From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:48076 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726650AbeJSCA0 (ORCPT ); Thu, 18 Oct 2018 22:00:26 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sven Eckelmann , Antonio Quartulli , Simon Wunderlich , Sasha Levin Subject: [PATCH 4.18 06/53] batman-adv: Avoid probe ELP information leak Date: Thu, 18 Oct 2018 19:53:59 +0200 Message-Id: <20181018175417.819370203@linuxfoundation.org> In-Reply-To: <20181018175416.561567978@linuxfoundation.org> References: <20181018175416.561567978@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann [ Upstream commit 88d0895d0ea9d4431507d576c963f2ff9918144d ] The probe ELPs for WiFi interfaces are expanded to contain at least BATADV_ELP_MIN_PROBE_SIZE bytes. This is usually a lot more than the number of bytes which the template ELP packet requires. These extra padding bytes were not initialized and thus could contain data which were previously stored at the same location. It is therefore required to set it to some predefined or random values to avoid leaking private information from the system transmitting these kind of packets. Fixes: e4623c913508 ("batman-adv: Avoid probe ELP information leak") Signed-off-by: Sven Eckelmann Acked-by: Antonio Quartulli Signed-off-by: Simon Wunderlich Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- net/batman-adv/bat_v_elp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/batman-adv/bat_v_elp.c +++ b/net/batman-adv/bat_v_elp.c @@ -241,7 +241,7 @@ batadv_v_elp_wifi_neigh_probe(struct bat * the packet to be exactly of that size to make the link * throughput estimation effective. */ - skb_put(skb, probe_len - hard_iface->bat_v.elp_skb->len); + skb_put_zero(skb, probe_len - hard_iface->bat_v.elp_skb->len); batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "Sending unicast (probe) ELP packet on interface %s to %pM\n",