From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Berg Subject: Re: [PATCH 1/2] netlink: add NLA_REJECT policy type Date: Thu, 13 Sep 2018 13:25:15 +0200 Message-ID: <1536837915.4160.1.camel@sipsolutions.net> References: <20180913084603.7979-1-johannes@sipsolutions.net> <20180913104955.GE29691@unicorn.suse.cz> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Michal Kubecek Return-path: In-Reply-To: <20180913104955.GE29691-OEaqT8BN2ewCVLCxKZUutA@public.gmane.org> Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Thu, 2018-09-13 at 12:49 +0200, Michal Kubecek wrote: > > if (type > 0 && type <= maxtype) { > > if (policy) { > > - err = validate_nla(nla, maxtype, policy); > > + err = validate_nla(nla, maxtype, policy, > > + extack); > > if (err < 0) { > > - NL_SET_ERR_MSG_ATTR(extack, nla, > > - "Attribute failed policy validation"); > > + NL_SET_BAD_ATTR(extack, nla); > > + if (extack && !extack->_msg) > > + NL_SET_ERR_MSG(extack, > > + "Attribute failed policy validation"); > > goto errout; > > } > > } > > -- > > Technically, this would change the outcome when nla_parse() is called > with extack->_msg already set nad validate_nla() fails on something else > than NLA_REJECT; it will preserve the previous message in such case. > But I don't think this is a serious problem. Yes, that's true. I looked at quite a few of the setters just now (there are ~500 already, wow!), and they all set & return, so this shouldn't be an issue. johannes