Re: [PATCH] rtl8192ce: avoid accessing the data mapped to streaming DMA

Kalle Valo
2020-11-07T11:44:29Z

Jia-Ju Bai <baijiaju1990@gmail.com> wrote:

> In rtl92ce_tx_fill_cmddesc(), skb->data is mapped to streaming DMA on
> line 530:
> dma_addr_t mapping = dma_map_single(..., skb->data, ...);
>
> On line 533, skb->data is assigned to hdr after cast:
> struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
>
> Then hdr->frame_control is accessed on line 534:
> __le16 fc = hdr->frame_control;
>
> This DMA access may cause data inconsistency between CPU and hardwre.
>
> To fix this bug, hdr->frame_control is accessed before the DMA mapping.
>
> Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>

Like Ping said, use "rtlwifi:" prefix and have all rtlwifi patches in
the same patchset.

4 patches set to Changes Requested.

11843533 rtl8192ce: avoid accessing the data mapped to streaming DMA
11843541 rtl8192de: avoid accessing the data mapped to streaming DMA
11843553 rtl8723ae: avoid accessing the data mapped to streaming DMA
11843557 rtl8188ee: avoid accessing the data mapped to streaming DMA

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