From 31a60ed1e95ab8afbadb65599bef12b195080a0c Mon Sep 17 00:00:00 2001 From: Jukka Rissanen Date: Mon, 15 Dec 2014 13:25:38 +0200 Subject: nl80211: Convert sched_scan_req pointer to RCU pointer Because of possible races when accessing sched_scan_req pointer in rdev, the sched_scan_req is converted to RCU pointer. Signed-off-by: Jukka Rissanen Signed-off-by: Johannes Berg --- net/wireless/core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) (limited to 'net/wireless/core.c') diff --git a/net/wireless/core.c b/net/wireless/core.c index b661fcce7e3c..0743449405ca 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -867,6 +867,7 @@ void __cfg80211_leave(struct cfg80211_registered_device *rdev, struct wireless_dev *wdev) { struct net_device *dev = wdev->netdev; + struct cfg80211_sched_scan_request *sched_scan_req; ASSERT_RTNL(); ASSERT_WDEV_LOCK(wdev); @@ -877,7 +878,8 @@ void __cfg80211_leave(struct cfg80211_registered_device *rdev, break; case NL80211_IFTYPE_P2P_CLIENT: case NL80211_IFTYPE_STATION: - if (rdev->sched_scan_req && dev == rdev->sched_scan_req->dev) + sched_scan_req = rtnl_dereference(rdev->sched_scan_req); + if (sched_scan_req && dev == sched_scan_req->dev) __cfg80211_stop_sched_scan(rdev, false); #ifdef CONFIG_CFG80211_WEXT @@ -956,6 +958,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, struct net_device *dev = netdev_notifier_info_to_dev(ptr); struct wireless_dev *wdev = dev->ieee80211_ptr; struct cfg80211_registered_device *rdev; + struct cfg80211_sched_scan_request *sched_scan_req; if (!wdev) return NOTIFY_DONE; @@ -1021,8 +1024,9 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, ___cfg80211_scan_done(rdev, false); } - if (WARN_ON(rdev->sched_scan_req && - rdev->sched_scan_req->dev == wdev->netdev)) { + sched_scan_req = rtnl_dereference(rdev->sched_scan_req); + if (WARN_ON(sched_scan_req && + sched_scan_req->dev == wdev->netdev)) { __cfg80211_stop_sched_scan(rdev, false); } -- cgit v1.2.3-59-g8ed1b