Subject: Re: [PATCH][next] batman-adv: don't pass a NULL hard_iface to batadv_hardif_put

From: Simon Wunderlich <[email-masked]>
Date: Mon, 26 Mar 2018 14:57:02 +0200

Hi,

this looks good. David, would you pick this patch directly? Otherwise, I can 
send a pull request, but right now we would only have this single patch for 
net-next.

Acked-by: Simon Wunderlich <[email-masked]>
Acked-by: Sven Eckelmann <[email-masked]>

(just discussed with Sven offline)

Thank you,
     Simon

On Friday, March 23, 2018 10:53:50 PM CEST Colin King wrote:
> From: Colin Ian King <[email-masked]>
> 
> In the case where hard_iface is NULL, the error path may pass a null
> pointer to batadv_hardif_put causing a null pointer dereference error.
> Avoid this by only calling the function if  hard_iface not null.
> 
> Detected by CoverityScan, CID#1466456 ("Explicit null dereferenced")
> 
> Fixes: 53dd9a68ba68 ("batman-adv: add multicast flags netlink support")
> Signed-off-by: Colin Ian King <[email-masked]>
> ---
>  net/batman-adv/multicast.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c
> index de3a055f7dd8..bd0ea374d043 100644
> --- a/net/batman-adv/multicast.c
> +++ b/net/batman-adv/multicast.c
> @@ -1536,7 +1536,7 @@ batadv_mcast_netlink_get_primary(struct
> netlink_callback *cb,
> 
>  	if (!ret && primary_if)
>  		*primary_if = hard_iface;
> -	else
> +	else if (hard_iface)
>  		batadv_hardif_put(hard_iface);
> 
>  	return ret;