From 753ffad3d6243303994227854d951ff5c70fa9e0 Mon Sep 17 00:00:00 2001 From: Fredrik Olofsson Date: Tue, 19 Nov 2019 14:34:51 +0100 Subject: mac80211: fix TID field in monitor mode transmit Fix overwriting of the qos_ctrl.tid field for encrypted frames injected on a monitor interface. While qos_ctrl.tid is not encrypted, it's used as an input into the encryption algorithm so it's protected, and thus cannot be modified after encryption. For injected frames, the encryption may already have been done in userspace, so we cannot change any fields. Before passing the frame to the driver, the qos_ctrl.tid field is updated from skb->priority. Prior to dbd50a851c50 skb->priority was updated in ieee80211_select_queue_80211(), but this function is no longer always called. Update skb->priority in ieee80211_monitor_start_xmit() so that the value is stored, and when later code 'modifies' the TID it really sets it to the same value as before, preserving the encryption. Fixes: dbd50a851c50 ("mac80211: only allocate one queue when using iTXQs") Signed-off-by: Fredrik Olofsson Link: https://lore.kernel.org/r/20191119133451.14711-1-fredrik.olofsson@anyfinetworks.com [rewrite commit message based on our discussion] Signed-off-by: Johannes Berg --- net/mac80211/tx.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'net/mac80211') diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index b696b9136f4c..38b58a00db46 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -2256,6 +2256,15 @@ netdev_tx_t ieee80211_monitor_start_xmit(struct sk_buff *skb, payload[7]); } + /* + * Initialize skb->priority for QoS frames. This is put in the TID field + * of the frame before passing it to the driver. + */ + if (ieee80211_is_data_qos(hdr->frame_control)) { + u8 *p = ieee80211_get_qos_ctl(hdr); + skb->priority = *p & IEEE80211_QOS_CTL_TAG1D_MASK; + } + memset(info, 0, sizeof(*info)); info->flags = IEEE80211_TX_CTL_REQ_TX_STATUS | -- cgit v1.2.3