[ 3.5.y.z extended stable ] Patch "crypto: algif - suppress sending source address information" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    crypto: algif - suppress sending source address information

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 295f5324f29eb8253463827247aadacc502dd05d Mon Sep 17 00:00:00 2001
From: Mathias Krause <minipli at googlemail.com>
Date: Sun, 7 Apr 2013 14:05:39 +0200
Subject: [PATCH] crypto: algif - suppress sending source address information
 in recvmsg

commit 72a763d805a48ac8c0bf48fdb510e84c12de51fe upstream.

The current code does not set the msg_namelen member to 0 and therefore
makes net/socket.c leak the local sockaddr_storage variable to userland
-- 128 bytes of kernel stack memory. Fix that.

Signed-off-by: Mathias Krause <minipli at googlemail.com>
Signed-off-by: Herbert Xu <herbert at gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 crypto/algif_hash.c     | 2 ++
 crypto/algif_skcipher.c | 1 +
 2 files changed, 3 insertions(+)

diff --git a/crypto/algif_hash.c b/crypto/algif_hash.c
index ef5356c..0262210 100644
--- a/crypto/algif_hash.c
+++ b/crypto/algif_hash.c
@@ -161,6 +161,8 @@ static int hash_recvmsg(struct kiocb *unused, struct socket *sock,
 	else if (len < ds)
 		msg->msg_flags |= MSG_TRUNC;

+	msg->msg_namelen = 0;
+
 	lock_sock(sk);
 	if (ctx->more) {
 		ctx->more = 0;
diff --git a/crypto/algif_skcipher.c b/crypto/algif_skcipher.c
index 6a6dfc0..a1c4f0a 100644
--- a/crypto/algif_skcipher.c
+++ b/crypto/algif_skcipher.c
@@ -432,6 +432,7 @@ static int skcipher_recvmsg(struct kiocb *unused, struct socket *sock,
 	long copied = 0;

 	lock_sock(sk);
+	msg->msg_namelen = 0;
 	for (iov = msg->msg_iov, iovlen = msg->msg_iovlen; iovlen > 0;
 	     iovlen--, iov++) {
 		unsigned long seglen = iov->iov_len;
--
1.8.1.2