From: Johannes Berg Date: Tue, 19 Apr 2011 18:44:04 +0000 (+0200) Subject: mac80211: fix SMPS debugfs locking X-Git-Tag: v2.6.38.6~13 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6ee931e9812bdf3774cbd74571d2fdfba037aac9;p=thirdparty%2Fkernel%2Fstable.git 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 Signed-off-by: John W. Linville Signed-off-by: Greg Kroah-Hartman --- diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 9cd73b11506e8..40f7357c26998 100644 --- 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 2dabdf7680d06..bae23ad4d8a34 100644 --- 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; }