Re: [PATCH v5] char: pcmcia: synclink_cs: Fix use-after-free in mgslpc_ops

[Arnd Bergmann]

On Mon, Sep 19, 2022, at 6:02 AM, Hyunwoo Kim wrote:
> A race condition may occur if the user physically removes
> the pcmcia device while calling ioctl() for this tty device node.
>
> This is a race condition between the mgslpc_ioctl() function and
> the mgslpc_detach() function, which may eventually result in UAF.
>
> So, add a refcount check to mgslpc_detach() to free the structure
> after the tty device node is close()d.
>
> Signed-off-by: Hyunwoo Kim <imv4bel@xxxxxxxxx>

Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>