No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Toshiaki Makita 4bbb3e0e82 net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off
When we have a bridge with vlan_filtering on and a vlan device on top of
it, packets would be corrupted in skb_vlan_untag() called from
br_dev_xmit().

The problem sits in skb_reorder_vlan_header() used in skb_vlan_untag(),
which makes use of skb->mac_len. In this function mac_len is meant for
handling rx path with vlan devices with reorder_header disabled, but in
tx path mac_len is typically 0 and cannot be used, which is the problem
in this case.

The current code even does not properly handle rx path (skb_vlan_untag()
called from __netif_receive_skb_core()) with reorder_header off actually.

In rx path single tag case, it works as follows:

- Before skb_reorder_vlan_header()

 mac_header                                data
   v                                        v
   +-------------------+-------------+------+----
   |        ETH        |    VLAN     | ETH  |
   |       ADDRS       | TPID | TCI  | TYPE |
   +-------------------+-------------+------+----
   <-------- mac_len --------->
                       <------------->
                        to be removed

- After skb_reorder_vlan_header()

            mac_header                     data
                 v                          v
                 +-------------------+------+----
                 |        ETH        | ETH  |
                 |       ADDRS       | TYPE |
                 +-------------------+------+----
                 <-------- mac_len --------->

This is ok, but in rx double tag case, it corrupts packets:

- Before skb_reorder_vlan_header()

 mac_header                                              data
   v                                                      v
   +-------------------+-------------+-------------+------+----
   |        ETH        |    VLAN     |    VLAN     | ETH  |
   |       ADDRS       | TPID | TCI  | TPID | TCI  | TYPE |
   +-------------------+-------------+-------------+------+----
   <--------------- mac_len ---------------->
                                     <------------->
                                    should be removed
                       <--------------------------->
                         actually will be removed

- After skb_reorder_vlan_header()

            mac_header                                   data
                 v                                        v
                               +-------------------+------+----
                               |        ETH        | ETH  |
                               |       ADDRS       | TYPE |
                               +-------------------+------+----
                 <--------------- mac_len ---------------->

So, two of vlan tags are both removed while only inner one should be
removed and mac_header (and mac_len) is broken.

skb_vlan_untag() is meant for removing the vlan header at (skb->data - 2),
so use skb->data and skb->mac_header to calculate the right offset.

Reported-by: Brandon Carpenter <brandon.carpenter@cypherpath.com>
Fixes: a6e18ff111 ("vlan: Fix untag operations of stacked vlans with REORDER_HEADER off")
Signed-off-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-16 10:03:47 -04:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-03-07 20:27:51 -05:00
block for-linus-20180302 2018-03-02 09:35:36 -08:00
certs certs/blacklist_nohashes.c: fix const confusion in certs blacklist 2018-02-21 15:35:43 -08:00
crypto X.509: fix NULL dereference when restricting key with unsupported_sig 2018-02-22 14:38:34 +00:00
Documentation net: use skb_is_gso_sctp() instead of open-coding 2018-03-09 11:41:47 -05:00
drivers sunvnet: does not support GSO for sctp 2018-03-14 14:01:33 -04:00
firmware
fs for-4.16-rc3-tag 2018-03-04 11:04:27 -08:00
include net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off 2018-03-16 10:03:47 -04:00
init jump_label: Explicitly disable jump labels in __init code 2018-02-21 16:54:05 +01:00
ipc vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-05 11:29:24 -08:00
lib test_rhashtable: add test case for rhltable with duplicate objects 2018-03-07 10:44:03 -05:00
LICENSES
mm mm: don't defer struct page initialization for Xen pv guests 2018-02-21 15:35:43 -08:00
net net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off 2018-03-16 10:03:47 -04:00
samples - do not build samples when cross compiling (Michal Hocko) 2018-02-27 10:39:29 -08:00
scripts Kbuild fixes for v4.16 2018-03-03 10:37:01 -08:00
security integrity/security: fix digsig.c build error with header file 2018-02-22 20:09:08 -08:00
sound ALSA: x86: Fix potential crash at error path 2018-02-28 08:46:00 +01:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf 2018-03-07 20:27:51 -05:00
usr
virt KVM: mmu: Fix overlap between public and private memslots 2018-02-24 01:43:36 +01:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore .gitignore: ignore ASN.1 auto generated files 2018-02-14 21:05:38 +01:00
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS Kbuild fixes for v4.16 2018-03-03 10:37:01 -08:00
Makefile Linux 4.16-rc4 2018-03-04 14:54:11 -08:00
README

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

This file was moved to Documentation/admin-guide/README.rst

Please notice that there are several guides for kernel developers and users.
These guides can be rendered in a number of formats, like HTML and PDF.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

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.