netdev - Re: [Patch net-next] net: introduce a knob to control whether to inherit devconf config

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: <CAMDZJNXHvZSEs-PT9=MJjJRV1iKeOazj4uFBFOEZBgVbP_tJgA@mail.gmail.com>
Date:   Fri, 18 Jan 2019 22:38:35 +0800
From:   Tonghao Zhang <xiangxia.m.yue@...il.com>
To:     Nicolas Dichtel <nicolas.dichtel@...nd.com>
Cc:     Cong Wang <xiyou.wangcong@...il.com>,
        Linux Kernel Network Developers <netdev@...r.kernel.org>,
        Zhu Yanjun <Yanjun.Zhu@...driver.com>
Subject: Re: [Patch net-next] net: introduce a knob to control whether to
 inherit devconf config

On Fri, Jan 18, 2019 at 4:25 PM Nicolas Dichtel
<nicolas.dichtel@...nd.com> wrote:
>
> Le 18/01/2019 à 08:27, Cong Wang a écrit :
> > There have been many people complaining about the inconsistent
> > behaviors of IPv4 and IPv6 devconf when creating new network
> > namespaces.  Currently, for IPv4, we inherit all current settings
> > from init_net, but for IPv6 we reset all setting to default.
> >
> > This patch introduces a new /proc file
> > /proc/sys/net/core/devconf_inherit_init_net to control the
> > behavior of whether to inhert sysctl current settings from init_net.
> > This file itself is only available in init_net.
> >
> > As demonstrated below:
> >
> > Initial setup in init_net:
> >  # cat /proc/sys/net/ipv4/conf/all/rp_filter
> >  2
> >  # cat /proc/sys/net/ipv6/conf/all/accept_dad
> >  1
> >
> > Default value 0 (current behavior):
> >  # ip netns del test
> >  # ip netns add test
> >  # ip netns exec test cat /proc/sys/net/ipv4/conf/all/rp_filter
> >  2
> >  # ip netns exec test cat /proc/sys/net/ipv6/conf/all/accept_dad
> >  0
> >
> > Set to 1 (inherit from init_net):
> >  # echo 1 > /proc/sys/net/core/devconf_inherit_init_net
> >  # ip netns del test
> >  # ip netns add test
> >  # ip netns exec test cat /proc/sys/net/ipv4/conf/all/rp_filter
> >  2
> >  # ip netns exec test cat /proc/sys/net/ipv6/conf/all/accept_dad
> >  1
> >
> > Set to 2 (reset to default):
> >  # echo 2 > /proc/sys/net/core/devconf_inherit_init_net
> >  # ip netns del test
> >  # ip netns add test
> >  # ip netns exec test cat /proc/sys/net/ipv4/conf/all/rp_filter
> >  0
> >  # ip netns exec test cat /proc/sys/net/ipv6/conf/all/accept_dad
> >  0
> >
> > Set to a value out of range (invalid):
> >  # echo 3 > /proc/sys/net/core/devconf_inherit_init_net
> >  -bash: echo: write error: Invalid argument
> >  # echo -1 > /proc/sys/net/core/devconf_inherit_init_net
> >  -bash: echo: write error: Invalid argument
> >
> > Reported-by: Zhu Yanjun <Yanjun.Zhu@...driver.com>
> > Reported-by: Tonghao Zhang <xiangxia.m.yue@...il.com>
> > Cc: Nicolas Dichtel <nicolas.dichtel@...nd.com>
> > Signed-off-by: Cong Wang <xiyou.wangcong@...il.com>
> Nice!
>
> Acked-by: Nicolas Dichtel <nicolas.dichtel@...nd.com>
Acked-by: Tonghao Zhang <xiangxia.m.yue@...il.com>