Re: [PATCH] firmware/imx-dsp: Fix use_after_free in imx_dsp_setup_channels()

[Daniel Baluta]

On Sun, Oct 8, 2023 at 6:30 AM Hao Ge <gehao@xxxxxxxxxx> wrote:
>
> dsp_chan->name and chan_name points to same block of memory,
> because dev_err still needs to be used it,so we need free
> it's memory after use to avoid use_after_free.
>
> Fixes: e527adfb9b7d ("firmware: imx-dsp: Fix an error handling path in imx_dsp_setup_channels()")
> Signed-off-by: Hao Ge <gehao@xxxxxxxxxx>

Reviewed-by: Daniel Baluta <daniel.baluta@xxxxxxx>

> ---
>  drivers/firmware/imx/imx-dsp.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/firmware/imx/imx-dsp.c b/drivers/firmware/imx/imx-dsp.c
> index 508eab346fc6..a48a58e0c61f 100644
> --- a/drivers/firmware/imx/imx-dsp.c
> +++ b/drivers/firmware/imx/imx-dsp.c
> @@ -114,11 +114,11 @@ static int imx_dsp_setup_channels(struct imx_dsp_ipc *dsp_ipc)
>                 dsp_chan->idx = i % 2;
>                 dsp_chan->ch = mbox_request_channel_byname(cl, chan_name);
>                 if (IS_ERR(dsp_chan->ch)) {
> -                       kfree(dsp_chan->name);
>                         ret = PTR_ERR(dsp_chan->ch);
>                         if (ret != -EPROBE_DEFER)
>                                 dev_err(dev, "Failed to request mbox chan %s ret %d\n",
>                                         chan_name, ret);
> +                       kfree(dsp_chan->name);
>                         goto out;
>                 }
>
> --
> 2.25.1
>