2011-03-17 11:40:20

by Vasily Kulikov

[permalink] [raw]
Subject: [PATCH] econet: 4 byte infoleak to the network

struct aunhdr has 4 padding bytes between 'pad' and 'handle' fields on
x86_64. These bytes are not initialized in the variable 'ah' before
sending 'ah' to the network. This leads to 4 bytes kernel stack
infoleak.

This bug was introduced before the git epoch.

Signed-off-by: Vasiliy Kulikov <[email protected]>
---
net/econet/af_econet.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/econet/af_econet.c b/net/econet/af_econet.c
index 0c28263..116d3fd 100644
--- a/net/econet/af_econet.c
+++ b/net/econet/af_econet.c
@@ -435,10 +435,10 @@ static int econet_sendmsg(struct kiocb *iocb, struct socket *sock,
udpdest.sin_addr.s_addr = htonl(network | addr.station);
}

+ memset(&ah, 0, sizeof(ah));
ah.port = port;
ah.cb = cb & 0x7f;
ah.code = 2; /* magic */
- ah.pad = 0;

/* tack our header on the front of the iovec */
size = sizeof(struct aunhdr);
--
1.7.0.4


2011-03-17 12:33:21

by Phil Blundell

[permalink] [raw]
Subject: Re: [PATCH] econet: 4 byte infoleak to the network

On Thu, 2011-03-17 at 14:40 +0300, Vasiliy Kulikov wrote:
> struct aunhdr has 4 padding bytes between 'pad' and 'handle' fields on
> x86_64. These bytes are not initialized in the variable 'ah' before
> sending 'ah' to the network. This leads to 4 bytes kernel stack
> infoleak.
>
> This bug was introduced before the git epoch.
>
> Signed-off-by: Vasiliy Kulikov <[email protected]>

Well spotted. Thanks for the patch.

Acked-by: Phil Blundell <[email protected]>

p.

2011-03-18 22:15:00

by David Miller

[permalink] [raw]
Subject: Re: [PATCH] econet: 4 byte infoleak to the network

From: Phil Blundell <[email protected]>
Date: Thu, 17 Mar 2011 11:50:01 +0000

> On Thu, 2011-03-17 at 14:40 +0300, Vasiliy Kulikov wrote:
>> struct aunhdr has 4 padding bytes between 'pad' and 'handle' fields on
>> x86_64. These bytes are not initialized in the variable 'ah' before
>> sending 'ah' to the network. This leads to 4 bytes kernel stack
>> infoleak.
>>
>> This bug was introduced before the git epoch.
>>
>> Signed-off-by: Vasiliy Kulikov <[email protected]>
>
> Well spotted. Thanks for the patch.
>
> Acked-by: Phil Blundell <[email protected]>

Applied.