From: Lior David <qca_liord@xxxxxxxxxxxxxxxx>
Fix 2 race conditions found during test runs of P2P discovery:
1. Because wil_p2p_cancel_listen was not protected, user space
could start a new P2P listen/search before wmi_stop_discovery
completed. This caused a crash in the firmware.
2. In P2P listen, when listen timer expires and user space calls
cancel_remain_on_channel at the same time, code could send the
cfg80211_remain_on_channel_expired notification twice.
Added protections with wil->mutex to several places that call
wmi_stop_discovery.
Signed-off-by: Lior David <qca_liord@xxxxxxxxxxxxxxxx>
Signed-off-by: Maya Erez <qca_merez@xxxxxxxxxxxxxxxx>
---
drivers/net/wireless/ath/wil6210/cfg80211.c | 9 +++--
drivers/net/wireless/ath/wil6210/main.c | 2 +-
drivers/net/wireless/ath/wil6210/p2p.c | 63 ++++++++++++++++++++---------
drivers/net/wireless/ath/wil6210/wil6210.h | 4 +-
4 files changed, 53 insertions(+), 25 deletions(-)
diff --git a/drivers/net/wireless/ath/wil6210/cfg80211.c b/drivers/net/wireless/ath/wil6210/cfg80211.c
index 24f9829..e867c76 100644
--- a/drivers/net/wireless/ath/wil6210/cfg80211.c
+++ b/drivers/net/wireless/ath/wil6210/cfg80211.c
@@ -387,7 +387,7 @@ static int wil_cfg80211_scan(struct wiphy *wiphy,
return rc;
}
- wil_p2p_stop_discovery(wil);
+ (void)wil_p2p_stop_discovery(wil);
wil_dbg_misc(wil, "Start scan_request 0x%p\n", request);
wil_dbg_misc(wil, "SSID count: %d", request->n_ssids);
@@ -868,6 +868,9 @@ static int wil_cfg80211_set_default_key(struct wiphy *wiphy,
u8 key_index, bool unicast,
bool multicast)
{
+ struct wil6210_priv *wil = wiphy_to_wil(wiphy);
+
+ wil_dbg_misc(wil, "%s: entered\n", __func__);
return 0;
}
@@ -903,9 +906,7 @@ static int wil_cancel_remain_on_channel(struct wiphy *wiphy,
wil_dbg_misc(wil, "%s()\n", __func__);
- wil_p2p_cancel_listen(wil, cookie);
-
- return 0;
+ return wil_p2p_cancel_listen(wil, cookie);
}
/**
diff --git a/drivers/net/wireless/ath/wil6210/main.c b/drivers/net/wireless/ath/wil6210/main.c
index e09e9bb..05a4ae7 100644
--- a/drivers/net/wireless/ath/wil6210/main.c
+++ b/drivers/net/wireless/ath/wil6210/main.c
@@ -984,7 +984,7 @@ int __wil_down(struct wil6210_priv *wil)
}
wil_enable_irq(wil);
- wil_p2p_stop_discovery(wil);
+ (void)wil_p2p_stop_discovery(wil);
if (wil->scan_request) {
wil_dbg_misc(wil, "Abort scan_request 0x%p\n",
diff --git a/drivers/net/wireless/ath/wil6210/p2p.c b/drivers/net/wireless/ath/wil6210/p2p.c
index d223648..2c1b895 100644
--- a/drivers/net/wireless/ath/wil6210/p2p.c
+++ b/drivers/net/wireless/ath/wil6210/p2p.c
@@ -156,26 +156,42 @@ out:
return rc;
}
-void wil_p2p_stop_discovery(struct wil6210_priv *wil)
+u8 wil_p2p_stop_discovery(struct wil6210_priv *wil)
{
struct wil_p2p_info *p2p = &wil->p2p;
+ u8 started = p2p->discovery_started;
if (p2p->discovery_started) {
del_timer_sync(&p2p->discovery_timer);
p2p->discovery_started = 0;
wmi_stop_discovery(wil);
}
+
+ return started;
}
-void wil_p2p_cancel_listen(struct wil6210_priv *wil, u64 cookie)
+int wil_p2p_cancel_listen(struct wil6210_priv *wil, u64 cookie)
{
struct wil_p2p_info *p2p = &wil->p2p;
+ u8 started;
+
+ mutex_lock(&wil->mutex);
