mac80211: fix NULL pointer dereference in ieee80211_compatible_rates

Fix a possible NULL pointer dereference in ieee80211_compatible_rates
introduced in the patch "mac80211: fix association with some APs". If no bss
is available just use all supported rates in the association request.

Signed-off-by: Helmut Schaa <hschaa@suse.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index e470bf12b765..7cfd12e0d1e2 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -730,7 +730,17 @@ static void ieee80211_send_assoc(struct net_device *dev,
                 if (bss->wmm_ie) {
                         wmm = 1;
                 }
+
+                /* get all rates supported by the device and the AP as
+                 * some APs don't like getting a superset of their rates
+                 * in the association request (e.g. D-Link DAP 1353 in
+                 * b-only mode) */
+                rates_len = ieee80211_compatible_rates(bss, sband, &rates);
+
                 ieee80211_rx_bss_put(dev, bss);
+        } else {
+                rates = ~0;
+                rates_len = sband->n_bitrates;
         }
 
         mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
@@ -761,10 +771,7 @@ static void ieee80211_send_assoc(struct net_device *dev,
         *pos++ = ifsta->ssid_len;
         memcpy(pos, ifsta->ssid, ifsta->ssid_len);
 
-        /* all supported rates should be added here but some APs
-         * (e.g. D-Link DAP 1353 in b-only mode) don't like that
-         * Therefore only add rates the AP supports */
-        rates_len = ieee80211_compatible_rates(bss, sband, &rates);
+        /* add all rates which were marked to be used above */
         supp_rates_len = rates_len;
         if (supp_rates_len > 8)
                 supp_rates_len = 8;