From 51b50fbeb574f581c0b112e035541f42fa3e604a Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Sun, 24 May 2009 16:42:30 +0200 Subject: [PATCH] cfg80211: validate AID of stations being added We have some validation code in mac80211 but said code will force an invalid AID to 0 which isn't a valid AID either; instead require a valid AID (1-2007) to be passed in from userspace in cfg80211 already. Also move the code before the race comment since it can only be executed during STA addition and thus is not racy. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/cfg.c | 13 +++++++------ net/wireless/nl80211.c | 4 ++++ 2 files changed, 11 insertions(+), 6 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 77e9ff5ec4f3..cdfdb2eaad9f 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -663,6 +663,13 @@ static void sta_apply_parameters(struct ieee80211_local *local, } spin_unlock_bh(&sta->lock); + /* + * cfg80211 validates this (1-2007) and allows setting the AID + * only when creating a new station entry + */ + if (params->aid) + sta->sta.aid = params->aid; + /* * FIXME: updating the following information is racy when this * function is called from ieee80211_change_station(). @@ -670,12 +677,6 @@ static void sta_apply_parameters(struct ieee80211_local *local, * maybe we should just reject attemps to change it. */ - if (params->aid) { - sta->sta.aid = params->aid; - if (sta->sta.aid > IEEE80211_MAX_AID) - sta->sta.aid = 0; /* XXX: should this be an error? */ - } - if (params->listen_interval >= 0) sta->listen_interval = params->listen_interval; diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 4b4d3c8a1aed..19dc796bb0b8 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -1738,7 +1738,11 @@ static int nl80211_new_station(struct sk_buff *skb, struct genl_info *info) nla_len(info->attrs[NL80211_ATTR_STA_SUPPORTED_RATES]); params.listen_interval = nla_get_u16(info->attrs[NL80211_ATTR_STA_LISTEN_INTERVAL]); + params.aid = nla_get_u16(info->attrs[NL80211_ATTR_STA_AID]); + if (!params.aid || params.aid > IEEE80211_MAX_AID) + return -EINVAL; + if (info->attrs[NL80211_ATTR_HT_CAPABILITY]) params.ht_capa = nla_data(info->attrs[NL80211_ATTR_HT_CAPABILITY]);