Re: [PATCH] media: imon: Fix null-ptr-deref in imon_probe

[Andrey Konovalov]

On Mon, Oct 9, 2017 at 8:14 PM, Arvind Yadav <arvind.yadav.cs@xxxxxxxxx> wrote:
> It seems that the return value of usb_ifnum_to_if() can be NULL and
> needs to be checked.

Hi Arvind,

Your patch fixes the issue.

Thanks!

Tested-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>

>
> Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
> ---
> This bug report by Andrey Konovalov usb/media/imon: null-ptr-deref
> in imon_probe
>
>  drivers/media/rc/imon.c | 5 +++++
>  1 file changed, 5 insertions(+)
>
> diff --git a/drivers/media/rc/imon.c b/drivers/media/rc/imon.c
> index 7b3f31c..0c46155 100644
> --- a/drivers/media/rc/imon.c
> +++ b/drivers/media/rc/imon.c
> @@ -2517,6 +2517,11 @@ static int imon_probe(struct usb_interface *interface,
>         mutex_lock(&driver_lock);
>
>         first_if = usb_ifnum_to_if(usbdev, 0);
> +       if (!first_if) {
> +               ret = -ENODEV;
> +               goto fail;
> +       }
> +
>         first_if_ctx = usb_get_intfdata(first_if);
>
>         if (ifnum == 0) {
> --
> 2.7.4
>