2021-09-16 06:49:35

by Baochen Qiang

[permalink] [raw]
Subject: [PATCH v2] ath11k: Change DMA_FROM_DEVICE to DMA_TO_DEVICE when map reinjected packets

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 <[email protected]>
---
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 90da56316e7e..a55dff784724 100644
--- a/drivers/net/wireless/ath/ath11k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath11k/dp_rx.c
@@ -3434,7 +3434,7 @@ 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;

@@ -3499,7 +3499,7 @@ static int ath11k_dp_rx_h_defrag_reo_reinject(struct ath11k *ar, struct dp_rx_ti
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;
}

--
2.25.1


2021-09-28 14:07:50

by Kalle Valo

[permalink] [raw]
Subject: Re: [PATCH v2] ath11k: Change DMA_FROM_DEVICE to DMA_TO_DEVICE when map reinjected packets

Baochen Qiang <[email protected]> wrote:

> 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 <[email protected]>
> Signed-off-by: Kalle Valo <[email protected]>

Patch applied to ath-next branch of ath.git, thanks.

86a03dad0f5a ath11k: Change DMA_FROM_DEVICE to DMA_TO_DEVICE when map reinjected packets

--
https://patchwork.kernel.org/project/linux-wireless/patch/[email protected]/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches