Commit Graph

7354 Commits

Author SHA1 Message Date
Kangmin Park
46c7655f0b ipv6: decrease hop limit counter in ip6_forward()
Decrease hop limit counter when deliver skb to ndp proxy.

Signed-off-by: Kangmin Park <l4stpr0gr4m@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-23 16:40:41 +01:00
Vadim Fedorenko
9bfce73c89 udp: check encap socket in __udp_lib_err
Commit d26796ae58 ("udp: check udp sock encap_type in __udp_lib_err")
added checks for encapsulated sockets but it broke cases when there is
no implementation of encap_err_lookup for encapsulation, i.e. ESP in
UDP encapsulation. Fix it by calling encap_err_lookup only if socket
implements this method otherwise treat it as legal socket.

Fixes: d26796ae58 ("udp: check udp sock encap_type in __udp_lib_err")
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Reviewed-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-21 08:49:31 -07:00
Paolo Abeni
8fb4792f09 ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions
While running the self-tests on a KASAN enabled kernel, I observed a
slab-out-of-bounds splat very similar to the one reported in
commit 821bbf79fe ("ipv6: Fix KASAN: slab-out-of-bounds Read in
 fib6_nh_flush_exceptions").

We additionally need to take care of fib6_metrics initialization
failure when the caller provides an nh.

The fix is similar, explicitly free the route instead of calling
fib6_info_release on a half-initialized object.

Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-20 07:25:25 -07:00
Vasily Averin
2d85a1b31d ipv6: ip6_finish_output2: set sk into newly allocated nskb
skb_set_owner_w() should set sk not to old skb but to new nskb.

Fixes: 5796015fa9 ("ipv6: allocate enough headroom in ip6_finish_output2()")
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Link: https://lore.kernel.org/r/70c0744f-89ae-1869-7e3e-4fa292158f4b@virtuozzo.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-07-20 11:52:36 +02:00
Vasily Averin
5796015fa9 ipv6: allocate enough headroom in ip6_finish_output2()
When TEE target mirrors traffic to another interface, sk_buff may
not have enough headroom to be processed correctly.
ip_finish_output2() detect this situation for ipv4 and allocates
new skb with enogh headroom. However ipv6 lacks this logic in
ip_finish_output2 and it leads to skb_under_panic:

 skbuff: skb_under_panic: text:ffffffffc0866ad4 len:96 put:24
 head:ffff97be85e31800 data:ffff97be85e317f8 tail:0x58 end:0xc0 dev:gre0
 ------------[ cut here ]------------
 kernel BUG at net/core/skbuff.c:110!
 invalid opcode: 0000 [#1] SMP PTI
 CPU: 2 PID: 393 Comm: kworker/2:2 Tainted: G           OE     5.13.0 #13
 Hardware name: Virtuozzo KVM, BIOS 1.11.0-2.vz7.4 04/01/2014
 Workqueue: ipv6_addrconf addrconf_dad_work
 RIP: 0010:skb_panic+0x48/0x4a
 Call Trace:
  skb_push.cold.111+0x10/0x10
  ipgre_header+0x24/0xf0 [ip_gre]
  neigh_connected_output+0xae/0xf0
  ip6_finish_output2+0x1a8/0x5a0
  ip6_output+0x5c/0x110
  nf_dup_ipv6+0x158/0x1000 [nf_dup_ipv6]
  tee_tg6+0x2e/0x40 [xt_TEE]
  ip6t_do_table+0x294/0x470 [ip6_tables]
  nf_hook_slow+0x44/0xc0
  nf_hook.constprop.34+0x72/0xe0
  ndisc_send_skb+0x20d/0x2e0
  ndisc_send_ns+0xd1/0x210
  addrconf_dad_work+0x3c8/0x540
  process_one_work+0x1d1/0x370
  worker_thread+0x30/0x390
  kthread+0x116/0x130
  ret_from_fork+0x22/0x30

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-12 11:25:12 -07:00
Alexander Ovechkin
43b90bfad3 net: send SYNACK packet with accepted fwmark
commit e05a90ec9e ("net: reflect mark on tcp syn ack packets")
fixed IPv4 only.

