When I introduced in-kernel off-channel TX I
introduced a bug -- the work can't be canceled
again because the code clear the skb pointer.
Fix this by keeping track separately of whether
TX status has already been reported.
Cc: stable@kernel.org [2.6.38+]
Reported-by: Jouni Malinen <j@w1.fi>
Tested-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
         * so in that case userspace will have to deal with it.
         */
 
-       if (wk->offchan_tx.wait && wk->offchan_tx.frame)
+       if (wk->offchan_tx.wait && !wk->offchan_tx.status)
                cfg80211_mgmt_tx_status(wk->sdata->dev,
                                        (unsigned long) wk->offchan_tx.frame,
                                        wk->ie, wk->ie_len, false, GFP_KERNEL);
 
                struct {
                        struct sk_buff *frame;
                        u32 wait;
+                       bool status;
                } offchan_tx;
        };
 
 
                                continue;
                        if (wk->offchan_tx.frame != skb)
                                continue;
-                       wk->offchan_tx.frame = NULL;
+                       wk->offchan_tx.status = true;
                        break;
                }
                rcu_read_unlock();
 
                /*
                 * After this, offchan_tx.frame remains but now is no
                 * longer a valid pointer -- we still need it as the
-                * cookie for canceling this work.
+                * cookie for canceling this work/status matching.
                 */
                ieee80211_tx_skb(wk->sdata, wk->offchan_tx.frame);