Return-path: Received: from nbd.name ([46.4.11.11]:56798 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752855Ab3DPKwU (ORCPT ); Tue, 16 Apr 2013 06:52:20 -0400 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com, mcgrof@qca.qualcomm.com Subject: [PATCH 2/2] ath9k: always set common->macaddr to the MAC adress of a virtual interface Date: Tue, 16 Apr 2013 12:51:57 +0200 Message-Id: <1366109517-64645-2-git-send-email-nbd@openwrt.org> (sfid-20130416_125224_866185_80C078F3) In-Reply-To: <1366109517-64645-1-git-send-email-nbd@openwrt.org> References: <1366109517-64645-1-git-send-email-nbd@openwrt.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: In some cases it can be useful to change the MAC address of a virtual interface to something that's completely different from the EEPROM stored MAC address. In this case it is a bad idea to use the EEPROM MAC address for calculating the BSSID mask, as that would make it too wide. In one case a few devices have been observed to send ACKs for many packets on the channel not directed at them, which results in a neat Denial of Service attack on the channel. Signed-off-by: Felix Fietkau --- drivers/net/wireless/ath/ath9k/ath9k.h | 7 +++---- drivers/net/wireless/ath/ath9k/main.c | 9 +++++++-- 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index 86d3572..1915f12 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -658,11 +658,10 @@ enum sc_op_flags { struct ath_rate_table; struct ath9k_vif_iter_data { - const u8 *hw_macaddr; /* phy's hardware address, set - * before starting iteration for - * valid bssid mask. - */ + u8 hw_macaddr[ETH_ALEN]; /* address of the first vif */ u8 mask[ETH_ALEN]; /* bssid mask */ + bool has_hw_macaddr; + int naps; /* number of AP vifs */ int nmeshes; /* number of mesh vifs */ int nstations; /* number of station vifs */ diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c index a383483..6963862 100644 --- a/drivers/net/wireless/ath/ath9k/main.c +++ b/drivers/net/wireless/ath/ath9k/main.c @@ -839,10 +839,14 @@ static void ath9k_vif_iter(void *data, u8 *mac, struct ieee80211_vif *vif) struct ath9k_vif_iter_data *iter_data = data; int i; - if (iter_data->hw_macaddr) + if (iter_data->has_hw_macaddr) { for (i = 0; i < ETH_ALEN; i++) iter_data->mask[i] &= ~(iter_data->hw_macaddr[i] ^ mac[i]); + } else { + memcpy(iter_data->hw_macaddr, mac, ETH_ALEN); + iter_data->has_hw_macaddr = true; + } switch (vif->type) { case NL80211_IFTYPE_AP: @@ -891,7 +895,6 @@ void ath9k_calculate_iter_data(struct ieee80211_hw *hw, * together with the BSSID mask when matching addresses. */ memset(iter_data, 0, sizeof(*iter_data)); - iter_data->hw_macaddr = common->macaddr; memset(&iter_data->mask, 0xff, ETH_ALEN); if (vif) @@ -901,6 +904,8 @@ void ath9k_calculate_iter_data(struct ieee80211_hw *hw, ieee80211_iterate_active_interfaces_atomic( sc->hw, IEEE80211_IFACE_ITER_RESUME_ALL, ath9k_vif_iter, iter_data); + + memcpy(common->macaddr, iter_data->hw_macaddr, ETH_ALEN); } /* Called with sc->mutex held. */ -- 1.8.0.2