This part is for the IPv6 side.

Fixes: e05a90ec9e ("net: reflect mark on tcp syn ack packets")
Signed-off-by: Alexander Ovechkin <ovov@yandex-team.ru>
Acked-by: Dmitry Yakunin <zeil@yandex-team.ru>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-09 11:24:02 -07:00
Eric Dumazet
c7bb4b8903 ipv6: tcp: drop silly ICMPv6 packet too big messages
While TCP stack scales reasonably well, there is still one part that
can be used to DDOS it.

IPv6 Packet too big messages have to lookup/insert a new route,
and if abused by attackers, can easily put hosts under high stress,
with many cpus contending on a spinlock while one is stuck in fib6_run_gc()

ip6_protocol_deliver_rcu()
 icmpv6_rcv()
  icmpv6_notify()
   tcp_v6_err()
    tcp_v6_mtu_reduced()
     inet6_csk_update_pmtu()
      ip6_rt_update_pmtu()
       __ip6_rt_update_pmtu()
        ip6_rt_cache_alloc()
         ip6_dst_alloc()
          dst_alloc()
           ip6_dst_gc()
            fib6_run_gc()
             spin_lock_bh() ...

Some of our servers have been hit by malicious ICMPv6 packets
trying to _increase_ the MTU/MSS of TCP flows.

We believe these ICMPv6 packets are a result of a bug in one ISP stack,
since they were blindly sent back for _every_ (small) packet sent to them.

These packets are for one TCP flow:
09:24:36.266491 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.266509 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.316688 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.316704 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240
09:24:36.608151 IP6 Addr1 > Victim ICMP6, packet too big, mtu 1460, length 1240

TCP stack can filter some silly requests :

1) MTU below IPV6_MIN_MTU can be filtered early in tcp_v6_err()
2) tcp_v6_mtu_reduced() can drop requests trying to increase current MSS.

This tests happen before the IPv6 routing stack is entered, thus
removing the potential contention and route exhaustion.

Note that IPv6 stack was performing these checks, but too late
(ie : after the route has been added, and after the potential
garbage collect war)

v2: fix typo caught by Martin, thanks !
v3: exports tcp_mtu_to_mss(), caught by David, thanks !

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-08 12:27:08 -07:00
Nicolas Dichtel
ccd27f05ae ipv6: fix 'disable_policy' for fwd packets
The goal of commit df789fe752 ("ipv6: Provide ipv6 version of
"disable_policy" sysctl") was to have the disable_policy from ipv4
available on ipv6.
However, it's not exactly the same mechanism. On IPv4, all packets coming
from an interface, which has disable_policy set, bypass the policy check.
For ipv6, this is done only for local packets, ie for packets destinated to
an address configured on the incoming interface.

Let's align ipv6 with ipv4 so that the 'disable_policy' sysctl has the same
effect for both protocols.

My first approach was to create a new kind of route cache entries, to be
able to set DST_NOPOLICY without modifying routes. This would have added a
lot of code. Because the local delivery path is already handled, I choose
to focus on the forwarding path to minimize code churn.

Fixes: df789fe752 ("ipv6: Provide ipv6 version of "disable_policy" sysctl")
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-06 15:23:07 -07:00
Eric Dumazet
561022acb1 tcp: annotate data races around tp->mtu_info
While tp->mtu_info is read while socket is owned, the write
sides happen from err handlers (tcp_v[46]_mtu_reduced)
which only own the socket spinlock.

Fixes: 563d34d057 ("tcp: dont drop MTU reduction indications")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-02 13:31:48 -07:00
Vadim Fedorenko
40fc3054b4 net: ipv6: fix return value of ip6_skb_dst_mtu
Commit 628a5c5618 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE") introduced
ip6_skb_dst_mtu with return value of signed int which is inconsistent
with actually returned values. Also 2 users of this function actually
assign its value to unsigned int variable and only __xfrm6_output
assigns result of this function to signed variable but actually uses
as unsigned in further comparisons and calls. Change this function
to return unsigned int value.

