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

[Jia-Ju Bai]

On 2020/11/7 19:44, Kalle Valo wrote:
> Jia-Ju Bai <baijiaju1990@xxxxxxxxx> 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@xxxxxxxxx>
> 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

Okay, I have sent v2 patches just now.
Please have a look, thank :)


Best wishes,
Jia-Ju Bai