From 83d5cc012441531ab0bf6f99881958e964e9cf11 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 12 Jan 2012 09:31:10 +0100 Subject: mac80211: station state transition error handling In the future, when we start notifying drivers, state transitions could potentially fail. To make it easier to distinguish between programming bugs and driver failures: * rename sta_info_move_state() to sta_info_pre_move_state() which can only be called before the station is inserted (and check this with a new station flag). * rename sta_info_move_state_checked() to just plain sta_info_move_state(), as it will be the regular function that can fail for more than just one reason (bad transition or an error from the driver) This makes the programming model easier -- one of the functions can only be called before insertion and can't fail, the other can fail. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/mesh_plink.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'net/mac80211/mesh_plink.c') diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 41ef1b47644..bf92e2878fe 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -96,9 +96,9 @@ static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata, if (!sta) return NULL; - sta_info_move_state(sta, IEEE80211_STA_AUTH); - sta_info_move_state(sta, IEEE80211_STA_ASSOC); - sta_info_move_state(sta, IEEE80211_STA_AUTHORIZED); + sta_info_pre_move_state(sta, IEEE80211_STA_AUTH); + sta_info_pre_move_state(sta, IEEE80211_STA_ASSOC); + sta_info_pre_move_state(sta, IEEE80211_STA_AUTHORIZED); set_sta_flag(sta, WLAN_STA_WME); -- cgit v1.2.3-70-g09d2 From 5533513784a88049e19dd2ab380a452b61e5171e Mon Sep 17 00:00:00 2001 From: Ashok Nagarajan Date: Tue, 28 Feb 2012 17:04:08 -0800 Subject: {nl,cfg,mac}80211: Implement RSSI threshold for mesh peering Mesh peer links are established only if average rssi of the peer candidate satisfies the threshold. This is not in 802.11s specification but was requested by David Fulgham, an open80211s user. This is a way to avoid marginal peer links with stations that are barely within range. This patch adds a new mesh configuration parameter, mesh_rssi_threshold. This feature is supported only for hardwares that report signal in dBm. Signed-off-by: Ashok Nagarajan Signed-off-by: Javier Cardona Signed-off-by: John W. Linville --- include/linux/nl80211.h | 5 +++++ include/net/cfg80211.h | 1 + net/mac80211/cfg.c | 8 ++++++++ net/mac80211/debugfs_netdev.c | 2 ++ net/mac80211/mesh_plink.c | 16 +++++++++++++++- net/wireless/mesh.c | 3 +++ net/wireless/nl80211.c | 5 +++++ 7 files changed, 39 insertions(+), 1 deletion(-) (limited to 'net/mac80211/mesh_plink.c') diff --git a/include/linux/nl80211.h b/include/linux/nl80211.h index be35a68746a..38fda5ee57f 100644 --- a/include/linux/nl80211.h +++ b/include/linux/nl80211.h @@ -2112,6 +2112,10 @@ enum nl80211_mntr_flags { * @NL80211_MESHCONF_FORWARDING: set Mesh STA as forwarding or non-forwarding * or forwarding entity (default is TRUE - forwarding entity) * + * @NL80211_MESHCONF_RSSI_THRESHOLD: RSSI threshold in dBm. This specifies the + * threshold for average signal strength of candidate station to establish + * a peer link. + * * @NL80211_MESHCONF_ATTR_MAX: highest possible mesh configuration attribute * * @__NL80211_MESHCONF_ATTR_AFTER_LAST: internal use @@ -2137,6 +2141,7 @@ enum nl80211_meshconf_params { NL80211_MESHCONF_GATE_ANNOUNCEMENTS, NL80211_MESHCONF_HWMP_PERR_MIN_INTERVAL, NL80211_MESHCONF_FORWARDING, + NL80211_MESHCONF_RSSI_THRESHOLD, /* keep