linux-stable.git/net/ipv6, branch v4.9.129

vti6: remove !skb->ignore_df check from vti6_xmit()

2018-09-15T07:42:56+00:00

[ Upstream commit 9f2895461439fda2801a7906fb4c5fb3dbb37a0a ]

Before the commit d6990976af7c ("vti6: fix PMTU caching and reporting
on xmit") '!skb->ignore_df' check was always true because the function
skb_scrub_packet() was called before it, resetting ignore_df to zero.

In the commit, skb_scrub_packet() was moved below, and now this check
can be false for the packet, e.g. when sending it in the two fragments,
this prevents successful PMTU updates in such case. The next attempts
to send the packet lead to the same tx error. Moreover, vti6 initial
MTU value relies on PMTU adjustments.

This issue can be reproduced with the following LTP test script:
    udp_ipsec_vti.sh -6 -p ah -m tunnel -s 2000

Fixes: ccd740cbc6e0 ("vti6: Add pmtu handling to vti6_xmit.")
Signed-off-by: Alexey Kodanev 
Acked-by: Steffen Klassert 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

vti6: fix PMTU caching and reporting on xmit

2018-09-05T07:19:59+00:00

[ Upstream commit d6990976af7c5d8f55903bfb4289b6fb030bf754 ]

When setting the skb->dst before doing the MTU check, the route PMTU
caching and reporting is done on the new dst which is about to be
released.

Instead, PMTU handling should be done using the original dst.

This is aligned with IPv4 VTI.

Fixes: ccd740cbc6 ("vti6: Add pmtu handling to vti6_xmit.")
Signed-off-by: Eyal Birger 
Signed-off-by: Steffen Klassert 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ipv6: make ipv6_renew_options() interrupt/kernel safe

2018-08-24T11:12:36+00:00

[ Upstream commit a9ba23d48dbc6ffd08426bb10f05720e0b9f5c14 ]

At present the ipv6_renew_options_kern() function ends up calling into
access_ok() which is problematic if done from inside an interrupt as
access_ok() calls WARN_ON_IN_IRQ() on some (all?) architectures
(x86-64 is affected).  Example warning/backtrace is shown below:

 WARNING: CPU: 1 PID: 3144 at lib/usercopy.c:11 _copy_from_user+0x85/0x90
 ...
 Call Trace:
  
  ipv6_renew_option+0xb2/0xf0
  ipv6_renew_options+0x26a/0x340
  ipv6_renew_options_kern+0x2c/0x40
  calipso_req_setattr+0x72/0xe0
  netlbl_req_setattr+0x126/0x1b0
  selinux_netlbl_inet_conn_request+0x80/0x100
  selinux_inet_conn_request+0x6d/0xb0
  security_inet_conn_request+0x32/0x50
  tcp_conn_request+0x35f/0xe00
  ? __lock_acquire+0x250/0x16c0
  ? selinux_socket_sock_rcv_skb+0x1ae/0x210
  ? tcp_rcv_state_process+0x289/0x106b
  tcp_rcv_state_process+0x289/0x106b
  ? tcp_v6_do_rcv+0x1a7/0x3c0
  tcp_v6_do_rcv+0x1a7/0x3c0
  tcp_v6_rcv+0xc82/0xcf0
  ip6_input_finish+0x10d/0x690
  ip6_input+0x45/0x1e0
  ? ip6_rcv_finish+0x1d0/0x1d0
  ipv6_rcv+0x32b/0x880
  ? ip6_make_skb+0x1e0/0x1e0
  __netif_receive_skb_core+0x6f2/0xdf0
  ? process_backlog+0x85/0x250
  ? process_backlog+0x85/0x250
  ? process_backlog+0xec/0x250
  process_backlog+0xec/0x250
  net_rx_action+0x153/0x480
  __do_softirq+0xd9/0x4f7
  do_softirq_own_stack+0x2a/0x40
  
  ...

While not present in the backtrace, ipv6_renew_option() ends up calling
access_ok() via the following chain:

  access_ok()
  _copy_from_user()
  copy_from_user()
  ipv6_renew_option()

The fix presented in this patch is to perform the userspace copy
earlier in the call chain such that it is only called when the option
data is actually coming from userspace; that place is
do_ipv6_setsockopt().  Not only does this solve the problem seen in
the backtrace above, it also allows us to simplify the code quite a
bit by removing ipv6_renew_options_kern() completely.  We also take
this opportunity to cleanup ipv6_renew_options()/ipv6_renew_option()
a small amount as well.

