mac80211: assign seqnums for group QoS frames

According to 802.11-2012 9.3.2.10, paragraph 4, QoS
data frames with a group address in the Address 1 field
have sequence numbers allocated from the same counter
as non-QoS data and management frames.  Without this
flag, some drivers may not assign sequence numbers, and
in rare cases frames might get dropped.  Set the control
flag accordingly.

Signed-off-by: Bob Copeland <bob@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 098ae854ad3c..3456c0486b48 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -781,9 +781,11 @@ ieee80211_tx_h_sequence(struct ieee80211_tx_data *tx)
         /*
          * Anything but QoS data that has a sequence number field
          * (is long enough) gets a sequence number from the global
-         * counter.
+         * counter.  QoS data frames with a multicast destination
+         * also use the global counter (802.11-2012 9.3.2.10).
          */
-        if (!ieee80211_is_data_qos(hdr->frame_control)) {
+        if (!ieee80211_is_data_qos(hdr->frame_control) ||
+            is_multicast_ether_addr(hdr->addr1)) {
                 /* driver should assign sequence number */
                 info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
                 /* for pure STA mode without beacons, we can do it */