2019-12-22 15:07:37

by Felix Fietkau

[permalink] [raw]
Subject: [PATCH 4/4] mt76: clear skb pointers from rx aggregation reorder buffer during cleanup

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 <[email protected]>
---
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 6d64c2c4a159..3815d28a32ea 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);
}
--
2.24.0