mac80211: fix TX status cookie in HW offload case

When the off-channel TX is done with remain-on-channel
offloaded to hardware, the reported cookie is wrong as
in that case we shouldn't use the SKB as the cookie but
need to instead use the corresponding r-o-c cookie
(XOR'ed with 2 to prevent API mismatches).

Fix this by keeping track of the hw_roc_skb pointer
just for the status processing and use the correct
cookie to report in this case. We can't use the
hw_roc_skb pointer itself because it is NULL'ed when
the frame is transmitted to prevent it being used
twice.

This fixes a bug where the P2P state machine in the
supplicant gets stuck because it never gets a correct
result for its transmitted frame.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 4bc8a9250cfd..9cd73b11506e 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1822,6 +1822,7 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev,
                 *cookie ^= 2;
                 IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_TX_OFFCHAN;
                 local->hw_roc_skb = skb;
+                local->hw_roc_skb_for_status = skb;
                 mutex_unlock(&local->mtx);
 
                 return 0;
@@ -1875,6 +1876,7 @@ static int ieee80211_mgmt_tx_cancel_wait(struct wiphy *wiphy,
                 if (ret == 0) {
                         kfree_skb(local->hw_roc_skb);
                         local->hw_roc_skb = NULL;
+                        local->hw_roc_skb_for_status = NULL;
                 }
 
                 mutex_unlock(&local->mtx);