From 9379df2fd9234e3b67a23101c2370c99f6af6d77 Mon Sep 17 00:00:00 2001
From: Felix Fietkau <nbd@nbd.name>
Date: Sat, 14 Dec 2019 00:15:26 +0100
Subject: [PATCH] mt76: clear skb pointers from rx aggregation reorder buffer during cleanup
Git-commit: 9379df2fd9234e3b67a23101c2370c99f6af6d77
Patch-mainline: v5.7-rc1
References: jsc#SLE-13430

During the cleanup of the aggregation session, a rx handler (or release timer)
on another CPU might still hold a pointer to the reorder buffer and could
attempt to release some packets.
Clearing pointers during cleanup avoids a theoretical use-after-free bug here.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/wireless/mediatek/mt76/agg-rx.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/mediatek/mt76/agg-rx.c b/drivers/net/wireless/mediatek/mt76/agg-rx.c
index a4c64ae8fb1a..f77f03530259 100644
--- a/drivers/net/wireless/mediatek/mt76/agg-rx.c
+++ b/drivers/net/wireless/mediatek/mt76/agg-rx.c
@@ -276,6 +276,7 @@ static void mt76_rx_aggr_shutdown(struct mt76_dev *dev, struct mt76_rx_tid *tid)
 		if (!skb)
 			continue;
 
+		tid->reorder_buf[i] = NULL;
 		tid->nframes--;
 		dev_kfree_skb(skb);
 	}
-- 
2.16.4