[PATCH 5.14 235/849] ath11k: Change DMA_FROM_DEVICE to DMA_TO_DEVICE when map reinjected packets

Greg Kroah-Hartman
2021-11-15T22:21:55Z

From: Baochen Qiang <bqiang@codeaurora.org>

[ Upstream commit 86a03dad0f5ad8182ed5fcf7bf3eec71cd96577c ]

For fragmented packets, ath11k reassembles each fragment as a normal
packet and then reinjects it into HW ring. In this case, the DMA
direction should be DMA_TO_DEVICE, not DMA_FROM_DEVICE, otherwise
invalid payload will be reinjected to HW and then delivered to host.
What is more, since arbitrary memory could be allocated to the frame, we
don't know what kind of data is contained in the buffer reinjected.
Thus, as a bad result, private info may be leaked.

Note that this issue is only found on Intel platform.

Tested-on: QCA6390 hw2.0 PCI WLAN.HST.1.0.1-01740-QCAHSTSWPLZ_V2_TO_X86-1
Signed-off-by: Baochen Qiang <bqiang@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210916064617.20006-1-bqiang@codeaurora.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/ath/ath11k/dp_rx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c
index 603d2f93ac18f..d4f7304a35ec1 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -3315,7 +3315,7 @@ static int ath11k_dp_rx_h_defrag_reo_reinject(struct ath11k *ar, struct dp_rx_ti

paddr = dma_map_single(ab->dev, defrag_skb->data,
defrag_skb->len + skb_tailroom(defrag_skb),
- DMA_FROM_DEVICE);
+ DMA_TO_DEVICE);
if (dma_mapping_error(ab->dev, paddr))
return -ENOMEM;

@@ -3380,7 +3380,7 @@ err_free_idr:
spin_unlock_bh(&rx_refill_ring->idr_lock);
err_unmap_dma:
dma_unmap_single(ab->dev, paddr, defrag_skb->len + skb_tailroom(defrag_skb),
- DMA_FROM_DEVICE);
+ DMA_TO_DEVICE);
return ret;
}

--
2.33.0