Return-path: Received: from mo4-p00-ob.smtp.rzone.de ([81.169.146.163]:63828 "EHLO mo4-p00-ob.smtp.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755340AbcJLQiT (ORCPT ); Wed, 12 Oct 2016 12:38:19 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Date: Wed, 12 Oct 2016 18:31:50 +0200 From: michael-dev To: Johannes Berg Cc: linux-wireless@vger.kernel.org, projekt-wlan@fem.tu-ilmenau.de, Felix Fietkau Subject: Re: [PATCH v2] mac80211: fix A-MSDU outer SA/DA In-Reply-To: <1476275121.5271.28.camel@sipsolutions.net> References: <1476269870-32007-1-git-send-email-michael-dev@fami-braun.de> <1476275121.5271.28.camel@sipsolutions.net> Message-ID: (sfid-20161012_183823_945747_A58ED6BC) Sender: linux-wireless-owner@vger.kernel.org List-ID: Am 12.10.2016 14:25, schrieb Johannes Berg: > So, I actually think my first instinct that you were erroneously > changing the inner header *was* right. You're right. > Seems like this code should be inserted towards the end of > ieee80211_amsdu_aggregate() instead, where it's adding the RFC 1042 > header? I'm not convinced. ieee80211_amsdu_aggregate handles two skbs: the "skb" var and the "head" var. The skb is appended to the frag list of head by setting frag_tail and does not appear to have an ieee80211_hdr, as memmove is only 2 * ETH_ALEN. Additionally, the rfc1042_header is written after 2 bytes containing subframe_len, so it looks like an A-MSDU subframe with rfc1042_header is inserted at the beginning of the inner MSDU. Only the head skb is processed by ieee80211_amsdu_prepare_head and appears to have an 802.11 header. So its da/sa address should be changed. Regards, M. Braun