mac80211: use correct station flags lock

This code is modifying the station flags, and
as such should hold the flags lock so it can
do so atomically vs. other flags modifications
and readers. This issue was introduced when
this code was added in eccb8e8f, as it used
the wrong lock (thus not fixing the race that
was previously documented in a comment.)

Cc: stable@kernel.org [2.6.31+]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 5de1ca3..171e8ff 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -577,6 +577,7 @@ static void sta_apply_parameters(struct ieee80211_local *local,
                                 struct sta_info *sta,
                                 struct station_parameters *params)
 {
+       unsigned long flags;
        u32 rates;
        int i, j;
        struct ieee80211_supported_band *sband;
@@ -585,7 +586,7 @@ static void sta_apply_parameters(struct ieee80211_local *local,
 
        sband = local->hw.wiphy->bands[local->oper_channel->band];
 
-       spin_lock_bh(&sta->lock);
+       spin_lock_irqsave(&sta->flaglock, flags);
        mask = params->sta_flags_mask;
        set = params->sta_flags_set;
 
@@ -612,7 +613,7 @@ static void sta_apply_parameters(struct ieee80211_local *local,
                if (set & BIT(NL80211_STA_FLAG_MFP))
                        sta->flags |= WLAN_STA_MFP;
        }
-       spin_unlock_bh(&sta->lock);
+       spin_unlock_irqrestore(&sta->flaglock, flags);
 
        /*
         * cfg80211 validates this (1-2007) and allows setting the AID