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

manuels · davem330 · commit 84a7c0b1db1c · 2014-06-11T00:12:04.000-07:00
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 &lt;manuel.schoelling@gmx.de&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
@@ -149,7 +149,9 @@ 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;
 
