netdev - Re: [PATCH net-next 1/4] netns: don't clear nsid too early on removal

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: <551E63B9.9050208@6wind.com>
Date:	Fri, 03 Apr 2015 11:56:09 +0200
From:	Nicolas Dichtel <nicolas.dichtel@...nd.com>
To:	"Eric W. Biederman" <ebiederm@...ssion.com>
CC:	netdev@...r.kernel.org, davem@...emloft.net
Subject: Re: [PATCH net-next 1/4] netns: don't clear nsid too early on removal

Le 02/04/2015 20:51, Eric W. Biederman a écrit :
[snip]
>
> There should be no network sockets and thus no in flight rtnl traffic at
> the time cleanup_net is metioned so I don't see how this patch fixes
> the mentioned commit.
Yes and no.
Yes, there is no network sockets into this netns, *but* modules build
netlink messages because they don't know if there are listeners or not.

>
> I have a second issue with the fact that the code is unnecessarily
> quadratic.  We should keep a list of the issues netns ids and just
> revoke them instead of walking the whole network namespaces.
>
> I strongly suspect that this change makes it possible to create a
> network device whose bottom is in a network namespace we are destroying
> after we have destroyed all of the network devices in that namespace and
> otherwise cleaned up.   Beyond that I can not reason about this patch
> because it opens up a huge number of races.
Ok, you're probably right.
I will send an update.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html