Fixes: 628a5c5618 ("[INET]: Add IP(V6)_PMTUDISC_RPOBE")
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-02 11:57:01 -07:00
Eric Dumazet
18a419bad6 udp: annotate data races around unix_sk(sk)->gso_size
Accesses to unix_sk(sk)->gso_size are lockless.
Add READ_ONCE()/WRITE_ONCE() around them.

BUG: KCSAN: data-race in udp_lib_setsockopt / udpv6_sendmsg

write to 0xffff88812d78f47c of 2 bytes by task 10849 on cpu 1:
 udp_lib_setsockopt+0x3b3/0x710 net/ipv4/udp.c:2696
 udpv6_setsockopt+0x63/0x90 net/ipv6/udp.c:1630
 sock_common_setsockopt+0x5d/0x70 net/core/sock.c:3265
 __sys_setsockopt+0x18f/0x200 net/socket.c:2104
 __do_sys_setsockopt net/socket.c:2115 [inline]
 __se_sys_setsockopt net/socket.c:2112 [inline]
 __x64_sys_setsockopt+0x62/0x70 net/socket.c:2112
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff88812d78f47c of 2 bytes by task 10852 on cpu 0:
 udpv6_sendmsg+0x161/0x16b0 net/ipv6/udp.c:1299
 inet6_sendmsg+0x5f/0x80 net/ipv6/af_inet6.c:642
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x360/0x4d0 net/socket.c:2337
 ___sys_sendmsg net/socket.c:2391 [inline]
 __sys_sendmmsg+0x315/0x4b0 net/socket.c:2477
 __do_sys_sendmmsg net/socket.c:2506 [inline]
 __se_sys_sendmmsg net/socket.c:2503 [inline]
 __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2503
 do_syscall_64+0x4a/0x90 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x0000 -> 0x0005

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 10852 Comm: syz-executor.0 Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: bec1f6f697 ("udp: generate gso with UDP_SEGMENT")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-01 13:23:19 -07:00
Jakub Kicinski
b6df00789e Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Trivial conflict in net/netfilter/nf_tables_api.c.

Duplicate fix in tools/testing/selftests/net/devlink_port_split.py
- take the net-next version.

skmsg, and L4 bpf - keep the bpf code but remove the flags
and err params.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-29 15:45:27 -07:00
Alexander Aring
e3ae2365ef net: sock: introduce sk_error_report
This patch introduces a function wrapper to call the sk_error_report
callback. That will prepare to add additional handling whenever
sk_error_report is called, for example to trace socket errors.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29 11:28:21 -07:00
Andreas Roeseler
1fd07f33c3 ipv6: ICMPV6: add response to ICMPV6 RFC 8335 PROBE messages
This patch builds off of commit 2b246b2569
and adds functionality to respond to ICMPV6 PROBE requests.

Add icmp_build_probe function to construct PROBE requests for both
ICMPV4 and ICMPV6.

Modify icmpv6_rcv to detect ICMPV6 PROBE messages and call the
icmpv6_echo_reply handler.

Modify icmpv6_echo_reply to build a PROBE response message based on the
queried interface.

This patch has been tested using a branch of the iputils git repo which can
be found here: https://github.com/Juniper-Clinic-2020/iputils/tree/probe-request

Signed-off-by: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 14:29:45 -07:00
David S. Miller
1b077ce1c5 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git
/klassert/ipsec-next

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2021-06-28

1) Remove an unneeded error assignment in esp4_gro_receive().
   From Yang Li.

2) Add a new byseq state hashtable to find acquire states faster.
   From Sabrina Dubroca.

3) Remove some unnecessary variables in pfkey_create().
   From zuoqilin.

4) Remove the unused description from xfrm_type struct.
   From Florian Westphal.

5) Fix a spelling mistake in the comment of xfrm_state_ok().
   From gushengxian.

6) Replace hdr_off indirections by a small helper function.
   From Florian Westphal.

