[PATCH 5.15 238/279] mac80211: drop check for DONT_REORDER in __ieee80211_select_queue

Greg Kroah-Hartman
2021-11-24T14:04:06Z

From: Felix Fietkau <nbd@nbd.name>

commit f6ab25d41b18f3d26883cb9c20875e1a85c4f05b upstream.

When __ieee80211_select_queue is called, skb->cb has not been cleared yet,
which means that info->control.flags can contain garbage.
In some cases this leads to IEEE80211_TX_CTRL_DONT_REORDER being set, causing
packets marked for other queues to randomly end up in BE instead.

This flag only needs to be checked in ieee80211_select_queue_80211, since
the radiotap parser is the only piece of code that sets it

Fixes: 66d06c84730c ("mac80211: adhere to Tx control flag that prevents frame reordering")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20211110212201.35452-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/mac80211/wme.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/net/mac80211/wme.c
+++ b/net/mac80211/wme.c
@@ -143,7 +143,6 @@ u16 ieee80211_select_queue_80211(struct
u16 __ieee80211_select_queue(struct ieee80211_sub_if_data *sdata,
struct sta_info *sta, struct sk_buff *skb)
{
- struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
struct mac80211_qos_map *qos_map;
bool qos;

@@ -156,7 +155,7 @@ u16 __ieee80211_select_queue(struct ieee
else
qos = false;

- if (!qos || (info->control.flags & IEEE80211_TX_CTRL_DONT_REORDER)) {
+ if (!qos) {
skb->priority = 0; /* required for correct WPA/11i MIC */
return IEEE80211_AC_BE;
}