From 4479004e6409087d1b4986881dc98c6c15dffb28 Mon Sep 17 00:00:00 2001 From: Tom Hughes Date: Mon, 29 Jun 2015 19:41:49 +0100 Subject: [PATCH 1/8] mac80211: clear subdir_stations when removing debugfs If we don't do this, and we then fail to recreate the debugfs directory during a mode change, then we will fail later trying to add stations to this now bogus directory: BUG: unable to handle kernel NULL pointer dereference at 0000006c IP: [] mutex_lock+0x12/0x30 Call Trace: [] start_creating+0x44/0xc0 [] debugfs_create_dir+0x13/0xf0 [] ieee80211_sta_debugfs_add+0x6e/0x490 [mac80211] Cc: stable@kernel.org Signed-off-by: Tom Hughes Signed-off-by: Johannes Berg --- net/mac80211/debugfs_netdev.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c index 29236e832e44..c09c0131bfa2 100644 --- a/net/mac80211/debugfs_netdev.c +++ b/net/mac80211/debugfs_netdev.c @@ -723,6 +723,7 @@ void ieee80211_debugfs_remove_netdev(struct ieee80211_sub_if_data *sdata) debugfs_remove_recursive(sdata->vif.debugfs_dir); sdata->vif.debugfs_dir = NULL; + sdata->debugfs.subdir_stations = NULL; } void ieee80211_debugfs_rename_netdev(struct ieee80211_sub_if_data *sdata) From e9de01907e3d1957591113daa3857c0bf01067ef Mon Sep 17 00:00:00 2001 From: Michal Kazior Date: Thu, 2 Jul 2015 09:59:56 +0200 Subject: [PATCH 2/8] mac80211: don't clear all tx flags when requeing When acting as AP and a PS-Poll frame is received associated station is marked as one in a Service Period. This state is kept until Tx status for released frame is reported. While a station is in Service Period PS-Poll frames are ignored. However if PS-Poll was received during A-MPDU teardown it was possible to have the to-be released frame re-queued back to pending queue. In such case the frame was stripped of 2 important flags: (a) IEEE80211_TX_CTL_NO_PS_BUFFER (b) IEEE80211_TX_STATUS_EOSP Stripping of (a) led to the frame that was to be released to be queued back to ps_tx_buf queue. If station remained to use only PS-Poll frames the re-queued frame (and new ones) was never actually transmitted because mac80211 would ignore subsequent PS-Poll frames due to station being in Service Period. There was nothing left to clear the Service Period bit (no xmit -> no tx status -> no SP end), i.e. the AP would have the station stuck in Service Period. Beacon TIM would repeatedly prompt station to poll for frames but it would get none. Once (a) is not stripped (b) becomes important because it's the main condition to clear the Service Period bit of the station when Tx status for the released frame is reported back. This problem was observed with ath9k acting as P2P GO in some testing scenarios but isn't limited to it. AP operation with mac80211 based Tx A-MPDU control combined with clients using PS-Poll frames is subject to this race. Signed-off-by: Michal Kazior Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 8410bb3bf5e8..b8233505bf9f 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1117,7 +1117,9 @@ static bool ieee80211_tx_prep_agg(struct ieee80211_tx_data *tx, queued = true; info->control.vif = &tx->sdata->vif; info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING; - info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS; + info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS | + IEEE80211_TX_CTL_NO_PS_BUFFER | + IEEE80211_TX_STATUS_EOSP; __skb_queue_tail(&tid_tx->pending, skb); if (skb_queue_len(&tid_tx->pending) > STA_MAX_TX_BUFFER) purge_skb = __skb_dequeue(&tid_tx->pending); From 541b6ed7cee1ec7c8f525f51a0ff097776111aeb Mon Sep 17 00:00:00 2001 From: Chaitanya T K Date: Wed, 10 Jun 2015 19:12:31 +0530 Subject: [PATCH 3/8] mac80211: wowlan: enable powersave if suspend while ps-polling If for any reason we're in the middle of PS-polling or awake after TX due to dynamic powersave while going to suspend, go back to save power. This might cause a response frame to get lost, but since we can't really wait for it while going to suspend that's still better than not enabling powersave which would cause higher power usage during (and possibly even after) suspend. Note that this really only affects the very few drivers that use the powersave implementation in mac80211. Signed-off-by: Chaitanya T K [rewrite misleading commit log] Signed-off-by: Johannes Berg --- net/mac80211/pm.