mac80211: fix SMPS debugfs locking

commit 243e6df4ed919880d079d717641ad699c6530a03 upstream.

The locking with SMPS requests means that the
debugs file should lock the mgd mutex, not the
iflist mutex. Calls to __ieee80211_request_smps()
need to hold that mutex, so add an assertion.

This has always been wrong, but for some reason
never been noticed, probably because the locking
error only happens while unassociated.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 9cd73b11506e85b1a0d5ecf26563da8d1d439d18..40f7357c26998870302079edf9bc0c7e0ab23d49 100644 (file)
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1471,6 +1471,8 @@ int __ieee80211_request_smps(struct ieee80211_sub_if_data *sdata,
        enum ieee80211_smps_mode old_req;
        int err;
 
+       lockdep_assert_held(&sdata->u.mgd.mtx);
+
        old_req = sdata->u.mgd.req_smps;
        sdata->u.mgd.req_smps = smps_mode;
 

diff --git a/net/mac80211/debugfs_netdev.c b/net/mac80211/debugfs_netdev.c
index 2dabdf7680d0659a45d60e1aafa8536ef8e711bc..bae23ad4d8a34dde063b62facdd5ebbdc12e55cf 100644 (file)
--- a/net/mac80211/debugfs_netdev.c
+++ b/net/mac80211/debugfs_netdev.c
@@ -172,9 +172,9 @@ static int ieee80211_set_smps(struct ieee80211_sub_if_data *sdata,
        if (sdata->vif.type != NL80211_IFTYPE_STATION)
                return -EOPNOTSUPP;
 
-       mutex_lock(&local->iflist_mtx);
+       mutex_lock(&sdata->u.mgd.mtx);
        err = __ieee80211_request_smps(sdata, smps_mode);
-       mutex_unlock(&local->iflist_mtx);
+       mutex_unlock(&sdata->u.mgd.mtx);
 
        return err;
 }