From cc2c6564492b2a5f570d08d127c1496cc185a5f5 Mon Sep 17 00:00:00 2001
From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 6 Jun 2011 22:42:06 -0700
Subject: af_packet: prevent information leak

[ Upstream commit 13fcb7bd322164c67926ffe272846d4860196dc6 ]

In 2.6.27, commit 393e52e33c6c2 (packet: deliver VLAN TCI to userspace)
added a small information leak.

Add padding field and make sure its zeroed before copy to user.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 include/linux/if_packet.h | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'include')

diff --git a/include/linux/if_packet.h b/include/linux/if_packet.h
index dea7d6b7cf98..8851a016d661 100644
--- a/include/linux/if_packet.h
+++ b/include/linux/if_packet.h
@@ -63,6 +63,7 @@ struct tpacket_auxdata
 	__u16		tp_mac;
 	__u16		tp_net;
 	__u16		tp_vlan_tci;
+	__u16		tp_padding;
 };
 
 /* Rx ring - header status */
@@ -103,6 +104,7 @@ struct tpacket2_hdr
 	__u32		tp_sec;
 	__u32		tp_nsec;
 	__u16		tp_vlan_tci;
+	__u16		tp_padding;
 };
 
 #define TPACKET2_HDRLEN		(TPACKET_ALIGN(sizeof(struct tpacket2_hdr)) + sizeof(struct sockaddr_ll))
-- 
cgit v1.2.3