddr++;
       autoip_stop(netif);
       break;
       default:

src/core/ipv4/dhcp.c

@@ -831,6 +831,8 @@ dhcp_start(struct netif *netif)
       return ERR_MEM;
     }
 
+    /* clear the flags, the rest is cleared below */
+    dhcp->flags = 0;
     /* store this dhcp client in the netif */
     netif_set_client_data(netif, LWIP_NETIF_CLIENT_DATA_INDEX_DHCP, dhcp);
     LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_start(): allocated dhcp\n"));

src/core/tcp_in.c

@@ -1993,17 +1993,17 @@ tcp_parseopt(struct tcp_pcb *pcb)
             return;
           }
           /* TCP timestamp option with valid length */
-          tsval = tcp_get_next_optbyte();
-          tsval |= (tcp_get_next_optbyte() << 8);
+          tsval = (tcp_get_next_optbyte() << 24);
           tsval |= (tcp_get_next_optbyte() << 16);
-          tsval |= (tcp_get_next_optbyte() << 24);
+          tsval |= (tcp_get_next_optbyte() << 8);
+          tsval |= tcp_get_next_optbyte();
           if (flags & TCP_SYN) {
-            pcb->ts_recent = lwip_ntohl(tsval);
+            pcb->ts_recent = tsval;
             /* Enable sending timestamps in every segment now that we know
                the remote host supports it. */
             tcp_set_flags(pcb, TF_TIMESTAMP);
           } else if (TCP_SEQ_BETWEEN(pcb->ts_lastacksent, seqno, seqno + tcplen)) {
-            pcb->ts_recent = lwip_ntohl(tsval);
+            pcb->ts_recent = tsval;
           }
           /* Advance to next option (6 bytes already read) */
           tcp_optidx += LWIP_TCP_OPT_LEN_TS - 6;