Patch "mac80211: don't look at the PM bit of BAR frames" has been added to the 4.4-stable tree

Patch "mac80211: don't look at the PM bit of BAR frames" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    mac80211: don't look at the PM bit of BAR frames

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mac80211-don-t-look-at-the-pm-bit-of-bar-frames.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 769dc04db3ed8484798aceb015b94deacc2ba557 Mon Sep 17 00:00:00 2001
From: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Date: Thu, 8 Jun 2017 14:00:49 +0300
Subject: mac80211: don't look at the PM bit of BAR frames

From: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

commit 769dc04db3ed8484798aceb015b94deacc2ba557 upstream.

When a peer sends a BAR frame with PM bit clear, we should
not modify its PM state as madated by the spec in
802.11-20012 10.2.1.2.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/mac80211/rx.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1455,12 +1455,16 @@ ieee80211_rx_h_sta_process(struct ieee80
 	 */
 	if (!ieee80211_hw_check(&sta->local->hw, AP_LINK_PS) &&
 	    !ieee80211_has_morefrags(hdr->frame_control) &&
+	    !ieee80211_is_back_req(hdr->frame_control) &&
 	    !(status->rx_flags & IEEE80211_RX_DEFERRED_RELEASE) &&
 	    (rx->sdata->vif.type == NL80211_IFTYPE_AP ||
 	     rx->sdata->vif.type == NL80211_IFTYPE_AP_VLAN) &&
-	    /* PM bit is only checked in frames where it isn't reserved,
+	    /*
+	     * PM bit is only checked in frames where it isn't reserved,
 	     * in AP mode it's reserved in non-bufferable management frames
 	     * (cf. IEEE 802.11-2012 8.2.4.1.7 Power Management field)
+	     * BAR frames should be ignored as specified in
+	     * IEEE 802.11-2012 10.2.1.2.
 	     */
 	    (!ieee80211_is_mgmt(hdr->frame_control) ||
 	     ieee80211_is_bufferable_mmpdu(hdr->frame_control))) {


Patches currently in stable-queue which might be from emmanuel.grumbach@intel.com are

queue-4.4/mac80211-don-t-look-at-the-pm-bit-of-bar-frames.patch