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c index 06b60980c62c..b676b9fa707b 100644 --- a/net/mac80211/pm.c +++ b/net/mac80211/pm.c @@ -76,6 +76,22 @@ int __ieee80211_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan) if (sdata->vif.type != NL80211_IFTYPE_STATION) continue; ieee80211_mgd_quiesce(sdata); + /* If suspended during TX in progress, and wowlan + * is enabled (connection will be active) there + * can be a race where the driver is put out + * of power-save due to TX and during suspend + * dynamic_ps_timer is cancelled and TX packet + * is flushed, leaving the driver in ACTIVE even + * after resuming until dynamic_ps_timer puts + * driver back in DOZE. + */ + if (sdata->u.mgd.associated && + sdata->u.mgd.powersave && + !(local->hw.conf.flags & IEEE80211_CONF_PS)) { + local->hw.conf.flags |= IEEE80211_CONF_PS; + ieee80211_hw_config(local, + IEEE80211_CONF_CHANGE_PS); + } } err = drv_suspend(local, wowlan); From d8d9008cfb919db48d95f96b05e81f84b3774318 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 8 Jul 2015 15:41:50 +0300 Subject: [PATCH 4/8] mac80211: shut down interfaces before destroying interface list If the hardware is unregistered while interfaces are up, mac80211 will unregister all interfaces, which in turns causes mac80211 to be called again to remove them all from the driver and eventually shut down the hardware. During this shutdown, however, it's currently already unsafe to iterate the list of interfaces atomically, as the list is manipulated in an unsafe manner. This puts an undue burden on the driver - it must stop all its activities before calling ieee80211_unregister_hw(), while in the normal stop path it can do all cleanup in the stop method. If, for example, it's using the iteration during RX for some reason, it would have to stop RX before unregistering to avoid crashes. Fix this problem by closing all interfaces before unregistering them. This will cause the driver stop to have completed before we manipulate the interface list, and after the driver is stopped *and* has called ieee80211_unregister_hw() it really musn't be iterating any more as the memory will be freed as well. Signed-off-by: Johannes Berg --- net/mac80211/iface.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index ed1edac14372..553ac6dd4867 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -1863,10 +1863,6 @@ void ieee80211_sdata_stop(struct ieee80211_sub_if_data *sdata) ieee80211_teardown_sdata(sdata); } -/* - * Remove all interfaces, may only be called at hardware unregistration - * time because it doesn't do RCU-safe list removals. - */ void ieee80211_remove_interfaces(struct ieee80211_local *local) { struct ieee80211_sub_if_data *sdata, *tmp; @@ -1875,14 +1871,21 @@ void ieee80211_remove_interfaces(struct ieee80211_local *local) ASSERT_RTNL(); - /* - * Close all AP_VLAN interfaces first, as otherwise they - * might be closed while the AP interface they belong to - * is closed, causing unregister_netdevice_many() to crash. + /* Before destroying the interfaces, make sure they're all stopped so + * that the hardware is stopped. Otherwise, the driver might still be + * iterating the interfaces during the shutdown, e.g. from a worker + * or from RX processing or similar, and if it does so (using atomic + * iteration) while we're manipulating the list, the iteration will + * crash. + * + * After this, the hardware should be stopped and the driver should + * have stopped all of its activities, so that we can do RCU-unaware + * manipulations of the interface list below. */ - list_for_each_entry(sdata, &local->interfaces, list) - if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) - dev_close(sdata->dev); + cfg80211_shutdown_all_interfaces(local->hw.wiphy); + + WARN(local->open_count, "%s: open count remains %d\n", + wiphy_name(local->hw.wiphy), local->open_count); mutex_lock(&local->iflist_mtx); list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) { From 042ab5fc7a80b934032fcc673a125feb36645b33 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Thu, 9 Jul 2015 15:35:15 +0200 Subject: [PATCH 5/8] wireless: regulatory: reduce log level of CRDA related messages With a basic Linux userspace, the messages "Calling CRDA to update world regulatory domain" appears 10 times after boot every second or so, followed by a final "Exceeded CRDA call max attempts. Not calling CRDA". For those of us not having the corresponding userspace parts, having those messages repeatedly displayed at boot time is a bit annoying, so this commit reduces their log level to pr_debug(). Signed-off-by: Thomas Petazzoni Signed-off-by: Johannes Berg --- net/wireless/reg.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/net/wireless/reg.c b/net/wireless/reg.c index d359e0610198..29134c81e73c 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -544,15 +544,15 @@ static int call_crda(const char *alpha2) reg_regdb_query(alpha2); if (reg_crda_timeouts > REG_MAX_CRDA_TIMEOUTS) { - pr_info("Exceeded CRDA call max attempts. Not calling CRDA\n"); + pr_debug("Exceeded CRDA call max attempts. Not calling CRDA\n"); return -EINVAL; } if (!is_world_regdom((char *) alpha2)) - pr_info("Calling CRDA for country: %c%c\n", + pr_debug("Calling CRDA for country: %c%c\n", alpha2[0], alpha2[1]); else - pr_info("Calling CRDA to update world regulatory domain\n"); + pr_debug("Calling CRDA to update world regulatory domain\n"); return kobject_uevent_env(®_pdev->dev.kobj, KOBJ_CHANGE, env); } From 2ea752cd2ce066c5d8c1807b5310ef329885cecb Mon Sep 17 00:00:00 2001 From: Bob Copeland Date: Tue, 14 Jul 2015 08:31:55 -0400 Subject: [PATCH 6/8] mac80211: correct aid location in peering frames According to 802.11-2012 8.5.16.3.2 AID comes directly after the capability bytes in mesh peering confirm frames. The existing code, however, was adding a 2 byte offset to this location, resulting in garbage data going out over the air. Remove the offset to fix it. Signed-off-by: Bob Copeland Signed-off-by: Johannes Berg --- net/mac80211/mesh_plink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 5438d13e2f00..f17127e754c9 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -306,7 +306,7 @@ static int mesh_plink_frame_tx(struct ieee80211_sub_if_data *sdata, if (action == WLAN_SP_MESH_PEERING_CONFIRM) { /* AID */ pos = skb_put(skb, 2); - put_unaligned_le16(plid, pos + 2); + put_unaligned_le16(plid, pos); } if (ieee80211_add_srates_ie(sdata, skb, true, band) || ieee80211_add_ext_srates_ie(sdata, skb, true, band) || From b3e7de873df77c1fa0bc2cfaf3eaff757b80e773 Mon Sep 17 00:00:00 2001 From: Bob Copeland Date: Tue, 14 Jul 2015 08:31:56 -0400 Subject: [PATCH 7/8] mac80211: add missing length check for confirm frames Although mesh_rx_plink_frame() already checks that frames have enough bytes for the action code plus another two bytes for capability/reason code, it doesn't take into account that confirm frames also have an additional two-byte aid. As a result, a corrupt frame could cause a subsequent subtraction to wrap around to ill effect. Add another check for this case. Signed-off-by: Bob Copeland Signed-off-by: Johannes Berg --- net/mac80211/mesh_plink.