From ba23d2068d85f6616ea5f92320c04e87d4b9e141 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 27 Dec 2012 17:32:09 +0100 Subject: [PATCH] cfg80211: disallow more station changes The following changes are invalid and should be disallowed when a station already exists: * supported rates changes, except for TDLS peers * listen interval changes * HT capability changes Disallow them and also update a mac80211 comment explaining how they would be racy. Signed-off-by: Johannes Berg --- net/mac80211/cfg.c | 9 +++++---- net/wireless/nl80211.c | 22 ++++++++-------------- 2 files changed, 13 insertions(+), 18 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index f4d12c7..7d290bc 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1208,10 +1208,11 @@ static int sta_apply_parameters(struct ieee80211_local *local, sta->sta.aid = params->aid; /* - * FIXME: updating the following information is racy when this - * function is called from ieee80211_change_station(). - * However, all this information should be static so - * maybe we should just reject attemps to change it. + * Some of the following updates would be racy if called on an + * existing station, via ieee80211_change_station(). However, + * all such changes are rejected by cfg80211 except for updates + * changing the supported rates on an existing but not yet used + * TDLS peer. */ if (params->listen_interval >= 0) diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 087f68b..9bd8340 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -3188,13 +3188,9 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info) nla_len(info->attrs[NL80211_ATTR_STA_SUPPORTED_RATES]); } - if (info->attrs[NL80211_ATTR_STA_LISTEN_INTERVAL]) - params.listen_interval = - nla_get_u16(info->attrs[NL80211_ATTR_STA_LISTEN_INTERVAL]); - - if (info->attrs[NL80211_ATTR_HT_CAPABILITY]) - params.ht_capa = - nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY]); + if (info->attrs[NL80211_ATTR_STA_LISTEN_INTERVAL] || + info->attrs[NL80211_ATTR_HT_CAPABILITY]) + return -EINVAL; if (!rdev->ops->change_station) return -EOPNOTSUPP; @@ -3246,6 +3242,10 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info) BIT(NL80211_STA_FLAG_ASSOCIATED))) return -EINVAL; + /* reject other things that can't change */ + if (params.supported_rates) + return -EINVAL; + /* must be last in here for error handling */ params.vlan = get_vlan(info, rdev); if (IS_ERR(params.vlan)) @@ -3265,10 +3265,6 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info) /* disallow things sta doesn't support */ if (params.plink_action) return -EINVAL; - if (params.ht_capa) - return -EINVAL; - if (params.listen_interval >= 0) - return -EINVAL; /* reject any changes other than AUTHORIZED */ if (params.sta_flags_mask & ~BIT(NL80211_STA_FLAG_AUTHORIZED)) return -EINVAL; @@ -3277,9 +3273,7 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info) /* disallow things mesh doesn't support */ if (params.vlan) return -EINVAL; - if (params.ht_capa) - return -EINVAL; - if (params.listen_interval >= 0) + if (params.supported_rates) return -EINVAL; /* * No special handling for TDLS here -- the userspace -- 2.7.4