From 5ffae43208ec160e584117fabee2cddc5ad0e39a Mon Sep 17 00:00:00 2001 From: Lior David Date: Mon, 22 Aug 2016 12:42:19 +0300 Subject: [PATCH] wil6210: fix protection of wil->scan_request Currently the places that check wil->scan_request and call cfg80211_scan_done are not consistently protected, so there is a risk that cfg80211_scan_done will be called with NULL scan_request, causing a kernel crash. Fix this by using p2p_wdev_mutex in few other places that access scan_request. This makes sense since scan_request may point to p2p_wdev, and it is not worth the extra complexity of adding a new mutex. Signed-off-by: Lior David Signed-off-by: Maya Erez Signed-off-by: Kalle Valo --- drivers/net/wireless/ath/wil6210/cfg80211.c | 3 +++ drivers/net/wireless/ath/wil6210/main.c | 4 ++++ drivers/net/wireless/ath/wil6210/wil6210.h | 2 +- drivers/net/wireless/ath/wil6210/wmi.c | 4 ++-- 4 files changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/wil6210/cfg80211.c b/drivers/net/wireless/ath/wil6210/cfg80211.c index ffacc76..d117240 100644 --- a/drivers/net/wireless/ath/wil6210/cfg80211.c +++ b/drivers/net/wireless/ath/wil6210/cfg80211.c @@ -354,10 +354,13 @@ static int wil_cfg80211_scan(struct wiphy *wiphy, wil_dbg_misc(wil, "%s(), wdev=0x%p iftype=%d\n", __func__, wdev, wdev->iftype); + mutex_lock(&wil->p2p_wdev_mutex); if (wil->scan_request) { wil_err(wil, "Already scanning\n"); + mutex_unlock(&wil->p2p_wdev_mutex); return -EAGAIN; } + mutex_unlock(&wil->p2p_wdev_mutex); /* check we are client side */ switch (wdev->iftype) { diff --git a/drivers/net/wireless/ath/wil6210/main.c b/drivers/net/wireless/ath/wil6210/main.c index d0b180c..7b7619c 100644 --- a/drivers/net/wireless/ath/wil6210/main.c +++ b/drivers/net/wireless/ath/wil6210/main.c @@ -852,6 +852,7 @@ int wil_reset(struct wil6210_priv *wil, bool load_fw) bitmap_zero(wil->status, wil_status_last); mutex_unlock(&wil->wmi_mutex); + mutex_lock(&wil->p2p_wdev_mutex); if (wil->scan_request) { struct cfg80211_scan_info info = { .aborted = true, @@ -863,6 +864,7 @@ int wil_reset(struct wil6210_priv *wil, bool load_fw) cfg80211_scan_done(wil->scan_request, &info); wil->scan_request = NULL; } + mutex_unlock(&wil->p2p_wdev_mutex); wil_mask_irq(wil); @@ -1055,6 +1057,7 @@ int __wil_down(struct wil6210_priv *wil) wil_p2p_stop_radio_operations(wil); + mutex_lock(&wil->p2p_wdev_mutex); if (wil->scan_request) { struct cfg80211_scan_info info = { .aborted = true, @@ -1066,6 +1069,7 @@ int __wil_down(struct wil6210_priv *wil) cfg80211_scan_done(wil->scan_request, &info); wil->scan_request = NULL; } + mutex_unlock(&wil->p2p_wdev_mutex); wil_reset(wil, false); diff --git a/drivers/net/wireless/ath/wil6210/wil6210.h b/drivers/net/wireless/ath/wil6210/wil6210.h index 6087691..1eb7fe7 100644 --- a/drivers/net/wireless/ath/wil6210/wil6210.h +++ b/drivers/net/wireless/ath/wil6210/wil6210.h @@ -657,7 +657,7 @@ struct wil6210_priv { /* P2P_DEVICE vif */ struct wireless_dev *p2p_wdev; - struct mutex p2p_wdev_mutex; /* protect @p2p_wdev */ + struct mutex p2p_wdev_mutex; /* protect @p2p_wdev and @scan_request */ struct wireless_dev *radio_wdev; /* High Access Latency Policy voting */ diff --git a/drivers/net/wireless/ath/wil6210/wmi.c b/drivers/net/wireless/ath/wil6210/wmi.c index 4d92541..0b109b2 100644 --- a/drivers/net/wireless/ath/wil6210/wmi.c +++ b/drivers/net/wireless/ath/wil6210/wmi.c @@ -424,6 +424,7 @@ static void wmi_evt_tx_mgmt(struct wil6210_priv *wil, int id, void *d, int len) static void wmi_evt_scan_complete(struct wil6210_priv *wil, int id, void *d, int len) { + mutex_lock(&wil->p2p_wdev_mutex); if (wil->scan_request) { struct wmi_scan_complete_event *data = d; struct cfg80211_scan_info info = { @@ -435,14 +436,13 @@ static void wmi_evt_scan_complete(struct wil6210_priv *wil, int id, wil->scan_request, info.aborted); del_timer_sync(&wil->scan_timer); - mutex_lock(&wil->p2p_wdev_mutex); cfg80211_scan_done(wil->scan_request, &info); wil->radio_wdev = wil->wdev; - mutex_unlock(&wil->p2p_wdev_mutex); wil->scan_request = NULL; } else { wil_err(wil, "SCAN_COMPLETE while not scanning\n"); } + mutex_unlock(&wil->p2p_wdev_mutex); } static void wmi_evt_connect(struct wil6210_priv *wil, int id, void *d, int len) -- 2.7.4