This patch is heavily based on a rough patch by Al Viro.  I've taken
his original patch, converted a kmemdup() call in do_ipv6_setsockopt()
to a memdup_user() call, made better use of the e_inval jump target in
the same function, and cleaned up the use ipv6_renew_option() by
ipv6_renew_options().

CC: Al Viro 
Signed-off-by: Paul Moore 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: x_tables: set module owner for icmp(6) matches

2018-08-24T11:12:36+00:00

[ Upstream commit d376bef9c29b3c65aeee4e785fffcd97ef0a9a81 ]

nft_compat relies on xt_request_find_match to increment
refcount of the module that provides the match/target.

The (builtin) icmp matches did't set the module owner so it
was possible to rmmod ip(6)tables while icmp extensions were still in use.

Signed-off-by: Florian Westphal 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ipv6: mcast: fix unsolicited report interval after receiving querys

2018-08-24T11:12:31+00:00

[ Upstream commit 6c6da92808442908287fae8ebb0ca041a52469f4 ]

After recieving MLD querys, we update idev->mc_maxdelay with max_delay
from query header. This make the later unsolicited reports have the same
interval with mc_maxdelay, which means we may send unsolicited reports with
long interval time instead of default configured interval time.

Also as we will not call ipv6_mc_reset() after device up. This issue will
be there even after leave the group and join other groups.

Fixes: fc4eba58b4c14 ("ipv6: make unsolicited report intervals configurable for mld")
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

netfilter: ipv6: nf_defrag: reduce struct net memory waste

2018-08-24T11:12:26+00:00

[ Upstream commit 9ce7bc036ae4cfe3393232c86e9e1fea2153c237 ]

It is a waste of memory to use a full "struct netns_sysctl_ipv6"
while only one pointer is really used, considering netns_sysctl_ipv6
keeps growing.

Also, since "struct netns_frags" has cache line alignment,
it is better to move the frags_hdr pointer outside, otherwise
we spend a full cache line for this pointer.

This saves 192 bytes of memory per netns.

Fixes: c038a767cd69 ("ipv6: add a new namespace for nf_conntrack_reasm")
Signed-off-by: Eric Dumazet 
Signed-off-by: Pablo Neira Ayuso 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

ip6_tunnel: use the right value for ipv4 min mtu check in ip6_tnl_xmit

2018-08-22T05:47:13+00:00

[ Upstream commit 82a40777de12728dedf4075453b694f0d1baee80 ]

According to RFC791, 68 bytes is the minimum size of IPv4 datagram every
device must be able to forward without further fragmentation while 576
bytes is the minimum size of IPv4 datagram every device has to be able
to receive, so in ip6_tnl_xmit(), 68(IPV4_MIN_MTU) should be the right
value for the ipv4 min mtu check in ip6_tnl_xmit.

While at it, change to use max() instead of if statement.

Fixes: c9fefa08190f ("ip6_tunnel: get the min mtu properly in ip6_tnl_xmit")
Reported-by: Sabrina Dubroca 
Signed-off-by: Xin Long 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

multicast: do not restore deleted record source filter mode to new one

2018-07-28T05:49:11+00:00

There are two scenarios that we will restore deleted records. The first is
when device down and up(or unmap/remap). In this scenario the new filter
mode is same with previous one. Because we get it from in_dev->mc_list and
we do not touch it during device down and up.

The other scenario is when a new socket join a group which was just delete
and not finish sending status reports. In this scenario, we should use the
current filter mode instead of restore old one. Here are 4 cases in total.

old_socket        new_socket       before_fix       after_fix
  IN(A)             IN(A)           ALLOW(A)         ALLOW(A)
  IN(A)             EX( )           TO_IN( )         TO_EX( )
  EX( )             IN(A)           TO_EX( )         ALLOW(A)
  EX( )             EX( )           TO_EX( )         TO_EX( )

Fixes: 24803f38a5c0b (igmp: do not remove igmp souce list info when set link down)
Fixes: 1666d49e1d416 (mld: do not remove mld souce list info when set link down)
Signed-off-by: Hangbin Liu 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip: in cmsg IP(V6)_ORIGDSTADDR call pskb_may_pull

2018-07-28T05:49:11+00:00

[ Upstream commit 2efd4fca703a6707cad16ab486eaab8fc7f0fd49 ]

Syzbot reported a read beyond the end of the skb head when returning
IPV6_ORIGDSTADDR:

  BUG: KMSAN: kernel-infoleak in put_cmsg+0x5ef/0x860 net/core/scm.c:242
  CPU: 0 PID: 4501 Comm: syz-executor128 Not tainted 4.17.0+ #9
  Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
  Google 01/01/2011
  Call Trace:
    __dump_stack lib/dump_stack.c:77 [inline]
    dump_stack+0x185/0x1d0 lib/dump_stack.c:113
    kmsan_report+0x188/0x2a0 mm/kmsan/kmsan.c:1125
    kmsan_internal_check_memory+0x138/0x1f0 mm/kmsan/kmsan.c:1219
    kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1261
    copy_to_user include/linux/uaccess.h:184 [inline]
    put_cmsg+0x5ef/0x860 net/core/scm.c:242
    ip6_datagram_recv_specific_ctl+0x1cf3/0x1eb0 net/ipv6/datagram.c:719
    ip6_datagram_recv_ctl+0x41c/0x450 net/ipv6/datagram.c:733
    rawv6_recvmsg+0x10fb/0x1460 net/ipv6/raw.c:521
    [..]

This logic and its ipv4 counterpart read the destination port from
the packet at skb_transport_offset(skb) + 4.

With MSG_MORE and a local SOCK_RAW sender, syzbot was able to cook a
packet that stores headers exactly up to skb_transport_offset(skb) in
the head and the remainder in a frag.

Call pskb_may_pull before accessing the pointer to ensure that it lies
in skb head.

Link: http://lkml.kernel.org/r/CAF=yD-LEJwZj5a1-bAAj2Oy_hKmGygV6rsJ_WOrAYnv-fnayiQ@mail.gmail.com
Reported-by: syzbot+9adb4b567003cac781f0@syzkaller.appspotmail.com
Signed-off-by: Willem de Bruijn 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

ip: hash fragments consistently

2018-07-28T05:49:11+00:00

[ Upstream commit 3dd1c9a1270736029ffca670e9bd0265f4120600 ]

The skb hash for locally generated ip[v6] fragments belonging
to the same datagram can vary in several circumstances:
* for connected UDP[v6] sockets, the first fragment get its hash
  via set_owner_w()/skb_set_hash_from_sk()
* for unconnected IPv6 UDPv6 sockets, the first fragment can get
  its hash via ip6_make_flowlabel()/skb_get_hash_flowi6(), if
  auto_flowlabel is enabled

For the following frags the hash is usually computed via
skb_get_hash().
The above can cause OoO for unconnected IPv6 UDPv6 socket: in that
scenario the egress tx queue can be selected on a per packet basis
via the skb hash.
It may also fool flow-oriented schedulers to place fragments belonging
to the same datagram in different flows.

Fix the issue by copying the skb hash from the head frag into
the others at fragmentation time.

Before this commit:
perf probe -a "dev_queue_xmit skb skb->hash skb->l4_hash:b1@0/8 skb->sw_hash:b1@1/8"
netperf -H $IPV4 -t UDP_STREAM -l 5 -- -m 2000 -n &
perf record -e probe:dev_queue_xmit -e probe:skb_set_owner_w -a sleep 0.1
perf script
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=3713014309 l4_hash=1 sw_hash=0
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=0 l4_hash=0 sw_hash=0

After this commit:
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0
probe:dev_queue_xmit: (ffffffff8c6b1b20) hash=2171763177 l4_hash=1 sw_hash=0

Fixes: b73c3d0e4f0e ("net: Save TX flow hash in sock and set in skbuf on xmit")
Fixes: 67800f9b1f4e ("ipv6: Call skb_get_hash_flowi6 to get skb->hash in ip6_make_flowlabel")
Signed-off-by: Paolo Abeni 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman