linux-kernel - [PATCH net-next 0/5] rtnetlink: add IFA_IF_NETNSID for RTM

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-next>] [day] [month] [year] [list]

Message-Id: <20180828231859.29758-1-christian@brauner.io>
Date:   Wed, 29 Aug 2018 01:18:54 +0200
From:   Christian Brauner <christian@...uner.io>
To:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Cc:     davem@...emloft.net, kuznet@....inr.ac.ru, yoshfuji@...ux-ipv6.org,
        pombredanne@...b.com, kstewart@...uxfoundation.org,
        gregkh@...uxfoundation.org, dsahern@...il.com, fw@...len.de,
        ktkhai@...tuozzo.com, lucien.xin@...il.com,
        jakub.kicinski@...ronome.com, jbenc@...hat.com,
        nicolas.dichtel@...nd.com,
        Christian Brauner <christian.brauner@...ntu.com>
Subject: [PATCH net-next 0/5] rtnetlink: add IFA_IF_NETNSID for RTM_GETADDR

From: Christian Brauner <christian.brauner@...ntu.com>

Hey,

A while back we introduced and enabled IFLA_IF_NETNSID in
RTM_{DEL,GET,NEW}LINK requests (cf. [1], [2], [3], [4], [5]). This has led
to signficant performance increases since it allows userspace to avoid
taking the hit of a setns(netns_fd, CLONE_NEWNET), then getting the
interfaces from the netns associated with the netns_fd. Especially when a
lot of network namespaces are in use, using setns() becomes increasingly
problematic when performance matters.
Usually, RTML_GETLINK requests are followed by RTM_GETADDR requests (cf.
getifaddrs() style functions and friends). But currently, RTM_GETADDR
requests do not support a similar property like IFLA_IF_NETNSID for
RTM_*LINK requests.
This is problematic since userspace can retrieve interfaces from another
network namespace by sending a IFLA_IF_NETNSID property along but
RTM_GETLINK request but is still forced to use the legacy setns() style of
retrieving interfaces in RTM_GETADDR requests.

The goal of this series is to make it possible to perform RTM_GETADDR
requests on different network namespaces. To this end a new IFA_IF_NETNSID
property for RTM_*ADDR requests is introduced. It can be used to send a
network namespace identifier along in RTM_*ADDR requests.  The network
namespace identifier will be used to retrieve the target network namespace
in which the request is supposed to be fulfilled.  This aligns the behavior
of RTM_*ADDR requests with the behavior of RTM_*LINK requests.

Security:
- The caller must have assigned a valid network namespace identifier for
  the target network namespace.
- The caller must have CAP_NET_ADMIN in the owning user namespace of the
  target network namespace.

Thanks!
Christian

[1]: commit 7973bfd8758d ("rtnetlink: remove check for IFLA_IF_NETNSID")
[2]: commit 5bb8ed075428 ("rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK")
[3]: commit b61ad68a9fe8 ("rtnetlink: enable IFLA_IF_NETNSID for RTM_DELLINK")
[4]: commit c310bfcb6e1b ("rtnetlink: enable IFLA_IF_NETNSID for RTM_SETLINK")
[5]: commit 7c4f63ba8243 ("rtnetlink: enable IFLA_IF_NETNSID in do_setlink()")

Christian Brauner (5):
  rtnetlink: add rtnl_get_net_ns_capable()
  if_addr: add IFA_IF_NETNSID
  ipv4: enable IFA_IF_NETNSID for RTM_GETADDR
  ipv6: enable IFA_IF_NETNSID for RTM_GETADDR
  rtnetlink: move type calculation out of loop

 include/net/rtnetlink.h      |  1 +
 include/uapi/linux/if_addr.h |  1 +
 net/core/rtnetlink.c         | 15 +++++---
 net/ipv4/devinet.c           | 38 +++++++++++++++-----
 net/ipv6/addrconf.c          | 70 ++++++++++++++++++++++++++++--------
 5 files changed, 97 insertions(+), 28 deletions(-)

-- 
2.17.1