--- embedaddon/dnsmasq/src/tftp.c	2014/06/15 16:31:38	1.1.1.2
+++ embedaddon/dnsmasq/src/tftp.c	2016/11/02 09:57:01	1.1.1.3
@@ -1,4 +1,4 @@
-/* dnsmasq is Copyright (c) 2000-2014 Simon Kelley
+/* dnsmasq is Copyright (c) 2000-2016 Simon Kelley
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -103,8 +103,10 @@ void tftp_request(struct listener *listen, time_t now)
       if (listen->iface)
 	{
 	  addr = listen->iface->addr;
-	  mtu = listen->iface->mtu;
 	  name = listen->iface->name;
+	  mtu = listen->iface->mtu;
+	  if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
+	    mtu = daemon->tftp_mtu;
 	}
       else
 	{
@@ -234,9 +236,17 @@ void tftp_request(struct listener *listen, time_t now)
 
       strncpy(ifr.ifr_name, name, IF_NAMESIZE);
       if (ioctl(listen->tftpfd, SIOCGIFMTU, &ifr) != -1)
-	mtu = ifr.ifr_mtu;      
+	{
+	  mtu = ifr.ifr_mtu;  
+	  if (daemon->tftp_mtu != 0 && daemon->tftp_mtu < mtu)
+	    mtu = daemon->tftp_mtu;    
+	}
     }
-  
+
+  /* Failed to get interface mtu - can use configured value. */
+  if (mtu == 0)
+    mtu = daemon->tftp_mtu;
+
   if (name)
     {
       /* check for per-interface prefix */ 
@@ -336,14 +346,15 @@ void tftp_request(struct listener *listen, time_t now)
 	    {
 	      if ((opt = next(&p, end)) && !option_bool(OPT_TFTP_NOBLOCK))
 		{
+		  /* 32 bytes for IP, UDP and TFTP headers, 52 bytes for IPv6 */
+		  int overhead = (listen->family == AF_INET) ? 32 : 52;
 		  transfer->blocksize = atoi(opt);
 		  if (transfer->blocksize < 1)
 		    transfer->blocksize = 1;
 		  if (transfer->blocksize > (unsigned)daemon->packet_buff_sz - 4)
 		    transfer->blocksize = (unsigned)daemon->packet_buff_sz - 4;
-		  /* 32 bytes for IP, UDP and TFTP headers */
-		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - 32)
-		    transfer->blocksize = (unsigned)mtu - 32;
+		  if (mtu != 0 && transfer->blocksize > (unsigned)mtu - overhead)
+		    transfer->blocksize = (unsigned)mtu - overhead;
 		  transfer->opt_blocksize = 1;
 		  transfer->block = 0;
 		}
@@ -502,7 +513,7 @@ static struct tftp_file *check_tftp_fileperm(ssize_t *
   return NULL;
 }
 
-void check_tftp_listeners(fd_set *rset, time_t now)
+void check_tftp_listeners(time_t now)
 {
   struct tftp_transfer *transfer, *tmp, **up;
   ssize_t len;
@@ -518,7 +529,7 @@ void check_tftp_listeners(fd_set *rset, time_t now)
       
       prettyprint_addr(&transfer->peer, daemon->addrbuff);
      
-      if (FD_ISSET(transfer->sockfd, rset))
+      if (poll_check(transfer->sockfd, POLLIN))
 	{
 	  /* we overwrote the buffer... */
 	  daemon->srv_save = NULL;