From: Deren Wu deren.wu@mediatek.com
[ Upstream commit 5f54237ad798f41cb6a503271aa9ca47188cfb9b ]
Ensure the entry has been fully updated before SDIO bus worker access it. This patch would fix potential memory risk in both mt7663s and mt7921s.
Fixes: 764dee47e2c1 ("mt76: sdio: move common code in mt76_sdio module") Signed-off-by: Deren Wu deren.wu@mediatek.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Signed-off-by: Felix Fietkau nbd@nbd.name Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/wireless/mediatek/mt76/sdio.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/drivers/net/wireless/mediatek/mt76/sdio.c b/drivers/net/wireless/mediatek/mt76/sdio.c index 228bc7d45011c..419723118ded8 100644 --- a/drivers/net/wireless/mediatek/mt76/sdio.c +++ b/drivers/net/wireless/mediatek/mt76/sdio.c @@ -562,6 +562,10 @@ mt76s_tx_queue_skb_raw(struct mt76_dev *dev, struct mt76_queue *q,
q->entry[q->head].buf_sz = len; q->entry[q->head].skb = skb; + + /* ensure the entry fully updated before bus access */ + smp_wmb(); + q->head = (q->head + 1) % q->ndesc; q->queued++;