Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751798AbcKYJCF (ORCPT ); Fri, 25 Nov 2016 04:02:05 -0500 Received: from mx2.suse.de ([195.135.220.15]:45346 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752480AbcKYIbH (ORCPT ); Fri, 25 Nov 2016 03:31:07 -0500 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Johannes Berg , Jiri Slaby Subject: [PATCH 3.12 034/127] mac80211: discard multicast and 4-addr A-MSDUs Date: Fri, 25 Nov 2016 09:29:07 +0100 Message-Id: <56ccac941c5668cc3e3ac5bfa119487ecd5f65f9.1480062521.git.jslaby@suse.cz> X-Mailer: git-send-email 2.10.2 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2191 Lines: 66 From: Johannes Berg 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit ea720935cf6686f72def9d322298bf7e9bd53377 upstream. In mac80211, multicast A-MSDUs are accepted in many cases that they shouldn't be accepted in: * drop A-MSDUs with a multicast A1 (RA), as required by the spec in 9.11 (802.11-2012 version) * drop A-MSDUs with a 4-addr header, since the fourth address can't actually be useful for them; unless 4-address frame format is actually requested, even though the fourth address is still not useful in this case, but ignored Accepting the first case, in particular, is very problematic since it allows anyone else with possession of a GTK to send unicast frames encapsulated in a multicast A-MSDU, even when the AP has client isolation enabled. Signed-off-by: Johannes Berg Signed-off-by: Jiri Slaby --- net/mac80211/rx.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 834a41830778..4003bd682e06 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -2007,16 +2007,22 @@ ieee80211_rx_h_amsdu(struct ieee80211_rx_data *rx) if (!(status->rx_flags & IEEE80211_RX_AMSDU)) return RX_CONTINUE; - if (ieee80211_has_a4(hdr->frame_control) && - rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - !rx->sdata->u.vlan.sta) - return RX_DROP_UNUSABLE; + if (unlikely(ieee80211_has_a4(hdr->frame_control))) { + switch (rx->sdata->vif.type) { + case NL80211_IFTYPE_AP_VLAN: + if (!rx->sdata->u.vlan.sta) + return RX_DROP_UNUSABLE; + break; + case NL80211_IFTYPE_STATION: + if (!rx->sdata->u.mgd.use_4addr) + return RX_DROP_UNUSABLE; + break; + default: + return RX_DROP_UNUSABLE; + } + } - if (is_multicast_ether_addr(hdr->addr1) && - ((rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN && - rx->sdata->u.vlan.sta) || - (rx->sdata->vif.type == NL80211_IFTYPE_STATION && - rx->sdata->u.mgd.use_4addr))) + if (is_multicast_ether_addr(hdr->addr1)) return RX_DROP_UNUSABLE; skb->dev = dev; -- 2.10.2