Patch "mac80211: don't use napi_gro_receive() outside NAPI context" has been added to the 4.0-stable tree

[<gregkh@linuxfoundation.org>]

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

    mac80211: don't use napi_gro_receive() outside NAPI context

to the 4.0-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-use-napi_gro_receive-outside-napi-context.patch
and it can be found in the queue-4.0 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 22d3a3c829fa9ecdb493d1f1f2838d543f8d86a3 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Tue, 19 May 2015 15:40:21 +0200
Subject: mac80211: don't use napi_gro_receive() outside NAPI context

From: Johannes Berg <johannes.berg@intel.com>

commit 22d3a3c829fa9ecdb493d1f1f2838d543f8d86a3 upstream.

No matter how the driver manages its NAPI context, there's no way
sending frames to it from a timer can be correct, since it would
corrupt the internal GRO lists.

To avoid that, always use the non-NAPI path when releasing frames
from the timer.

Reported-by: Jean Trivelly <jean.trivelly@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 net/mac80211/ieee80211_i.h |    3 +++
 net/mac80211/rx.c          |    5 +++--
 2 files changed, 6 insertions(+), 2 deletions(-)

--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -204,6 +204,8 @@ enum ieee80211_packet_rx_flags {
  * @IEEE80211_RX_CMNTR: received on cooked monitor already
  * @IEEE80211_RX_BEACON_REPORTED: This frame was already reported
  *	to cfg80211_report_obss_beacon().
+ * @IEEE80211_RX_REORDER_TIMER: this frame is released by the
+ *	reorder buffer timeout timer, not the normal RX path
  *
  * These flags are used across handling multiple interfaces
  * for a single frame.
@@ -211,6 +213,7 @@ enum ieee80211_packet_rx_flags {
 enum ieee80211_rx_flags {
 	IEEE80211_RX_CMNTR		= BIT(0),
 	IEEE80211_RX_BEACON_REPORTED	= BIT(1),
+	IEEE80211_RX_REORDER_TIMER	= BIT(2),
 };
 
 struct ieee80211_rx_data {
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2106,7 +2106,8 @@ ieee80211_deliver_skb(struct ieee80211_r
 		/* deliver to local stack */
 		skb->protocol = eth_type_trans(skb, dev);
 		memset(skb->cb, 0, sizeof(skb->cb));
-		if (rx->local->napi)
+		if (!(rx->flags & IEEE80211_RX_REORDER_TIMER) &&
+		    rx->local->napi)
 			napi_gro_receive(rx->local->napi, skb);
 		else
 			netif_receive_skb(skb);
@@ -3215,7 +3216,7 @@ void ieee80211_release_reorder_timeout(s
 		/* This is OK -- must be QoS data frame */
 		.security_idx = tid,
 		.seqno_idx = tid,
-		.flags = 0,
+		.flags = IEEE80211_RX_REORDER_TIMER,
 	};
 	struct tid_ampdu_rx *tid_agg_rx;
 


Patches currently in stable-queue which might be from johannes.berg@intel.com are

queue-4.0/mac80211-don-t-use-napi_gro_receive-outside-napi-context.patch
queue-4.0/mac80211-move-wep-tailroom-size-check.patch