mwifiex: check driver status in connect and scan handlers

Ignore scan and connection requests from cfg80211 when driver
unload is in process or previous command has timed out due to
a firmware bug. This patch fixes corner case system crash
issues.

Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Cathy Luo <cluo@marvell.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/mwifiex/cfg80211.c

@@ -1786,6 +1786,7 @@ mwifiex_cfg80211_connect(struct wiphy *wiphy, struct net_device *dev,
 			 struct cfg80211_connect_params *sme)
 {
 	struct mwifiex_private *priv = mwifiex_netdev_get_priv(dev);
+	struct mwifiex_adapter *adapter = priv->adapter;
 	int ret;
 
 	if (GET_BSS_ROLE(priv) != MWIFIEX_BSS_ROLE_STA) {
@@ -1800,6 +1801,13 @@ mwifiex_cfg80211_connect(struct wiphy *wiphy, struct net_device *dev,
 		return -EALREADY;
 	}
 
+	if (adapter->surprise_removed || adapter->is_cmd_timedout) {
+		wiphy_err(wiphy,
+			  "%s: Ignore connection. Card removed or FW in bad state\n",
+			  dev->name);
+		return -EFAULT;
+	}
+
 	wiphy_dbg(wiphy, "info: Trying to associate to %s and bssid %pM\n",
 		  (char *) sme->ssid, sme->bssid);
 

drivers/net/wireless/mwifiex/scan.c

@@ -1429,6 +1429,12 @@ int mwifiex_scan_networks(struct mwifiex_private *priv,
 		return -EBUSY;
 	}
 
+	if (adapter->surprise_removed || adapter->is_cmd_timedout) {
+		dev_err(adapter->dev,
+			"Ignore scan. Card removed or firmware in bad state\n");
+		return -EFAULT;
+	}
+
 	spin_lock_irqsave(&adapter->mwifiex_cmd_lock, flags);
 	adapter->scan_processing = true;
 	spin_unlock_irqrestore(&adapter->mwifiex_cmd_lock, flags);