netdev - Re: [PATCH net] pktgen: do not sleep with the thread lock held.

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 for Android: free password hash cracker in your pocket

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

Date:   Thu, 06 Jun 2019 10:27:10 +0200
From:   Paolo Abeni <pabeni@...hat.com>
To:     David Miller <davem@...emloft.net>
Cc:     netdev@...r.kernel.org, mcroce@...hat.com
Subject: Re: [PATCH net] pktgen: do not sleep with the thread lock held.

Hi,

Thank you for the feedback.

On Wed, 2019-06-05 at 12:05 -0700, David Miller wrote:
> From: Paolo Abeni <pabeni@...hat.com>
> Date: Wed,  5 Jun 2019 14:34:46 +0200
> 
> > @@ -3062,20 +3062,49 @@ static int thread_is_running(const struct pktgen_thread *t)
> >       return 0;
> >  }
> >  
> > -static int pktgen_wait_thread_run(struct pktgen_thread *t)
> > +static bool pktgen_lookup_thread(struct pktgen_net *pn, struct pktgen_thread *t)
> > +{
> > +     struct pktgen_thread *tmp;
> > +
> > +     list_for_each_entry(tmp, &pn->pktgen_threads, th_list)
> > +             if (tmp == t)
> > +                     return true;
> > +     return false;
> > +}
> 
> Pointer equality is not object equality.

Indeed. The trick is that pktgen threads are allocated only at net
creation time.

Actaully they are also freed only net exit, so the extra care is not
needed: the current process held a reference to net via fs proxy.

I'll send a v2 cleaning up the unneeded parts and some documenting
comments.

Cheers,

Paolo