- if (cookie != p2p->cookie)
+ if (cookie != p2p->cookie) {
wil_info(wil, "%s: Cookie mismatch: 0x%016llx vs. 0x%016llx\n",
__func__, p2p->cookie, cookie);
+ mutex_unlock(&wil->mutex);
+ return -ENOENT;
+ }
+
+ started = wil_p2p_stop_discovery(wil);
+
+ mutex_unlock(&wil->mutex);
- wil_p2p_stop_discovery(wil);
+ if (!started) {
+ wil_err(wil, "%s: listen not started\n", __func__);
+ return -ENOENT;
+ }
mutex_lock(&wil->p2p_wdev_mutex);
cfg80211_remain_on_channel_expired(wil->radio_wdev,
@@ -184,6 +200,7 @@ void wil_p2p_cancel_listen(struct wil6210_priv *wil, u64 cookie)
GFP_KERNEL);
wil->radio_wdev = wil->wdev;
mutex_unlock(&wil->p2p_wdev_mutex);
+ return 0;
}
void wil_p2p_listen_expired(struct work_struct *work)
@@ -192,18 +209,23 @@ void wil_p2p_listen_expired(struct work_struct *work)
struct wil_p2p_info, discovery_expired_work);
struct wil6210_priv *wil = container_of(p2p,
struct wil6210_priv, p2p);
+ u8 started;
wil_dbg_misc(wil, "%s()\n", __func__);
- wil_p2p_stop_discovery(wil);
+ mutex_lock(&wil->mutex);
+ started = wil_p2p_stop_discovery(wil);
+ mutex_unlock(&wil->mutex);
- mutex_lock(&wil->p2p_wdev_mutex);
- cfg80211_remain_on_channel_expired(wil->radio_wdev,
- p2p->cookie,
- &p2p->listen_chan,
- GFP_KERNEL);
- wil->radio_wdev = wil->wdev;
- mutex_unlock(&wil->p2p_wdev_mutex);
+ if (started) {
+ mutex_lock(&wil->p2p_wdev_mutex);
+ cfg80211_remain_on_channel_expired(wil->radio_wdev,
+ p2p->cookie,
+ &p2p->listen_chan,
+ GFP_KERNEL);
+ wil->radio_wdev = wil->wdev;
+ mutex_unlock(&wil->p2p_wdev_mutex);
+ }
}
@@ -213,14 +235,19 @@ void wil_p2p_search_expired(struct work_struct *work)
struct wil_p2p_info, discovery_expired_work);
struct wil6210_priv *wil = container_of(p2p,
struct wil6210_priv, p2p);
+ u8 started;
wil_dbg_misc(wil, "%s()\n", __func__);
- wil_p2p_stop_discovery(wil);
+ mutex_lock(&wil->mutex);
+ started = wil_p2p_stop_discovery(wil);
+ mutex_unlock(&wil->mutex);
- mutex_lock(&wil->p2p_wdev_mutex);
- cfg80211_scan_done(wil->scan_request, 0);
- wil->scan_request = NULL;
- wil->radio_wdev = wil->wdev;
- mutex_unlock(&wil->p2p_wdev_mutex);
+ if (started) {
+ mutex_lock(&wil->p2p_wdev_mutex);
+ cfg80211_scan_done(wil->scan_request, 0);
+ wil->scan_request = NULL;
+ wil->radio_wdev = wil->wdev;
+ mutex_unlock(&wil->p2p_wdev_mutex);
+ }
}
diff --git a/drivers/net/wireless/ath/wil6210/wil6210.h b/drivers/net/wireless/ath/wil6210/wil6210.h
index 9b77a08..68f60ea 100644
--- a/drivers/net/wireless/ath/wil6210/wil6210.h
+++ b/drivers/net/wireless/ath/wil6210/wil6210.h
@@ -775,8 +775,8 @@ int wil_p2p_search(struct wil6210_priv *wil,
struct cfg80211_scan_request *request);
int wil_p2p_listen(struct wil6210_priv *wil, unsigned int duration,
struct ieee80211_channel *chan, u64 *cookie);
-void wil_p2p_stop_discovery(struct wil6210_priv *wil);
-void wil_p2p_cancel_listen(struct wil6210_priv *wil, u64 cookie);
+u8 wil_p2p_stop_discovery(struct wil6210_priv *wil);
+int wil_p2p_cancel_listen(struct wil6210_priv *wil, u64 cookie);
void wil_p2p_listen_expired(struct work_struct *work);
void wil_p2p_search_expired(struct work_struct *work);
--
1.8.5.2
--
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