commit c304a23b4e46a1f2adb59f2e134162cfbbf35e4f
author Manuel Schölling <manuel.schoelling@gmx.de> Sat Jun 07 23:57:25 2014 +0200
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> Mon Jul 28 07:06:45 2014 -0700
tree 67517cb28bef30df5c9a6b193c461f727b399c5d
parent 7670d47228460135a71d9d8c1f88543eba30988f

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

[ Upstream commit 84a7c0b1db1c17d5ded8d3800228a608e1070b40 ]

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@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/dns_resolver/dns_query.c

diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index c32be29..ede0e2d 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -150,7 +150,9 @@
 	if (!*_result)
 		goto put;
 
-	memcpy(*_result, upayload->data, len + 1);
+	memcpy(*_result, upayload->data, len);
+	*_result[len] = '\0';
+
 	if (_expiry)
 		*_expiry = rkey->expiry;