7) Remove xfrm4_output_finish and xfrm6_output_finish declarations,
   they are not used anymore.From Antony Antony.

8) Remove xfrm replay indirections.
   From Florian Westphal.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 13:17:16 -07:00
Guillaume Nault
da5a2e49f0 ip6_tunnel: allow redirecting ip6gre and ipxip6 packets to eth devices
Reset the mac_header pointer even when the tunnel transports only L3
data (in the ARPHRD_ETHER case, this is already done by eth_type_trans).
This prevents other parts of the stack from mistakenly accessing the
outer header after the packet has been decapsulated.

In practice, this allows to push an Ethernet header to ipip6, ip6ip6,
mplsip6 or ip6gre packets and redirect them to an Ethernet device:

  $ tc filter add dev ip6tnl0 ingress matchall       \
      action vlan push_eth dst_mac 00:00:5e:00:53:01 \
                           src_mac 00:00:5e:00:53:00 \
      action mirred egress redirect dev eth0

Without this patch, push_eth refuses to add an ethernet header because
the skb appears to already have a MAC header.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 12:44:17 -07:00
Guillaume Nault
730eed2772 sit: allow redirecting ip6ip, ipip and mplsip packets to eth devices
Even though sit transports L3 data (IPv6, IPv4 or MPLS) packets, it
needs to reset the mac_header pointer, so that other parts of the stack
don't mistakenly access the outer header after the packet has been
decapsulated. There are two rx handlers to modify: ipip6_rcv() for the
ip6ip mode and sit_tunnel_rcv() which is used to re-implement the ipip
and mplsip modes of ipip.ko.

This allows to push an Ethernet header to sit packets and redirect
them to an Ethernet device:

  $ tc filter add dev sit0 ingress matchall          \
      action vlan push_eth dst_mac 00:00:5e:00:53:01 \
                           src_mac 00:00:5e:00:53:00 \
      action mirred egress redirect dev eth0

Without this patch, push_eth refuses to add an ethernet header because
the skb appears to already have a MAC header.

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-28 12:44:17 -07:00
zhang kai
c305b9e6d5 ipv6: delete useless dst check in ip6_dst_lookup_tail
parameter dst always points to null.

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 15:49:01 -07:00
Eric Dumazet
624085a31c ipv6: fix out-of-bound access in ip6_parse_tlv()
First problem is that optlen is fetched without checking
there is more than one byte to parse.

Fix this by taking care of IPV6_TLV_PAD1 before
fetching optlen (under appropriate sanity checks against len)

Second problem is that IPV6_TLV_PADN checks of zero
padding are performed before the check of remaining length.

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Fixes: c1412fce7e ("net/ipv6/exthdrs.c: Strict PadN option checking")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 12:42:57 -07:00
Jakub Kicinski
6d123b81ac net: ip: avoid OOM kills with large UDP sends over loopback
Dave observed number of machines hitting OOM on the UDP send
path. The workload seems to be sending large UDP packets over
loopback. Since loopback has MTU of 64k kernel will try to
allocate an skb with up to 64k of head space. This has a good
chance of failing under memory pressure. What's worse if
the message length is <32k the allocation may trigger an
OOM killer.

This is entirely avoidable, we can use an skb with page frags.

af_unix solves a similar problem by limiting the head
length to SKB_MAX_ALLOC. This seems like a good and simple
approach. It means that UDP messages > 16kB will now
use fragments if underlying device supports SG, if extra
allocator pressure causes regressions in real workloads
we can switch to trying the large allocation first and
falling back.

v4: pre-calculate all the additions to alloclen so
    we can be sure it won't go over order-2

Reported-by: Dave Jones <dsj@fb.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-24 11:17:21 -07:00
Eric Dumazet
bcc3f2a829 ipv6: exthdrs: do not blindly use init_net
I see no reason why max_dst_opts_cnt and max_hbh_opts_cnt
are fetched from the initial net namespace.

The other sysctls (max_dst_opts_len & max_hbh_opts_len)
are in fact already using the current ns.