last */ __NL80211_MESHCONF_ATTR_AFTER_LAST, diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 0178c748937..b4e015c9088 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -809,6 +809,7 @@ struct mesh_config { * Still keeping the same nomenclature to be in sync with the spec. */ bool dot11MeshGateAnnouncementProtocol; bool dot11MeshForwarding; + s32 rssi_threshold; }; /** diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 6a77d4c910f..ab31cc56a2f 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1314,6 +1314,14 @@ static int ieee80211_update_mesh_config(struct wiphy *wiphy, } if (_chg_mesh_attr(NL80211_MESHCONF_FORWARDING, mask)) conf->dot11MeshForwarding = nconf->dot11MeshForwarding; + if (_chg_mesh_attr(NL80211_MESHCONF_RSSI_THRESHOLD, mask)) { + /* our RSSI threshold implementation is supported only for + * devices that report signal in dBm. + */ + if (!(sdata->local->hw.flags & IEEE80211_HW_SIGNAL_DBM)) + return -ENOTSUPP; + conf->rssi_threshold = nconf->rssi_threshold; + } return 0; } diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c index 510ed1dab3c..9f484d8905f 100644 --- a/net/mac80211/debugfs_netdev.c +++ b/net/mac80211/debugfs_netdev.c @@ -443,6 +443,7 @@ IEEE80211_IF_FILE(dot11MeshGateAnnouncementProtocol, IEEE80211_IF_FILE(dot11MeshHWMPRannInterval, u.mesh.mshcfg.dot11MeshHWMPRannInterval, DEC); IEEE80211_IF_FILE(dot11MeshForwarding, u.mesh.mshcfg.dot11MeshForwarding, DEC); +IEEE80211_IF_FILE(rssi_threshold, u.mesh.mshcfg.rssi_threshold, DEC); #endif @@ -581,6 +582,7 @@ static void add_mesh_config(struct ieee80211_sub_if_data *sdata) MESHPARAMS_ADD(dot11MeshHWMPRootMode); MESHPARAMS_ADD(dot11MeshHWMPRannInterval); MESHPARAMS_ADD(dot11MeshGateAnnouncementProtocol); + MESHPARAMS_ADD(rssi_threshold); #undef MESHPARAMS_ADD } #endif diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 8806e5ef8ff..80ce5277253 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -31,6 +31,11 @@ #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout) #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks) +#define sta_meets_rssi_threshold(sta, sdata) \ + (sdata->u.mesh.mshcfg.rssi_threshold == 0 ||\ + (s8) -ewma_read(&sta->avg_signal) > \ + sdata->u.mesh.mshcfg.rssi_threshold) + enum plink_event { PLINK_UNDEFINED, OPN_ACPT, @@ -301,7 +306,8 @@ void mesh_neighbour_update(u8 *hw_addr, u32 rates, if (mesh_peer_accepts_plinks(elems) && sta->plink_state == NL80211_PLINK_LISTEN && sdata->u.mesh.accepting_plinks && - sdata->u.mesh.mshcfg.auto_open_plinks) + sdata->u.mesh.mshcfg.auto_open_plinks && + sta_meets_rssi_threshold(sta, sdata)) mesh_plink_open(sta); rcu_read_unlock(); @@ -531,6 +537,14 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m return; } + if (ftype == WLAN_SP_MESH_PEERING_OPEN && + !sta_meets_rssi_threshold(sta, sdata)) { + mpl_dbg("Mesh plink: %pM does not meet rssi threshold\n", + sta->sta.addr); + rcu_read_unlock(); + return; + } + if (sta && !test_sta_flag(sta, WLAN_STA_AUTH)) { mpl_dbg("Mesh plink: Action frame from non-authed peer\n"); rcu_read_unlock(); diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c index 9d3e3b6bfcf..ba21ab22187 100644 --- a/net/wireless/mesh.c +++ b/net/wireless/mesh.c @@ -23,6 +23,8 @@ #define MESH_PERR_MIN_INT 100 #define MESH_DIAM_TRAVERSAL_TIME 50 +#define MESH_RSSI_THRESHOLD 0 + /* * A path will be refreshed if it is used PATH_REFRESH_TIME milliseconds * before