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index f17127e754c9..3b59099413fb 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -1122,6 +1122,9 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, WLAN_SP_MESH_PEERING_CONFIRM) { baseaddr += 4; baselen += 4; + + if (baselen > len) + return; } ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems); mesh_process_plink_frame(sdata, mgmt, &elems); From 923b352f19d9ea971ae2536eab55f5fc9e95fedf Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Wed, 8 Jul 2015 15:41:44 +0300 Subject: [PATCH 8/8] cfg80211: use RTNL locked reg_can_beacon for IR-relaxation The RTNL is required to check for IR-relaxation conditions that allow more channels to beacon. Export an RTNL locked version of reg_can_beacon and use it where possible in AP/STA interface type flows, where IR-relaxation may be applicable. Fixes: 06f207fc5418 ("cfg80211: change GO_CONCURRENT to IR_CONCURRENT for STA") Signed-off-by: Arik Nemtsov Signed-off-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 17 ++++++++++++++++ net/mac80211/tdls.c | 6 +++--- net/wireless/chan.c | 45 +++++++++++++++++++++++++++++++----------- net/wireless/nl80211.c | 14 +++++++------ net/wireless/reg.c | 2 +- net/wireless/trace.h | 11 +++++++---- 6 files changed, 70 insertions(+), 25 deletions(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index a741678f24a2..883fe1e7c5a1 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -4868,6 +4868,23 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy, struct cfg80211_chan_def *chandef, enum nl80211_iftype iftype); +/** + * cfg80211_reg_can_beacon_relax - check if beaconing is allowed with relaxation + * @wiphy: the wiphy + * @chandef: the channel definition + * @iftype: interface type + * + * Return: %true if there is no secondary channel or the secondary channel(s) + * can be used for beaconing (i.e. is not a radar channel etc.). This version + * also checks if IR-relaxation conditions apply, to allow beaconing under + * more permissive conditions. + * + * Requires the RTNL to be held. + */ +bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + enum nl80211_iftype iftype); + /* * cfg80211_ch_switch_notify - update wdev channel and notify userspace * @dev: the device which switched channels diff --git a/net/mac80211/tdls.c b/net/mac80211/tdls.c index ad31b2dab4f5..8db6e2994bbc 100644 --- a/net/mac80211/tdls.c +++ b/net/mac80211/tdls.c @@ -60,6 +60,7 @@ ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata, struct ieee80211_channel *ch; struct cfg80211_chan_def chandef; int i, subband_start; + struct wiphy *wiphy = sdata->local->hw.wiphy; for (i = start; i <= end; i += spacing) { if (!ch_cnt) @@ -70,9 +71,8 @@ ieee80211_tdls_add_subband(struct ieee80211_sub_if_data *sdata, /* we will be active on the channel */ cfg80211_chandef_create(&chandef, ch, NL80211_CHAN_NO_HT); - if (cfg80211_reg_can_beacon(sdata->local->hw.wiphy, - &chandef, - sdata->wdev.iftype)) { + if (cfg80211_reg_can_beacon_relax(wiphy, &chandef, + sdata->wdev.iftype)) { ch_cnt++; /* * check if the next channel is also part of diff --git a/net/wireless/chan.c b/net/wireless/chan.c index 915b328b9ac5..59cabc9bce69 100644 --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -797,23 +797,18 @@ static bool cfg80211_ir_permissive_chan(struct wiphy *wiphy, return false; } -bool cfg80211_reg_can_beacon(struct wiphy *wiphy, - struct cfg80211_chan_def *chandef, - enum nl80211_iftype iftype) +static bool _cfg80211_reg_can_beacon(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + enum nl80211_iftype iftype, + bool check_no_ir) { bool res; u32 prohibited_flags = IEEE80211_CHAN_DISABLED | IEEE80211_CHAN_RADAR; - trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype); + trace_cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir); - /* - * Under certain conditions suggested by some regulatory bodies a - * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag - * only if such relaxations are not enabled and the conditions are not - * met. - */ - if (!cfg80211_ir_permissive_chan(wiphy, iftype, chandef->chan)) + if (check_no_ir) prohibited_flags |= IEEE80211_CHAN_NO_IR; if (cfg80211_chandef_dfs_required(wiphy, chandef, iftype) > 0 && @@ -827,8 +822,36 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy, trace_cfg80211_return_bool(res); return res; } + +bool