linux-stable.git/net/ipv6/route.c, branch linux-5.2.y

ipv6: addrconf_f6i_alloc - fix non-null pointer check to !IS_ERR()

2019-09-19T07:10:49+00:00

[ Upstream commit 8652f17c658d03f5c87b8dee6e8e52480c6cd37d ]

Fixes a stupid bug I recently introduced...
ip6_route_info_create() returns an ERR_PTR(err) and not a NULL on error.

Fixes: d55a2e374a94 ("net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)'")
Cc: David Ahern 
Cc: Lorenzo Colitti 
Cc: Eric Dumazet 
Signed-off-by: Maciej Żenczykowski 
Reported-by: syzbot 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net-ipv6: fix excessive RTF_ADDRCONF flag on ::1/128 local route (and others)

2019-09-19T07:10:48+00:00

[ Upstream commit d55a2e374a94fa34a3048c6a2be535266e506d97 ]

There is a subtle change in behaviour introduced by:
  commit c7a1ce397adacaf5d4bb2eab0a738b5f80dc3e43
  'ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create'

Before that patch /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000003 00000000 80200001 lo

Afterwards /proc/net/ipv6_route includes:
00000000000000000000000000000001 80 00000000000000000000000000000000 00 00000000000000000000000000000000 00000000 00000002 00000000 80240001 lo

ie. the above commit causes the ::1/128 local (automatic) route to be flagged with RTF_ADDRCONF (0x040000).

AFAICT, this is incorrect since these routes are *not* coming from RA's.

As such, this patch restores the old behaviour.

Fixes: c7a1ce397ada ("ipv6: Change addrconf_f6i_alloc to use ip6_route_info_create")
Cc: David Ahern 
Cc: Lorenzo Colitti 
Signed-off-by: Maciej Żenczykowski 
Reviewed-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: rt6_check should return NULL if 'from' is NULL

2019-07-28T06:27:12+00:00

[ Upstream commit 49d05fe2c9d1b4a27761c9807fec39b8155bef9e ]

Paul reported that l2tp sessions were broken after the commit referenced
in the Fixes tag. Prior to this commit rt6_check returned NULL if the
rt6_info 'from' was NULL - ie., the dst_entry was disconnected from a FIB
entry. Restore that behavior.

Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes")
Reported-by: Paul Donohue 
Tested-by: Paul Donohue 
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ipv6: fix neighbour resolution with raw socket

2019-06-26T20:26:08+00:00

The scenario is the following: the user uses a raw socket to send an ipv6
packet, destinated to a not-connected network, and specify a connected nh.
Here is the corresponding python script to reproduce this scenario:

 import socket
 IPPROTO_RAW = 255
 send_s = socket.socket(socket.AF_INET6, socket.SOCK_RAW, IPPROTO_RAW)
 # scapy
 # p = IPv6(src='fd00:100::1', dst='fd00:200::fa')/ICMPv6EchoRequest()
 # str(p)
 req = b'`\x00\x00\x00\x00\x08:@\xfd\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\xfd\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xfa\x80\x00\x81\xc0\x00\x00\x00\x00'
 send_s.sendto(req, ('fd00:175::2', 0, 0, 0))

fd00:175::/64 is a connected route and fd00:200::fa is not a connected
host.

With this scenario, the kernel starts by sending a NS to resolve
fd00:175::2. When it receives the NA, it flushes its queue and try to send
the initial packet. But instead of sending it, it sends another NS to
resolve fd00:200::fa, which obvioulsy fails, thus the packet is dropped. If
the user sends again the packet, it now uses the right nh (fd00:175::2).

The problem is that ip6_dst_lookup_neigh() uses the rt6i_gateway, which is
:: because the associated route is a connected route, thus it uses the dst
addr of the packet. Let's use rt6_nexthop() to choose the right nh.

Signed-off-by: Nicolas Dichtel 
Signed-off-by: David S. Miller

net/ipv6: Fix misuse of proc_dointvec "skip_notify_on_dev_down"

2019-06-25T19:59:04+00:00

/proc/sys/net/ipv6/route/skip_notify_on_dev_down assumes given value to be
0 or 1. Use proc_dointvec_minmax instead of proc_dointvec.

