Go to file
David S. Miller 4884ddba7f Merge branch 'tcp-md5-vrf-fix'
Leonard Crestez says:

====================
tcp: md5: Fix overlap between vrf and non-vrf keys

With net.ipv4.tcp_l3mdev_accept=1 it is possible for a listen socket to
accept connection from the same client address in different VRFs. It is
also possible to set different MD5 keys for these clients which differ only
in the tcpm_l3index field.

This appears to work when distinguishing between different VRFs but not
between non-VRF and VRF connections. In particular:

* tcp_md5_do_lookup_exact will match a non-vrf key against a vrf key. This
means that adding a key with l3index != 0 after a key with l3index == 0
will cause the earlier key to be deleted. Both keys can be present if the
non-vrf key is added later.
* _tcp_md5_do_lookup can match a non-vrf key before a vrf key. This casues
failures if the passwords differ.

This can be fixed by making tcp_md5_do_lookup_exact perform an actual exact
comparison on l3index and by making  __tcp_md5_do_lookup perfer vrf-bound
keys above other considerations like prefixlen.

The fact that keys with l3index==0 affect VRF connections is usually not
desirable, VRFs are meant to be completely independent. This behavior needs
to preserved for backwards compatibility. Also, applications can just bind
listen sockets to VRF and never specify TCP_MD5SIG_FLAG_IFINDEX at all.

So far the combination of TCP_MD5SIG_FLAG_IFINDEX with tcpm_ifindex == 0
was an error, accept this to mean "key only applies to default VRF". This
is what applications using VRFs for traffic separation want.

This also contains tests for the second part. It does not contain tests for
overlapping keys, that would require more changes in nettest to add
multiple keys. These scenarios are also covered by my tests for TCP-AO,
especially around this area:
https://github.com/cdleonard/tcp-authopt-test/blob/main/tcp_authopt_test/test_vrf_bind.py

Changes since V2:
* Rename --do-bind-key-ifindex to --force-bind-key-ifindex
* Fix referencing TCP_MD5SIG_FLAG_IFINDEX as TCP_MD5SIG_IFINDEX
Link to v2: https://lore.kernel.org/netdev/cover.1634107317.git.cdleonard@gmail.com/

Changes since V1:
* Accept (TCP_MD5SIG_IFINDEX with tcpm_ifindex == 0)
* Add flags for explicitly including or excluding TCP_MD5SIG_FLAG_IFINDEX
to nettest
* Add few more tests in fcnal-test.sh.
Link to v1: https://lore.kernel.org/netdev/3d8387d499f053dba5cd9184c0f7b8445c4470c6.1633542093.git.cdleonard@gmail.com/
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-10-15 14:36:57 +01:00
arch Networking fixes for 5.15-rc6. 2021-10-14 18:21:39 -04:00
block block-5.15-2021-10-09 2021-10-09 14:51:59 -07:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2021-08-30 12:57:10 -07:00
Documentation Networking fixes for 5.15-rc6. 2021-10-14 18:21:39 -04:00
drivers lan78xx: select CRC32 2021-10-15 14:34:35 +01:00
fs for-5.15-rc5-tag 2021-10-11 16:48:19 -07:00
include tcp: md5: Allow MD5SIG_FLAG_IFINDEX with ifindex=0 2021-10-15 14:36:57 +01:00
init Merge branch 'work.init' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-09-24 10:18:07 -07:00
ipc ipc: remove memcg accounting for sops objects in do_semtimedop() 2021-09-14 10:22:11 -07:00
kernel Modules fix for v5.15-rc6 2021-10-13 07:42:07 -07:00
lib linux-kselftest-kunit-fixes-5.15-rc6 2021-10-11 17:25:08 -07:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm mm: fix uninitialized use in overcommit_policy_handler 2021-09-24 16:13:35 -07:00
net tcp: md5: Allow MD5SIG_FLAG_IFINDEX with ifindex=0 2021-10-15 14:36:57 +01:00
samples samples/bpf: Relicense bpf_insn.h as GPL-2.0-only OR BSD-2-Clause 2021-09-29 16:03:55 +02:00
scripts linux-kselftest-kunit-fixes-5.15-rc6 2021-10-11 17:25:08 -07:00
security Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ 2021-10-07 12:44:41 +01:00
sound ALSA: usb-audio: Add quirk for VF0770 2021-10-12 22:13:11 +02:00
tools selftests: net/fcnal: Test --{force,no}-bind-key-ifindex 2021-10-15 14:36:57 +01:00
usr .gitignore: prefix local generated files with a slash 2021-05-02 00:43:35 +09:00
virt KVM: Remove tlbs_dirty 2021-09-23 11:01:12 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.cocciconfig
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap mailmap: update email address of Matthias Fuchs and Thomas Körper 2021-08-19 09:39:44 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Networking fixes for 5.15-rc6. 2021-10-14 18:21:39 -04:00
Makefile Linux 5.15-rc5 2021-10-10 17:01:59 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.