Re: [PATCH] firmware: Always initialize the fw_priv list object

[Rafael J. Wysocki]

On Thu, Sep 20, 2018 at 3:07 AM Bjorn Andersson
<bjorn.andersson@xxxxxxxxxx> wrote:
>
> When freeing the fw_priv the item is taken off the list. This causes an
> oops in the FW_OPT_NOCACHE case as the list object is not initialized.
>
> Make sure to initialize the list object regardless of this flag.
>
> Fixes: 422b3db2a503 ("firmware: Fix security issue with request_firmware_into_buf()")
> Cc: stable@xxxxxxxxxxxxxxx
> Cc: Rishabh Bhatnagar <rishabhb@xxxxxxxxxxxxxx>
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> ---
>  drivers/base/firmware_loader/main.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/base/firmware_loader/main.c b/drivers/base/firmware_loader/main.c
> index b3c0498ee433..8e9213b36e31 100644
> --- a/drivers/base/firmware_loader/main.c
> +++ b/drivers/base/firmware_loader/main.c
> @@ -226,8 +226,11 @@ static int alloc_lookup_fw_priv(const char *fw_name,
>         }
>
>         tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
> -       if (tmp && !(opt_flags & FW_OPT_NOCACHE))
> -               list_add(&tmp->list, &fwc->head);
> +       if (tmp) {
> +               INIT_LIST_HEAD(&tmp->list);
> +               if (!(opt_flags & FW_OPT_NOCACHE))
> +                       list_add(&tmp->list, &fwc->head);
> +       }
>         spin_unlock(&fwc->lock);
>
>         *fw_priv = tmp;
> --

Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>