From df0bca049d01c0ee94afb7cd5dfd959541e6c8da Mon Sep 17 00:00:00 2001
From: =?utf8?q?Cl=C3=A9ment=20Lecigne?= <clement.lecigne@netasq.com>
Date: Thu, 12 Feb 2009 16:59:09 -0800
Subject: [PATCH] net: 4 bytes kernel memory disclosure in SO_BSDCOMPAT gsopt
 try #2
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In function sock_getsockopt() located in net/core/sock.c, optval v.val
is not correctly initialized and directly returned in userland in case
we have SO_BSDCOMPAT option set.

This dummy code should trigger the bug:

int main(void)
{
	unsigned char buf[4] = { 0, 0, 0, 0 };
	int len;
	int sock;
	sock = socket(33, 2, 2);
	getsockopt(sock, 1, SO_BSDCOMPAT, &buf, &len);
	printf("%x%x%x%x\n", buf[0], buf[1], buf[2], buf[3]);
	close(sock);
}

Here is a patch that fix this bug by initalizing v.val just after its
declaration.

Signed-off-by: Clément Lecigne <clement.lecigne@netasq.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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