From: Stephen Hemminger <stephen@networkplumber•org>
To: Linus Torvalds <torvalds@linux-foundation•org>
Cc: Andy Lutomirski <luto@amacapital•net>,
David Miller <davem@davemloft•net>,
"Jorge Boncompte [DTI2]" <jorge@dti2•net>,
"Eric W. Biederman" <ebiederm@xmission•com>,
Vivek Goyal <vgoyal@redhat•com>, Simo Sorce <ssorce@redhat•com>,
"security@kernel•org" <security@kernel•org>,
Network Development <netdev@vger•kernel.org>,
"Serge E. Hallyn" <serge@hallyn•com>
Subject: Re: [PATCH 5/5] net: Use netlink_ns_capable to verify the permisions of netlink messages
Date: Thu, 8 May 2014 14:29:39 -0700 [thread overview]
Message-ID: <20140508142939.201b3e07@nehalam.linuxnetplumber.net> (raw)
In-Reply-To: <CA+55aFzZg3LfpPpx3+83sB0npd9863NTMqvsCArMDjg-9J151A@mail.gmail.com>
On Wed, 7 May 2014 16:34:08 -0700
Linus Torvalds <torvalds@linux-foundation•org> wrote:
> On Wed, May 7, 2014 at 4:01 PM, Andy Lutomirski <luto@amacapital•net> wrote:
> >
> > I agree that it should, but it doesn't, and if these patches get
> > backported, things will break. OTOH, if the patches don't get
> > backported, things may still break, and we have a possibly rather
> > severe unfixed vulnerability.
>
> How did this *use* to work? It looks like it drops permissions after
> the bind(), so the actual _IO_ must have always been done without
> permissions, no?
>
> Is it just a bind-time permission check that is now failing, because
> it uses the credentials associated with the socket open? If so, I'd
> suggest unding just the ns-capable change for bind(), and make that
> one always use the current process effective one.
>
> If you're a suid application, you're not doing "bind()" on random file
> descriptors that were passed to you. It's really just read/write that
> need to be careful.
>
> Linus
Quagga drops privileges at startup then selectively raises them.
The code is doing raise caps in netlink code for bind and each sendto
and recvmsg call.
Ideally it should be able to not have to raise/lower on each send/recvmsg
call.
next prev parent reply other threads:[~2014-05-08 21:29 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CALCETrUaYhh6Dkzn0TMEUz-GEO9-6ObByk5d_xRViSMBbp5Pkg@mail.gmail.com>
[not found] ` <cover.1397840611.git.luto@amacapital.net>
[not found] ` <6daf425e2023266d52d181e4d2ee18747d4f1fa8.1397840611.git.luto@amacapital.net>
[not found] ` <87tx9nuxf6.fsf@x220.int.ebiederm.org>
[not found] ` <CALCETrUqNVRBse4rUeUKfgYt0d+9x1JrEHGcZ_DnWyq7W6Yyzw@mail.gmail.com>
[not found] ` <87r44qtabz.fsf@x220.int.ebiederm.org>
[not found] ` <CALCETrWzUQ7QjykT85ExDfX-+9eDD-D-dcxofUMPvLK=ia9arg@mail.gmail.com>
[not found] ` <87r44qrt8v.fsf_-_@x220.int.ebiederm.org>
2014-04-22 21:13 ` [PATCH 0/6]: Preventing abuse when passing file descriptors Eric W. Biederman
2014-04-22 21:14 ` [PATCH 1/6] netlink: Rename netlink_capable netlink_allowed Eric W. Biederman
2014-04-22 21:15 ` [PATCH 2/6] net: Move the permission check in sock_diag_put_filterinfo to packet_diag_dump Eric W. Biederman
2014-04-22 21:15 ` [PATCH 3/6] net: Fix ns_capable check in packet_diag_dump Eric W. Biederman
2014-04-22 21:16 ` [PATCH 4/6] net: Add variants of capable for use on on sockets Eric W. Biederman
2014-04-22 21:16 ` [PATCH 5/6] net: Add variants of capable for use on netlink messages Eric W. Biederman
2014-04-22 21:17 ` [PATCH 6/6] net: Use netlink_ns_capable to verify the permisions of " Eric W. Biederman
2014-04-23 19:32 ` [PATCH 0/6]: Preventing abuse when passing file descriptors David Miller
2014-04-23 21:24 ` [PATCH 0/5]: " Eric W. Biederman
2014-04-23 21:25 ` [PATCH 1/5] netlink: Rename netlink_capable netlink_allowed Eric W. Biederman
2014-04-23 21:26 ` [PATCH 2/5] net: Move the permission check in sock_diag_put_filterinfo to packet_diag_dump Eric W. Biederman
2014-04-23 21:26 ` [PATCH 3/5] net: Add variants of capable for use on on sockets Eric W. Biederman
2014-04-23 21:28 ` [PATCH 4/5] net: Add variants of capable for use on netlink messages Eric W. Biederman
2014-04-23 21:29 ` [PATCH 5/5] net: Use netlink_ns_capable to verify the permisions of " Eric W. Biederman
2014-05-07 22:18 ` Jorge Boncompte [DTI2]
2014-05-07 22:26 ` Andy Lutomirski
2014-05-07 22:52 ` David Miller
2014-05-07 23:01 ` Andy Lutomirski
2014-05-07 23:34 ` Linus Torvalds
2014-05-07 23:45 ` Andy Lutomirski
2014-05-22 15:05 ` Jiri Benc
2014-05-23 23:25 ` Eric W. Biederman
2014-05-23 23:51 ` Linus Torvalds
2014-05-24 22:34 ` David Miller
2014-05-25 5:38 ` [RFC][PATCH] netlink: Only check file credentials for implicit destinations Eric W. Biederman
2014-05-25 16:50 ` Andy Lutomirski
2014-05-25 23:44 ` Eric W. Biederman
2014-05-26 0:32 ` Linus Torvalds
2014-05-26 5:36 ` [RFC][PATCH 2/1] netlink: Use the credential at the time the destination address was set Eric W. Biederman
2014-05-26 17:19 ` Andy Lutomirski
2014-05-27 4:24 ` Eric W. Biederman
2014-05-26 13:39 ` [RFC][PATCH] netlink: Only check file credentials for implicit destinations Willy Tarreau
2014-05-26 8:38 ` Michael Kerrisk (man-pages)
2014-05-25 5:45 ` [PATCH 5/5] net: Use netlink_ns_capable to verify the permisions of netlink messages Eric W. Biederman
2014-05-25 16:27 ` Andy Lutomirski
2014-05-08 21:29 ` Stephen Hemminger [this message]
2014-05-08 21:32 ` Andy Lutomirski
[not found] ` <CA+55aFzOHZcw2o6Cq6rSddSBDZvhgzYToBruak9SLCHxx-fA3Q@mail.gmail.com>
2014-05-08 21:49 ` Andy Lutomirski
2014-05-08 22:07 ` Stephen Hemminger
2014-05-08 21:54 ` David Miller
2014-05-07 23:45 ` David Miller
2014-05-08 21:21 ` Stephen Hemminger
2014-05-08 21:52 ` David Miller
2014-05-08 21:54 ` Andy Lutomirski
2014-04-24 17:45 ` [PATCH 0/5]: Preventing abuse when passing file descriptors David Miller
2014-06-13 1:31 [PATCH 0/5] Backport to 3.10.y for fix CVE-2014-0181 Xiangyu Lu
2014-06-13 1:31 ` [PATCH 5/5] net: Use netlink_ns_capable to verify the permisions of netlink messages Xiangyu Lu
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