Note: it is not clear why ipv6_destopt_rcv() use two ways to
get to the netns :

 1) dev_net(dst->dev)
    Originally used to increment IPSTATS_MIB_INHDRERRORS

 2) dev_net(skb->dev)
     Tom used this variant in his patch.

Maybe this calls to use ipv6_skb_net() instead ?

Fixes: 47d3d7ac65 ("ipv6: Implement limits on Hop-by-Hop and Destination options")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@quantonium.net>
Cc: Coco Li <lixiaoyan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 13:53:38 -07:00
David S. Miller
7c2becf796 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2021-06-23

1) Don't return a mtu smaller than 1280 on IPv6 pmtu discovery.
   From Sabrina Dubroca

2) Fix seqcount rcu-read side in xfrm_policy_lookup_bytype
   for the PREEMPT_RT case. From Varad Gautam.

3) Remove a repeated declaration of xfrm_parse_spi.
   From Shaokun Zhang.

4) IPv4 beet mode can't handle fragments, but IPv6 does.
   commit 68dc022d04 ("xfrm: BEET mode doesn't support
   fragments for inner packets") handled IPv4 and IPv6
   the same way. Relax the check for IPv6 because fragments
   are possible here. From Xin Long.

5) Memory allocation failures are not reported for
   XFRMA_ENCAP and XFRMA_COADDR in xfrm_state_construct.
   Fix this by moving both cases in front of the function.

6) Fix a missing initialization in the xfrm offload fallback
   fail case for bonding devices. From Ayush Sawal.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-23 12:34:15 -07:00
Jakub Kicinski
a6e3f2985a ip6_tunnel: fix GRE6 segmentation
Commit 6c11fbf97e ("ip6_tunnel: add MPLS transmit support")
moved assiging inner_ipproto down from ipxip6_tnl_xmit() to
its callee ip6_tnl_xmit(). The latter is also used by GRE.

Since commit 3872035241 ("gre: Use inner_proto to obtain inner
header protocol") GRE had been depending on skb->inner_protocol
during segmentation. It sets it in gre_build_header() and reads
it in gre_gso_segment(). Changes to ip6_tnl_xmit() overwrite
the protocol, resulting in GSO skbs getting dropped.

Note that inner_protocol is a union with inner_ipproto,
GRE uses the former while the change switched it to the latter
(always setting it to just IPPROTO_GRE).

Restore the original location of skb_set_inner_ipproto(),
it is unclear why it was moved in the first place.

Fixes: 6c11fbf97e ("ip6_tunnel: add MPLS transmit support")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-22 10:30:05 -07:00
Jakub Kicinski
adc2e56ebe Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Trivial conflicts in net/can/isotp.c and
tools/testing/selftests/net/mptcp/mptcp_connect.sh

scaled_ppm_to_ppb() was moved from drivers/ptp/ptp_clock.c
to include/linux/ptp_clock_kernel.h in -next so re-apply
the fix there.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-18 19:47:02 -07:00
Andrea Mayer
8b532109bf seg6: add support for SRv6 End.DT46 Behavior
IETF RFC 8986 [1] includes the definition of SRv6 End.DT4, End.DT6, and
End.DT46 Behaviors.

The current SRv6 code in the Linux kernel only implements End.DT4 and
End.DT6 which can be used respectively to support IPv4-in-IPv6 and
IPv6-in-IPv6 VPNs. With End.DT4 and End.DT6 it is not possible to create a
single SRv6 VPN tunnel to carry both IPv4 and IPv6 traffic.

The proposed End.DT46 implementation is meant to support the decapsulation
of IPv4 and IPv6 traffic coming from a single SRv6 tunnel.
The implementation of the SRv6 End.DT46 Behavior in the Linux kernel
greatly simplifies the setup and operations of SRv6 VPNs.

The SRv6 End.DT46 Behavior leverages the infrastructure of SRv6 End.DT{4,6}
Behaviors implemented so far, because it makes use of a VRF device in
order to force the routing lookup into the associated routing table.

