[3.11.y.z extended stable] Patch "dns_resolver: assure that dns_query() result is null-terminated" has been added to staging queue

[Luis Henriques]

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

    dns_resolver: assure that dns_query() result is null-terminated

to the linux-3.11.y-queue branch of the 3.11.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-3.11.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 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From b9590327c3ed7013b644128c314f8d416dcca3f3 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Manuel=20Sch=C3=B6lling?= <manuel.schoelling at gmx.de>
Date: Sat, 7 Jun 2014 23:57:25 +0200
Subject: dns_resolver: assure that dns_query() result is null-terminated
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

commit 84a7c0b1db1c17d5ded8d3800228a608e1070b40 upstream.

dns_query() credulously assumes that keys are null-terminated and
returns a copy of a memory block that is off by one.

Signed-off-by: Manuel Schölling <manuel.schoelling at gmx.de>
Signed-off-by: David S. Miller <davem at davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 net/dns_resolver/dns_query.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index c32be292c7e3..ede0e2d7412e 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -150,7 +150,9 @@ int dns_query(const char *type, const char *name, size_t namelen,
 	if (!*_result)
 		goto put;

-	memcpy(*_result, upayload->data, len + 1);
+	memcpy(*_result, upayload->data, len);
+	*_result[len] = '\0';
+
 	if (_expiry)
 		*_expiry = rkey->expiry;

--
1.9.1