timing out. This way it will remain ACTIVE and no data frames @@ -56,6 +58,7 @@ const struct mesh_config default_mesh_config = { .dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL, .dot11MeshGateAnnouncementProtocol = false, .dot11MeshForwarding = true, + .rssi_threshold = MESH_RSSI_THRESHOLD, }; const struct mesh_setup default_mesh_setup = { diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 1998c368277..25a470abd21 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3290,6 +3290,8 @@ static int nl80211_get_mesh_config(struct sk_buff *skb, cur_params.dot11MeshGateAnnouncementProtocol); NLA_PUT_U8(msg, NL80211_MESHCONF_FORWARDING, cur_params.dot11MeshForwarding); + NLA_PUT_U32(msg, NL80211_MESHCONF_RSSI_THRESHOLD, + cur_params.rssi_threshold); nla_nest_end(msg, pinfoattr); genlmsg_end(msg, hdr); return genlmsg_reply(msg, info); @@ -3322,6 +3324,7 @@ static const struct nla_policy nl80211_meshconf_params_policy[NL80211_MESHCONF_A [NL80211_MESHCONF_HWMP_RANN_INTERVAL] = { .type = NLA_U16 }, [NL80211_MESHCONF_GATE_ANNOUNCEMENTS] = { .type = NLA_U8 }, [NL80211_MESHCONF_FORWARDING] = { .type = NLA_U8 }, + [NL80211_MESHCONF_RSSI_THRESHOLD] = { .type = NLA_U32}, }; static const struct nla_policy @@ -3413,6 +3416,8 @@ do {\ nla_get_u8); FILL_IN_MESH_PARAM_IF_SET(tb, cfg, dot11MeshForwarding, mask, NL80211_MESHCONF_FORWARDING, nla_get_u8); + FILL_IN_MESH_PARAM_IF_SET(tb, cfg, rssi_threshold, + mask, NL80211_MESHCONF_RSSI_THRESHOLD, nla_get_u32); if (mask_out) *mask_out = mask; -- cgit v1.2.3-70-g09d2 From 3d4f96997263d97cd4d60373f1ed8184ee6df31b Mon Sep 17 00:00:00 2001 From: Ashok Nagarajan Date: Tue, 6 Mar 2012 12:48:30 -0800 Subject: mac80211: Fix potential null pointer dereferencing The patch "{nl,cfg,mac}80211: Implement RSSI threshold for mesh peering" has a potential null pointer dereferencing problem. Thanks to Dan Carpenter for pointing out. This patch will fix the issue. Signed-off-by: Ashok Nagarajan Signed-off-by: John W. Linville --- net/mac80211/mesh_plink.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'net/mac80211/mesh_plink.c') diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 80ce5277253..4e53c4cbca9 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -31,10 +31,11 @@ #define dot11MeshHoldingTimeout(s) (s->u.mesh.mshcfg.dot11MeshHoldingTimeout) #define dot11MeshMaxPeerLinks(s) (s->u.mesh.mshcfg.dot11MeshMaxPeerLinks) -#define sta_meets_rssi_threshold(sta, sdata) \ +/* We only need a valid sta if user configured a minimum rssi_threshold. */ +#define rssi_threshold_check(sta, sdata) \ (sdata->u.mesh.mshcfg.rssi_threshold == 0 ||\ - (s8) -ewma_read(&sta->avg_signal) > \ - sdata->u.mesh.mshcfg.rssi_threshold) + (sta && (s8) -ewma_read(&sta->avg_signal) > \ + sdata->u.mesh.mshcfg.rssi_threshold)) enum plink_event { PLINK_UNDEFINED, @@ -307,7 +308,7 @@ void mesh_neighbour_update(u8 *hw_addr, u32 rates, sta->plink_state == NL80211_PLINK_LISTEN && sdata->u.mesh.accepting_plinks && sdata->u.mesh.mshcfg.auto_open_plinks && - sta_meets_rssi_threshold(sta, sdata)) + rssi_threshold_check(sta, sdata)) mesh_plink_open(sta); rcu_read_unlock(); @@ -538,9 +539,9 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m } if (ftype == WLAN_SP_MESH_PEERING_OPEN && - !sta_meets_rssi_threshold(sta, sdata)) { + !rssi_threshold_check(sta, sdata)) { mpl_dbg("Mesh plink: %pM does not meet rssi threshold\n", - sta->sta.addr); + mgmt->sa); rcu_read_unlock(); return; } -- cgit v1.2.3-70-g09d2