| From 84469a45a1bedec9918e94ab2f78c5dc0739e4a7 Mon Sep 17 00:00:00 2001 |
| From: Luciano Coelho <luciano.coelho@intel.com> |
| Date: Tue, 28 Oct 2014 13:33:04 +0200 |
| Subject: mac80211: use secondary channel offset IE also beacons during CSA |
| |
| From: Luciano Coelho <luciano.coelho@intel.com> |
| |
| commit 84469a45a1bedec9918e94ab2f78c5dc0739e4a7 upstream. |
| |
| If we are switching from an HT40+ to an HT40- channel (or vice-versa), |
| we need the secondary channel offset IE to specify what is the |
| post-CSA offset to be used. This applies both to beacons and to probe |
| responses. |
| |
| In ieee80211_parse_ch_switch_ie() we were ignoring this IE from |
| beacons and using the *current* HT information IE instead. This was |
| causing us to use the same offset as before the switch. |
| |
| Fix that by using the secondary channel offset IE also for beacons and |
| don't ever use the pre-switch offset. Additionally, remove the |
| "beacon" argument from ieee80211_parse_ch_switch_ie(), since it's not |
| needed anymore. |
| |
| Reported-by: Jouni Malinen <j@w1.fi> |
| Signed-off-by: Luciano Coelho <luciano.coelho@intel.com> |
| Signed-off-by: Johannes Berg <johannes.berg@intel.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| net/mac80211/ibss.c | 2 +- |
| net/mac80211/ieee80211_i.h | 3 +-- |
| net/mac80211/mesh.c | 2 +- |
| net/mac80211/mlme.c | 2 +- |
| net/mac80211/spectmgmt.c | 18 ++++++------------ |
| 5 files changed, 10 insertions(+), 17 deletions(-) |
| |
| --- a/net/mac80211/ibss.c |
| +++ b/net/mac80211/ibss.c |
| @@ -804,7 +804,7 @@ ieee80211_ibss_process_chanswitch(struct |
| |
| memset(¶ms, 0, sizeof(params)); |
| memset(&csa_ie, 0, sizeof(csa_ie)); |
| - err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, |
| + err = ieee80211_parse_ch_switch_ie(sdata, elems, |
| ifibss->chandef.chan->band, |
| sta_flags, ifibss->bssid, &csa_ie); |
| /* can't switch to destination channel, fail */ |
| --- a/net/mac80211/ieee80211_i.h |
| +++ b/net/mac80211/ieee80211_i.h |
| @@ -1639,7 +1639,6 @@ void ieee80211_process_measurement_req(s |
| * ieee80211_parse_ch_switch_ie - parses channel switch IEs |
| * @sdata: the sdata of the interface which has received the frame |
| * @elems: parsed 802.11 elements received with the frame |
| - * @beacon: indicates if the frame was a beacon or probe response |
| * @current_band: indicates the current band |
| * @sta_flags: contains information about own capabilities and restrictions |
| * to decide which channel switch announcements can be accepted. Only the |
| @@ -1653,7 +1652,7 @@ void ieee80211_process_measurement_req(s |
| * Return: 0 on success, <0 on error and >0 if there is nothing to parse. |
| */ |
| int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata, |
| - struct ieee802_11_elems *elems, bool beacon, |
| + struct ieee802_11_elems *elems, |
| enum ieee80211_band current_band, |
| u32 sta_flags, u8 *bssid, |
| struct ieee80211_csa_ie *csa_ie); |
| --- a/net/mac80211/mesh.c |
| +++ b/net/mac80211/mesh.c |
| @@ -874,7 +874,7 @@ ieee80211_mesh_process_chnswitch(struct |
| |
| memset(¶ms, 0, sizeof(params)); |
| memset(&csa_ie, 0, sizeof(csa_ie)); |
| - err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band, |
| + err = ieee80211_parse_ch_switch_ie(sdata, elems, band, |
| sta_flags, sdata->vif.addr, |
| &csa_ie); |
| if (err < 0) |
| --- a/net/mac80211/mlme.c |
| +++ b/net/mac80211/mlme.c |
| @@ -1058,7 +1058,7 @@ ieee80211_sta_process_chanswitch(struct |
| |
| current_band = cbss->channel->band; |
| memset(&csa_ie, 0, sizeof(csa_ie)); |
| - res = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, current_band, |
| + res = ieee80211_parse_ch_switch_ie(sdata, elems, current_band, |
| ifmgd->flags, |
| ifmgd->associated->bssid, &csa_ie); |
| if (res < 0) |
| --- a/net/mac80211/spectmgmt.c |
| +++ b/net/mac80211/spectmgmt.c |
| @@ -22,7 +22,7 @@ |
| #include "wme.h" |
| |
| int ieee80211_parse_ch_switch_ie(struct ieee80211_sub_if_data *sdata, |
| - struct ieee802_11_elems *elems, bool beacon, |
| + struct ieee802_11_elems *elems, |
| enum ieee80211_band current_band, |
| u32 sta_flags, u8 *bssid, |
| struct ieee80211_csa_ie *csa_ie) |
| @@ -91,19 +91,13 @@ int ieee80211_parse_ch_switch_ie(struct |
| return -EINVAL; |
| } |
| |
| - if (!beacon && sec_chan_offs) { |
| + if (sec_chan_offs) { |
| secondary_channel_offset = sec_chan_offs->sec_chan_offs; |
| - } else if (beacon && ht_oper) { |
| - secondary_channel_offset = |
| - ht_oper->ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET; |
| } else if (!(sta_flags & IEEE80211_STA_DISABLE_HT)) { |
| - /* If it's not a beacon, HT is enabled and the IE not present, |
| - * it's 20 MHz, 802.11-2012 8.5.2.6: |
| - * This element [the Secondary Channel Offset Element] is |
| - * present when switching to a 40 MHz channel. It may be |
| - * present when switching to a 20 MHz channel (in which |
| - * case the secondary channel offset is set to SCN). |
| - */ |
| + /* If the secondary channel offset IE is not present, |
| + * we can't know what's the post-CSA offset, so the |
| + * best we can do is use 20MHz. |
| + */ |
| secondary_channel_offset = IEEE80211_HT_PARAM_CHA_SEC_NONE; |
| } |
| |
