Re: [PATCH] rtl8xxxu: fix slab-out-of-bounds in rtl8xxxu_sta_add

From: Ping-Ke Shih

Date: Wed Dec 31 2025 - 03:08:20 EST


Ali Tariq <alitariq45892@xxxxxxxxx> wrote:

> The driver does not set hw->sta_data_size, which causes mac80211 to
> allocate insufficient space for driver private station data in
> __sta_info_alloc(). When rtl8xxxu_sta_add() accesses members of
> struct rtl8xxxu_sta_info through sta->drv_priv, this results in a
> slab-out-of-bounds write.
>
> KASAN report on RISC-V (VisionFive 2) with RTL8192EU adapter:
>
> BUG: KASAN: slab-out-of-bounds in rtl8xxxu_sta_add+0x31c/0x346
> Write of size 8 at addr ffffffd6d3e9ae88 by task kworker/u16:0/12
>
> Set hw->sta_data_size to sizeof(struct rtl8xxxu_sta_info) during
> probe, similar to how hw->vif_data_size is configured. This ensures
> mac80211 allocates sufficient space for the driver's per-station
> private data.
>
> Tested on StarFive VisionFive 2 v1.2A board.
>
> Fixes: eef55f1545c9 ("wifi: rtl8xxxu: support multiple interfaces in {add,remove}_interface()")
>
> Cc: stable@xxxxxxxxxxxxxxx
>
> Signed-off-by: Ali Tariq <alitariq45892@xxxxxxxxx>
> Reviewed-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>

1 patch(es) applied to rtw-next branch of rtw.git, thanks.

86c946bcc00f wifi: rtl8xxxu: fix slab-out-of-bounds in rtl8xxxu_sta_add

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https://github.com/pkshih/rtw.git