netdev - RE: [PATCH 07/17] net: convert sock.sk_refcnt from atomic_t to refcount

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]

Date:   Fri, 17 Mar 2017 07:42:24 +0000
From:   "Reshetova, Elena" <elena.reshetova@...el.com>
To:     David Miller <davem@...emloft.net>,
        "keescook@...omium.org" <keescook@...omium.org>
CC:     "eric.dumazet@...il.com" <eric.dumazet@...il.com>,
        "peterz@...radead.org" <peterz@...radead.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "bridge@...ts.linux-foundation.org" 
        <bridge@...ts.linux-foundation.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "kuznet@....inr.ac.ru" <kuznet@....inr.ac.ru>,
        "jmorris@...ei.org" <jmorris@...ei.org>,
        "kaber@...sh.net" <kaber@...sh.net>,
        "stephen@...workplumber.org" <stephen@...workplumber.org>,
        "ishkamiel@...il.com" <ishkamiel@...il.com>,
        "dwindsor@...il.com" <dwindsor@...il.com>
Subject: RE: [PATCH 07/17] net: convert sock.sk_refcnt from atomic_t to
 refcount_t

> From: Kees Cook <keescook@...omium.org>
> Date: Thu, 16 Mar 2017 11:38:25 -0600
> 
> > I am, of course, biased, but I think the evidence of actual
> > refcounting attacks outweighs the theoretical performance cost of
> > these changes.
> 
> This is not theoretical at all.
> 
> We count the nanoseconds that every packet takes to get processed and
> you are adding quite a bit.
> 
> I understand your point of view, but this is knowingly going to add
> performance regressions to the networking code.

Should we then first measure the actual numbers to understand what we are talking here about? 
I would be glad to do it if you suggest what is the correct way to do measurements here to actually reflect the real life use cases. 

Best Regards,
Elena.