Subject: Re: [PATCH net] ieee802154: Prevent user from crashing the host

From: Miquel Raynal <[email-masked]>
Date: Thu, 2 Mar 2023 09:48:48 +0100

Hello,

[email-masked] wrote on Wed,  1 Mar 2023 16:44:50 +0100:

> Avoid crashing the machine by checking
> info->attrs[NL802154_ATTR_SCAN_TYPE] presence before de-referencing it,
> which was the primary intend of the blamed patch.

Subject should have been wpan instead of net, sorry for the confusion.

> Reported-by: Sanan Hasanov <[email-masked]>
> Suggested-by: Eric Dumazet <[email-masked]>
> Fixes: a0b6106672b5 ("ieee802154: Convert scan error messages to extack")
> Signed-off-by: Miquel Raynal <[email-masked]>
> ---
>  net/ieee802154/nl802154.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/ieee802154/nl802154.c b/net/ieee802154/nl802154.c
> index 88380606af2c..a18fb98a4b09 100644
> --- a/net/ieee802154/nl802154.c
> +++ b/net/ieee802154/nl802154.c
> @@ -1412,7 +1412,7 @@ static int nl802154_trigger_scan(struct sk_buff *skb, struct genl_info *info)
>  		return -EOPNOTSUPP;
>  	}
>  
> -	if (!nla_get_u8(info->attrs[NL802154_ATTR_SCAN_TYPE])) {
> +	if (!info->attrs[NL802154_ATTR_SCAN_TYPE]) {
>  		NL_SET_ERR_MSG(info->extack, "Malformed request, missing scan type");
>  		return -EINVAL;
>  	}

Thanks,
Miquèl