cfg80211_reg_can_beacon(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + enum nl80211_iftype iftype) +{ + return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, true); +} EXPORT_SYMBOL(cfg80211_reg_can_beacon); +bool cfg80211_reg_can_beacon_relax(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + enum nl80211_iftype iftype) +{ + bool check_no_ir; + + ASSERT_RTNL(); + + /* + * Under certain conditions suggested by some regulatory bodies a + * GO/STA can IR on channels marked with IEEE80211_NO_IR. Set this flag + * only if such relaxations are not enabled and the conditions are not + * met. + */ + check_no_ir = !cfg80211_ir_permissive_chan(wiphy, iftype, + chandef->chan); + + return _cfg80211_reg_can_beacon(wiphy, chandef, iftype, check_no_ir); +} +EXPORT_SYMBOL(cfg80211_reg_can_beacon_relax); + int cfg80211_set_monitor_channel(struct cfg80211_registered_device *rdev, struct cfg80211_chan_def *chandef) { diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index c264effd00a6..76b41578a838 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2003,7 +2003,8 @@ static int __nl80211_set_channel(struct cfg80211_registered_device *rdev, switch (iftype) { case NL80211_IFTYPE_AP: case NL80211_IFTYPE_P2P_GO: - if (!cfg80211_reg_can_beacon(&rdev->wiphy, &chandef, iftype)) { + if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, &chandef, + iftype)) { result = -EINVAL; break; } @@ -3403,8 +3404,8 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info) } else if (!nl80211_get_ap_channel(rdev, ¶ms)) return -EINVAL; - if (!cfg80211_reg_can_beacon(&rdev->wiphy, ¶ms.chandef, - wdev->iftype)) + if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, ¶ms.chandef, + wdev->iftype)) return -EINVAL; if (info->attrs[NL80211_ATTR_ACL_POLICY]) { @@ -6492,8 +6493,8 @@ skip_beacons: if (err) return err; - if (!cfg80211_reg_can_beacon(&rdev->wiphy, ¶ms.chandef, - wdev->iftype)) + if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, ¶ms.chandef, + wdev->iftype)) return -EINVAL; err = cfg80211_chandef_dfs_required(wdev->wiphy, @@ -10170,7 +10171,8 @@ static int nl80211_tdls_channel_switch(struct sk_buff *skb, return -EINVAL; /* we will be active on the TDLS link */ - if (!cfg80211_reg_can_beacon(&rdev->wiphy, &chandef, wdev->iftype)) + if (!cfg80211_reg_can_beacon_relax(&rdev->wiphy, &chandef, + wdev->iftype)) return -EINVAL; /* don't allow switching to DFS channels */ diff --git a/net/wireless/reg.c b/net/wireless/reg.c index 29134c81e73c..aa2d75482017 100644 --- a/net/wireless/reg.c +++ b/net/wireless/reg.c @@ -1589,7 +1589,7 @@ static bool reg_wdev_chan_valid(struct wiphy *wiphy, struct wireless_dev *wdev) case NL80211_IFTYPE_AP: case NL80211_IFTYPE_P2P_GO: case NL80211_IFTYPE_ADHOC: - return cfg80211_reg_can_beacon(wiphy, &chandef, iftype); + return cfg80211_reg_can_beacon_relax(wiphy, &chandef, iftype); case NL80211_IFTYPE_STATION: case NL80211_IFTYPE_P2P_CLIENT: return cfg80211_chandef_usable(wiphy, &chandef, diff --git a/net/wireless/trace.h b/net/wireless/trace.h index af3617c9879e..a808279a432a 100644 --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -2358,20 +2358,23 @@ TRACE_EVENT(cfg80211_cqm_rssi_notify, TRACE_EVENT(cfg80211_reg_can_beacon, TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef, - enum nl80211_iftype iftype), - TP_ARGS(wiphy, chandef, iftype), + enum nl80211_iftype iftype, bool check_no_ir), + TP_ARGS(wiphy, chandef, iftype, check_no_ir), TP_STRUCT__entry( WIPHY_ENTRY CHAN_DEF_ENTRY __field(enum nl80211_iftype, iftype) + __field(bool, check_no_ir) ), TP_fast_assign( WIPHY_ASSIGN; CHAN_DEF_ASSIGN(chandef); __entry->iftype = iftype; + __entry->check_no_ir = check_no_ir; ), - TP_printk(WIPHY_PR_FMT ", " CHAN_DEF_PR_FMT ", iftype=%d", - WIPHY_PR_ARG, CHAN_DEF_PR_ARG, __entry->iftype) + TP_printk(WIPHY_PR_FMT ", " CHAN_DEF_PR_FMT ", iftype=%d check_no_ir=%s", + WIPHY_PR_ARG, CHAN_DEF_PR_ARG, __entry->iftype, + BOOL_TO_STR(__entry->check_no_ir)) ); TRACE_EVENT(cfg80211_chandef_dfs_required,