Re: [PATCH v1 net-next] ila: avoid genlmsg_reply when not ila_map found

[Lin Ma]

Hi Simon.

> 
> Hi Lin Ma,
> 
> The lines immediately above those covered by this patch are as follows:
> 
> 	ret = -ESRCH;
> 	ila = ila_lookup_by_params(&xp, ilan);
> 	if (ila) {
> 		ret = ila_dump_info(ila,
> 
> > @@ -483,6 +483,8 @@ int ila_xlat_nl_cmd_get_mapping(struct sk_buff *skb, struct genl_info *info)
> >  				    info->snd_portid,
> >  				    info->snd_seq, 0, msg,
> >  				    info->genlhdr->cmd);
> > +	} else {
> > +		ret = -EINVAL;
> >  	}
> >  
> >  	rcu_read_unlock();
> 
> And the lines following, up to the end of the function, are:
> 
> 	if (ret < 0)
> 		goto out_free;
> 
> 	return genlmsg_reply(msg, info);
> 
> out_free:
> 	nlmsg_free(msg);
> 	return ret;
> 
> By my reading, without your patch, if ila is not found (NULL)
> then ret will be -ESRCH, and genlmsg_reply will not be called.
> 
> I feel that I am missing something here.

Oh my bad, it seems this bug was already fixed by the
commit 693aa2c0d9b6 ("ila: do not generate empty messages
in ila_xlat_nl_cmd_get_mapping()") last year.
And my dated kernel does not apply that one.

Thanks for reminding me of this false alarm.

Regards
Lin