cfg80211: hold BSS over association process

This fixes the potential issue that the BSS struct that we use
and later assign to wdev->current_bss is removed from the scan
list while associating.

Also warn when we don't have a BSS struct in connect_result
unless it's from a driver that only has the connect() API.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

2 files changed, 14 insertions, 5 deletions

diff --git a/net/wireless/mlme.c b/net/wireless/mlme.c
index dd6f79d7bd2e..bfac5e186f57 100644
--- a/net/wireless/mlme.c
+++ b/net/wireless/mlme.c
@@ -38,6 +38,7 @@ void cfg80211_rx_assoc_resp(struct net_device *dev, struct cfg80211_bss *bss,
          * frame instead of reassoc.
          */
         if (cfg80211_sme_rx_assoc_resp(wdev, status_code)) {
+                cfg80211_unhold_bss(bss_from_pub(bss));
                 cfg80211_put_bss(wiphy, bss);
                 return;
         }
@@ -142,6 +143,7 @@ void cfg80211_assoc_timeout(struct net_device *dev, struct cfg80211_bss *bss)
         nl80211_send_assoc_timeout(rdev, dev, bss->bssid, GFP_KERNEL);
         cfg80211_sme_assoc_timeout(wdev);
 
+        cfg80211_unhold_bss(bss_from_pub(bss));
         cfg80211_put_bss(wiphy, bss);
 }
 EXPORT_SYMBOL(cfg80211_assoc_timeout);
@@ -309,6 +311,8 @@ int cfg80211_mlme_assoc(struct cfg80211_registered_device *rdev,
                 goto out;
 
         err = rdev_assoc(rdev, dev, req);
+        if (!err)
+                cfg80211_hold_bss(bss_from_pub(req->bss));
 
 out:
         if (err)
diff --git a/net/wireless/sme.c b/net/wireless/sme.c
index ae7e2cbf45cb..c0bf781d4fbe 100644
--- a/net/wireless/sme.c
+++ b/net/wireless/sme.c
@@ -615,19 +615,24 @@ void __cfg80211_connect_result(struct net_device *dev, const u8 *bssid,
                 kfree(wdev->connect_keys);
                 wdev->connect_keys = NULL;
                 wdev->ssid_len = 0;
-                cfg80211_put_bss(wdev->wiphy, bss);
+                if (bss) {
+                        cfg80211_unhold_bss(bss_from_pub(bss));
+                        cfg80211_put_bss(wdev->wiphy, bss);
+                }
                 return;
         }
 
-        if (!bss)
+        if (!bss) {
+                WARN_ON_ONCE(!wiphy_to_dev(wdev->wiphy)->ops->connect);
                 bss = cfg80211_get_bss(wdev->wiphy, NULL, bssid,
                                        wdev->ssid, wdev->ssid_len,
                                        WLAN_CAPABILITY_ESS,
                                        WLAN_CAPABILITY_ESS);
-        if (WARN_ON(!bss))
-                return;
+                if (WARN_ON(!bss))
+                        return;
+                cfg80211_hold_bss(bss_from_pub(bss));
+        }
 
-        cfg80211_hold_bss(bss_from_pub(bss));
         wdev->current_bss = bss_from_pub(bss);
 
         cfg80211_upload_connect_keys(wdev);