=== modified file 'grub-core/net/drivers/efi/efinet.c'
--- grub-core/net/drivers/efi/efinet.c	2012-04-29 16:43:22 +0000
+++ grub-core/net/drivers/efi/efinet.c	2012-05-03 19:35:35 +0000
@@ -54,6 +54,8 @@
     }
 }

+struct grub_net_buff *saved_nb;
+
 static struct grub_net_buff *
 get_card_packet (const struct grub_net_card *dev)
 {
@@ -63,9 +65,18 @@
   grub_efi_uintn_t bufsize = 1536;
   struct grub_net_buff *nb;

-  nb = grub_netbuff_alloc (bufsize + 2);
-  if (!nb)
-    return NULL;
+  if (saved_nb)
+    {
+      nb = saved_nb;
+      grub_netbuff_clear (nb);
+      saved_nb = NULL;
+    }
+  else
+    {
+      nb = grub_netbuff_alloc (bufsize + 2);
+      if (!nb)
+	return NULL;
+    }

   /* Reserve 2 bytes so that 2 + 14/18 bytes of ethernet header is divisible
      by 4. So that IP header is aligned on 4 bytes. */
@@ -100,13 +111,13 @@
     }
   if (st != GRUB_EFI_SUCCESS)
     {
-      grub_netbuff_free (nb);
+      saved_nb = nb;
       return NULL;
     }
   err = grub_netbuff_put (nb, bufsize);
   if (err)
     {
-      grub_netbuff_free (nb);
+      saved_nb = nb;
       return NULL;
     }

@@ -234,6 +245,9 @@
 {
   struct grub_net_card *card, *next;

+  if (saved_nb)
+    grub_netbuff_free (saved_nb);
+
   FOR_NET_CARDS_SAFE (card, next)
     if (card->driver == &efidriver)
       grub_net_card_unregister (card);

=== modified file 'grub-core/net/tftp.c'
--- grub-core/net/tftp.c	2012-02-12 18:11:06 +0000
+++ grub-core/net/tftp.c	2012-05-03 19:13:03 +0000
@@ -27,6 +27,7 @@
 #include <grub/file.h>
 #include <grub/priority_queue.h>
 #include <grub/i18n.h>
+#include <grub/env.h>

 GRUB_MOD_LICENSE ("GPLv3+");

@@ -288,6 +293,7 @@
   grub_err_t err;
   grub_uint8_t *nbd;
   grub_net_network_level_address_t addr;
+  const char *tftp_block_size;

   data = grub_zalloc (sizeof (*data));
   if (!data)
@@ -320,9 +326,12 @@
   rrqlen += grub_strlen ("blksize") + 1;
   rrq += grub_strlen ("blksize") + 1;

-  grub_strcpy (rrq, "1024");
-  rrqlen += grub_strlen ("1024") + 1;
-  rrq += grub_strlen ("1024") + 1;
+  tftp_block_size = grub_env_get ("tftp_block_size");
+  if (tftp_block_size == NULL)
+    tftp_block_size = "4096";
+  grub_strcpy (rrq, tftp_block_size);
+  rrqlen += grub_strlen (tftp_block_size) + 1;
+  rrq += grub_strlen (tftp_block_size) + 1;

   grub_strcpy (rrq, "tsize");
   rrqlen += grub_strlen ("tsize") + 1;