From fab57a6cc227468ca9e6a4c7ff8d3b10727785ee Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 29 Jan 2014 13:28:02 +0100 Subject: [PATCH] mac80211: fix virtual monitor interface iteration During channel context assignment, the interface should be found by interface iteration, so we need to assign the pointer before the channel context. Reported-by: Emmanuel Grumbach Tested-by: Emmanuel Grumbach Signed-off-by: Johannes Berg --- net/mac80211/iface.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index ae2eb148a028..d6d1f1df9119 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -418,20 +418,24 @@ int ieee80211_add_virtual_monitor(struct ieee80211_local *local) return ret; } + mutex_lock(&local->iflist_mtx); + rcu_assign_pointer(local->monitor_sdata, sdata); + mutex_unlock(&local->iflist_mtx); + mutex_lock(&local->mtx); ret = ieee80211_vif_use_channel(sdata, &local->monitor_chandef, IEEE80211_CHANCTX_EXCLUSIVE); mutex_unlock(&local->mtx); if (ret) { + mutex_lock(&local->iflist_mtx); + rcu_assign_pointer(local->monitor_sdata, NULL); + mutex_unlock(&local->iflist_mtx); + synchronize_net(); drv_remove_interface(local, sdata); kfree(sdata); return ret; } - mutex_lock(&local->iflist_mtx); - rcu_assign_pointer(local->monitor_sdata, sdata); - mutex_unlock(&local->iflist_mtx); - return 0; }