mac80211: fix nested sdata lock for IBSS/CSA

This fixes a regression introduced by my patch "mac80211: don't cancel
csa finalize work within stop_ap", which added sdata locks to
ieee80211_csa_finalize_work() without removing the locking for
ieee80211_ibss_finish_csa(), which is called by the former, resulting
in a deadlock due to nested locking.

Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 0f1fb5db4bdb6f557007d7883dced071c2032aa8..df21e4f79df86f299a759de415e197d7c317a513 100644 (file)
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -534,7 +534,8 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
        int err;
        u16 capability;
 
-       sdata_lock(sdata);
+       sdata_assert_lock(sdata);
+
        /* update cfg80211 bss information with the new channel */
        if (!is_zero_ether_addr(ifibss->bssid)) {
                capability = WLAN_CAPABILITY_IBSS;
@@ -559,7 +560,6 @@ int ieee80211_ibss_finish_csa(struct ieee80211_sub_if_data *sdata)
 
        /* generate the beacon */
        err = ieee80211_ibss_csa_beacon(sdata, NULL);
-       sdata_unlock(sdata);
        if (err < 0)
                return err;