mac80211: preserve more bits when building QoS header

Michael Braun reported that when trying to inject A-MSDUs over
monitor interfaces, the frame doesn't come out right since the
QoS header A-MSDU bit is overwritten.

Rather than adding that bit specifically simply preserve those
bits that we don't set here, since we typically get here with
a zeroed-out QoS header anyway.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Johannes Berg 2016-10-12 14:17:13 +02:00
parent 72f15d53f3
commit 32910bb951

View File

@ -236,26 +236,35 @@ void ieee80211_set_qos_hdr(struct ieee80211_sub_if_data *sdata,
{
struct ieee80211_hdr *hdr = (void *)skb->data;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
u8 tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
u8 flags;
u8 *p;
u8 ack_policy, tid;
if (!ieee80211_is_data_qos(hdr->frame_control))
return;
p = ieee80211_get_qos_ctl(hdr);
tid = skb->priority & IEEE80211_QOS_CTL_TAG1D_MASK;
/* preserve EOSP bit */
ack_policy = *p & IEEE80211_QOS_CTL_EOSP;
/* set up the first byte */
/*
* preserve everything but the TID and ACK policy
* (which we both write here)
*/
flags = *p & ~(IEEE80211_QOS_CTL_TID_MASK |
IEEE80211_QOS_CTL_ACK_POLICY_MASK);
if (is_multicast_ether_addr(hdr->addr1) ||
sdata->noack_map & BIT(tid)) {
ack_policy |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
flags |= IEEE80211_QOS_CTL_ACK_POLICY_NOACK;
info->flags |= IEEE80211_TX_CTL_NO_ACK;
}
/* qos header is 2 bytes */
*p++ = ack_policy | tid;
*p = flags | tid;
/* set up the second byte */
p++;
if (ieee80211_vif_is_mesh(&sdata->vif)) {
/* preserve RSPI and Mesh PS Level bit */
*p &= ((IEEE80211_QOS_CTL_RSPI |