To make the End.DT46 work properly, it must be guaranteed that the routing
table used for routing lookup operations is bound to one and only one VRF
during the tunnel creation. Such constraint has to be enforced by enabling
the VRF strict_mode sysctl parameter, i.e.:

 $ sysctl -wq net.vrf.strict_mode=1

Note that the same approach is used for the SRv6 End.DT4 Behavior and for
the End.DT6 Behavior in VRF mode.

The command used to instantiate an SRv6 End.DT46 Behavior is
straightforward, i.e.:

 $ ip -6 route add 2001:db8::1 encap seg6local action End.DT46 vrftable 100 dev vrf100.

[1] https://www.rfc-editor.org/rfc/rfc8986.html#name-enddt46-decapsulation-and-s

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Performance and impact of SRv6 End.DT46 Behavior on the SRv6 Networking
=======================================================================

This patch aims to add the SRv6 End.DT46 Behavior with minimal impact on
the performance of SRv6 End.DT4 and End.DT6 Behaviors.
In order to verify this, we tested the performance of the newly introduced
SRv6 End.DT46 Behavior and compared it with the performance of SRv6
End.DT{4,6} Behaviors, considering both the patched kernel and the kernel
before applying the End.DT46 patch (referred to as vanilla kernel).

In details, the following decapsulation scenarios were considered:

 1.a) IPv6 traffic in SRv6 End.DT46 Behavior on patched kernel;
 1.b) IPv4 traffic in SRv6 End.DT46 Behavior on patched kernel;
 2.a) SRv6 End.DT6 Behavior (VRF mode) on patched kernel;
 2.b) SRv6 End.DT4 Behavior on patched kernel;
 3.a) SRv6 End.DT6 Behavior (VRF mode) on vanilla kernel (without the
      End.DT46 patch);
 3.b) SRv6 End.DT4 Behavior on vanilla kernel (without the End.DT46 patch).

All tests were performed on a testbed deployed on the CloudLab [2]
facilities. We considered IPv{4,6} traffic handled by a single core (at 2.4
GHz on a Xeon(R) CPU E5-2630 v3) on kernel 5.13-rc1 using packets of size
~ 100 bytes.

Scenario (1.a): average 684.70 kpps; std. dev. 0.7 kpps;
Scenario (1.b): average 711.69 kpps; std. dev. 1.2 kpps;
Scenario (2.a): average 690.70 kpps; std. dev. 1.2 kpps;
Scenario (2.b): average 722.22 kpps; std. dev. 1.7 kpps;
Scenario (3.a): average 690.02 kpps; std. dev. 2.6 kpps;
Scenario (3.b): average 721.91 kpps; std. dev. 1.2 kpps;

Considering the results for the patched kernel (1.a, 1.b, 2.a, 2.b) we
observe that the performance degradation incurred in using End.DT46 rather
than End.DT6 and End.DT4 respectively for IPv6 and IPv4 traffic is minimal,
around 0.9% and 1.5%. Such very minimal performance degradation is the
price to be paid if one prefers to use a single tunnel capable of handling
both types of traffic (IPv4 and IPv6).

Comparing the results for End.DT4 and End.DT6 under the patched and the
vanilla kernel (2.a, 2.b, 3.a, 3.b) we observe that the introduction of the
End.DT46 patch has no impact on the performance of End.DT4 and End.DT6.

[2] https://www.cloudlab.us

Signed-off-by: Andrea Mayer <andrea.mayer@uniroma2.it>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-18 11:35:47 -07:00
David S. Miller
a52171ae7b Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2021-06-17

The following pull-request contains BPF updates for your *net-next* tree.

We've added 50 non-merge commits during the last 25 day(s) which contain
a total of 148 files changed, 4779 insertions(+), 1248 deletions(-).

The main changes are:

1) BPF infrastructure to migrate TCP child sockets from a listener to another
   in the same reuseport group/map, from Kuniyuki Iwashima.

