netdev - Re: [PATCH net 1/2] ipv6: Dump route exceptions too in rt6_dump

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: <20190608054003.5uwggebuawjtetyg@kafai-mbp.dhcp.thefacebook.com>
Date:   Sat, 8 Jun 2019 05:40:06 +0000
From:   Martin Lau <kafai@...com>
To:     David Ahern <dsahern@...il.com>
CC:     Stefano Brivio <sbrivio@...hat.com>,
        David Miller <davem@...emloft.net>,
        Jianlin Shi <jishi@...hat.com>, Wei Wang <weiwan@...gle.com>,
        Eric Dumazet <edumazet@...gle.com>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>
Subject: Re: [PATCH net 1/2] ipv6: Dump route exceptions too in
 rt6_dump_route()

On Thu, Jun 06, 2019 at 04:47:00PM -0600, David Ahern wrote:
> On 6/6/19 3:18 PM, Stefano Brivio wrote:
> > On Thu, 6 Jun 2019 14:57:33 -0600
> > David Ahern <dsahern@...il.com> wrote:
> > 
> >>> This will cause a non-trivial conflict with commit cc5c073a693f
> >>> ("ipv6: Move exception bucket to fib6_nh") on net-next. I can submit
> >>> an equivalent patch against net-next, if it helps.
> >>>   
> >>
> >> Thanks for doing this. It is on my to-do list.
> >>
> >> Can you do the same for IPv4?
> > 
> > You mean this same fix? On IPv4, for flushing, iproute2
> > uses /proc/sys/net/ipv4/route/flush in iproute_flush_cache(), and that
> > works.
> > 
> > Listing doesn't work instead, for some different reason I haven't
> > looked into yet. That doesn't look as critical as the situation on IPv6
> > where one can't even flush the cache: exceptions can also be fetched
> > with 'ip route get', and that works.
> > 
> > Still, it's bad, I can look into it within a few days.
> > 
> 
> I meant the ability to dump the exception cache.
> 
> Currently, we do not get the exceptions in a fib dump. There is a flag
> to only show cloned (cached) entries, but no way to say 'no cloned
> entries'. Maybe these should only be dumped if the cloned flag is set.
> That's the use case I was targeting:
> 1. fib dumps - RTM_F_CLONED not set
I also think the fib dump should stay as is.

To be clear, I do not expect exception routes output from the
'ip [-6] r l'.  Otherwise, I will get pages of exceptions
that I am not interested at.  This should apply for both
v4 and v6.

> 2. exception dump - RTM_F_CLONED set