Fixes: 7c6bb7d2faaf ("net/ipv6: Add knob to skip DELROUTE message ondevice down")
Signed-off-by: Eiichi Tsukata 
Signed-off-by: David S. Miller

ipv6: Default fib6_type to RTN_UNICAST when not set

2019-06-19T21:14:05+00:00

A user reported that routes are getting installed with type 0 (RTN_UNSPEC)
where before the routes were RTN_UNICAST. One example is from accel-ppp
which apparently still uses the ioctl interface and does not set
rtmsg_type. Another is the netlink interface where ipv6 does not require
rtm_type to be set (v4 does). Prior to the commit in the Fixes tag the
ipv6 stack converted type 0 to RTN_UNICAST, so restore that behavior.

Fixes: e8478e80e5a7 ("net/ipv6: Save route type in rt6_info")
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

Merge tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2019-05-31T15:34:32+00:00

Pull yet more SPDX updates from Greg KH:
 "Here is another set of reviewed patches that adds SPDX tags to
  different kernel files, based on a set of rules that are being used to
  parse the comments to try to determine that the license of the file is
  "GPL-2.0-or-later" or "GPL-2.0-only". Only the "obvious" versions of
  these matches are included here, a number of "non-obvious" variants of
  text have been found but those have been postponed for later review
  and analysis.

  There is also a patch in here to add the proper SPDX header to a bunch
  of Kbuild files that we have missed in the past due to new files being
  added and forgetting that Kbuild uses two different file names for
  Makefiles. This issue was reported by the Kbuild maintainer.

  These patches have been out for review on the linux-spdx@vger mailing
  list, and while they were created by automatic tools, they were
  hand-verified by a bunch of different people, all whom names are on
  the patches are reviewers"

* tag 'spdx-5.2-rc3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (82 commits)
  treewide: Add SPDX license identifier - Kbuild
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 225
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 224
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 223
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 222
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 221
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 220
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 218
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 217
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 216
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 215
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 214
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 213
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 211
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 210
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 209
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 207
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 206
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 203
  treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 201
  ...

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

2019-05-30T18:26:32+00:00

Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman

ipv6: Fix redirect with VRF

2019-05-23T00:58:21+00:00

IPv6 redirect is broken for VRF. __ip6_route_redirect walks the FIB
entries looking for an exact match on ifindex. With VRF the flowi6_oif
is updated by l3mdev_update_flow to the l3mdev index and the
FLOWI_FLAG_SKIP_NH_OIF set in the flags to tell the lookup to skip the
device match. For redirects the device match is requires so use that
flag to know when the oif needs to be reset to the skb device index.

Fixes: ca254490c8df ("net: Add VRF support to IPv6 stack")
Signed-off-by: David Ahern 
Signed-off-by: David S. Miller

ipv6: fix src addr routing with the exception table

2019-05-16T21:30:53+00:00

When inserting route cache into the exception table, the key is
generated with both src_addr and dest_addr with src addr routing.
However, current logic always assumes the src_addr used to generate the
key is a /128 host address. This is not true in the following scenarios:
1. When the route is a gateway route or does not have next hop.
   (rt6_is_gw_or_nonexthop() == false)
2. When calling ip6_rt_cache_alloc(), saddr is passed in as NULL.
This means, when looking for a route cache in the exception table, we
have to do the lookup twice: first time with the passed in /128 host
address, second time with the src_addr stored in fib6_info.

This solves the pmtu discovery issue reported by Mikael Magnusson where
a route cache with a lower mtu info is created for a gateway route with
src addr. However, the lookup code is not able to find this route cache.

Fixes: 2b760fcf5cfb ("ipv6: hook up exception table to store dst cache")
Reported-by: Mikael Magnusson 
Bisected-by: David Ahern 
Signed-off-by: Wei Wang 
Cc: Martin Lau 
Cc: Eric Dumazet 
Acked-by: Martin KaFai Lau 
Signed-off-by: David S. Miller