mac80211: Fix scan RX processing oops

ieee80211_bss_info_update() can return NULL. Verify that this is not the
case before calling ieee802111_rx_bss_put() which would trigger an oops
in interrupt context in atomic_dec_and_lock().

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Benoit Papillault <benoit.papillault@free.fr>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 8e6685e7ae85..416bb41099f3 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -388,7 +388,8 @@ ieee80211_scan_rx(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb,
         bss = ieee80211_bss_info_update(sdata->local, rx_status,
                                         mgmt, skb->len, &elems,
                                         freq, beacon);
-        ieee80211_rx_bss_put(sdata->local, bss);
+        if (bss)
+                ieee80211_rx_bss_put(sdata->local, bss);
 
         dev_kfree_skb(skb);
         return RX_QUEUED;