From 4b4b8229aeff4ca09b4aee921d383c596146eca0 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Fri, 13 Jul 2012 16:14:45 +0200 Subject: [PATCH] mac80211: fix use after free roc is destroyed then roc->started is referenced. Keep a local cache. Signed-off-by: Alan Cox Signed-off-by: Johannes Berg --- net/mac80211/offchannel.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c index 8c047fc8b325..635c3250c668 100644 --- a/net/mac80211/offchannel.c +++ b/net/mac80211/offchannel.c @@ -324,6 +324,7 @@ void ieee80211_sw_roc_work(struct work_struct *work) container_of(work, struct ieee80211_roc_work, work.work); struct ieee80211_sub_if_data *sdata = roc->sdata; struct ieee80211_local *local = sdata->local; + bool started; mutex_lock(&local->mtx); @@ -366,9 +367,10 @@ void ieee80211_sw_roc_work(struct work_struct *work) /* finish this ROC */ finish: list_del(&roc->list); + started = roc->started; ieee80211_roc_notify_destroy(roc); - if (roc->started) { + if (started) { drv_flush(local, false); local->tmp_channel = NULL; @@ -379,7 +381,7 @@ void ieee80211_sw_roc_work(struct work_struct *work) ieee80211_recalc_idle(local); - if (roc->started) + if (started) ieee80211_start_next_roc(local); }