netdev - Re: [PATCH net-next v2 1/6] net: dcb: add new pcp selector to app object

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20221004125147.7f76d409@kernel.org>
Date:   Tue, 4 Oct 2022 12:51:47 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Petr Machata <petrm@...dia.com>
Cc:     Daniel Machon <daniel.machon@...rochip.com>,
        <netdev@...r.kernel.org>, <davem@...emloft.net>,
        <maxime.chevallier@...tlin.com>, <thomas.petazzoni@...tlin.com>,
        <edumazet@...gle.com>, <pabeni@...hat.com>,
        <lars.povlsen@...rochip.com>, <Steen.Hegelund@...rochip.com>,
        <UNGLinuxDriver@...rochip.com>, <joe@...ches.com>,
        <linux@...linux.org.uk>, <horatiu.vultur@...rochip.com>,
        <Julia.Lawall@...ia.fr>, <vladimir.oltean@....com>,
        <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH net-next v2 1/6] net: dcb: add new pcp selector to app
 object

On Tue, 4 Oct 2022 12:52:35 +0200 Petr Machata wrote:
> > The question is whether it's better to do it anyway. My opinion is that
> > if a userspace decides to make assumptions about the contents of a TLV,
> > and neglects to validate the actual TLV type, it's on them, and I'm not
> > obligated to keep them working. We know about this case, but really any
> > attribute addition at all could potentially trip some userspace if they
> > expected something else at this offset.  
> 
> And re the flag: I think struct dcbmsg.dcb_pad was meant to be the place
> to keep flags when the need arises, but it is not validated anywhere, so
> we cannot use it. It could be a new command, but I'm not a fan. So if we
> need to discriminate userspaces, I think it should be a new attribute.

All good points. I'm fine with not gating the attributes if that's your
preference. Your call.