Blame SOURCES/0133-trim-arp-packets-with-abnormal-size.patch

39700a
From cf2e819b7059f199075b099260983e8108eea74a Mon Sep 17 00:00:00 2001
606ea6
From: Paulo Flabiano Smorigo <pfsmorigo@br.ibm.com>
606ea6
Date: Wed, 5 Feb 2014 09:42:42 -0200
39700a
Subject: [PATCH 133/143] trim arp packets with abnormal size
606ea6
606ea6
GRUB uses arp request to create the arp response. If the incoming packet
606ea6
is foobared, GRUB needs to trim the arp response packet before sending it.
606ea6
---
606ea6
 grub-core/net/arp.c | 6 ++++++
606ea6
 1 file changed, 6 insertions(+)
606ea6
606ea6
diff --git a/grub-core/net/arp.c b/grub-core/net/arp.c
606ea6
index d62d0cc..77581f4 100644
606ea6
--- a/grub-core/net/arp.c
606ea6
+++ b/grub-core/net/arp.c
606ea6
@@ -162,6 +162,12 @@ grub_net_arp_receive (struct grub_net_buff *nb,
606ea6
     if (grub_net_addr_cmp (&inf->address, &target_addr) == 0
606ea6
 	&& grub_be_to_cpu16 (arp_header->op) == ARP_REQUEST)
606ea6
       {
606ea6
+        if ((nb->tail - nb->data) > 50)
606ea6
+          {
606ea6
+            grub_dprintf ("net", "arp packet with abnormal size (%ld bytes).\n",
606ea6
+                         nb->tail - nb->data);
606ea6
+            nb->tail = nb->data + 50;
606ea6
+          }
606ea6
 	grub_net_link_level_address_t target;
606ea6
 	/* We've already checked that pln is either 4 or 16.  */
606ea6
 	char tmp[16];
606ea6
-- 
39700a
1.9.3
39700a