2) Add a provably sound, faster and more precise algorithm for tnum_mul() as
   noted in https://arxiv.org/abs/2105.05398, from Harishankar Vishwanathan.

3) Streamline error reporting changes in libbpf as planned out in the
   'libbpf: the road to v1.0' effort, from Andrii Nakryiko.

4) Add broadcast support to xdp_redirect_map(), from Hangbin Liu.

5) Extends bpf_map_lookup_and_delete_elem() functionality to 4 more map
   types, that is, {LRU_,PERCPU_,LRU_PERCPU_,}HASH, from Denis Salopek.

6) Support new LLVM relocations in libbpf to make them more linker friendly,
   also add a doc to describe the BPF backend relocations, from Yonghong Song.

7) Silence long standing KUBSAN complaints on register-based shifts in
   interpreter, from Daniel Borkmann and Eric Biggers.

8) Add dummy PT_REGS macros in libbpf to fail BPF program compilation when
   target arch cannot be determined, from Lorenz Bauer.

9) Extend AF_XDP to support large umems with 1M+ pages, from Magnus Karlsson.

10) Fix two minor libbpf tc BPF API issues, from Kumar Kartikeya Dwivedi.

11) Move libbpf BPF_SEQ_PRINTF/BPF_SNPRINTF macros that can be used by BPF
    programs to bpf_helpers.h header, from Florent Revest.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-17 11:54:56 -07:00
Kuniyuki Iwashima
d4f2c86b2b tcp: Migrate TCP_NEW_SYN_RECV requests at receiving the final ACK.
This patch also changes the code to call reuseport_migrate_sock() and
inet_reqsk_clone(), but unlike the other cases, we do not call
inet_reqsk_clone() right after reuseport_migrate_sock().

Currently, in the receive path for TCP_NEW_SYN_RECV sockets, its listener
has three kinds of refcnt:

  (A) for listener itself
  (B) carried by reuqest_sock
  (C) sock_hold() in tcp_v[46]_rcv()

While processing the req, (A) may disappear by close(listener). Also, (B)
can disappear by accept(listener) once we put the req into the accept
queue. So, we have to hold another refcnt (C) for the listener to prevent
use-after-free.

For socket migration, we call reuseport_migrate_sock() to select a listener
with (A) and to increment the new listener's refcnt in tcp_v[46]_rcv().
This refcnt corresponds to (C) and is cleaned up later in tcp_v[46]_rcv().
Thus we have to take another refcnt (B) for the newly cloned request_sock.

In inet_csk_complete_hashdance(), we hold the count (B), clone the req, and
try to put the new req into the accept queue. By migrating req after
winning the "own_req" race, we can avoid such a worst situation:

  CPU 1 looks up req1
  CPU 2 looks up req1, unhashes it, then CPU 1 loses the race
  CPU 3 looks up req2, unhashes it, then CPU 2 loses the race
  ...

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210612123224.12525-8-kuniyu@amazon.co.jp
2021-06-15 18:01:06 +02:00
Taehee Yoo
ffa85b73c3 mld: avoid unnecessary high order page allocation in mld_newpack()
If link mtu is too big, mld_newpack() allocates high-order page.
But most mld packets don't need high-order page.
So, it might waste unnecessary pages.
To avoid this, it makes mld_newpack() try to allocate order-0 page.

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-14 12:46:00 -07:00
Colin Ian King
b5ec0705ff ipv6: fib6: remove redundant initialization of variable err
The variable err is being initialized with a value that is never read, the
assignment is redundant and can be removed.

Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-14 12:42:26 -07:00
Florian Westphal
d1002d2490 xfrm: remove hdr_offset indirection
After previous patches all remaining users set the function pointer to
the same function: xfrm6_find_1stfragopt.

So remove this function pointer and call ip6_find_1stfragopt directly.

Reduces size of xfrm_type to 64 bytes on 64bit platforms.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2021-06-11 14:48:50 +02:00
Florian Westphal
848b18fb7f xfrm: ipv6: move mip6_rthdr_offset into xfrm core
Place the call into the xfrm core.  After this all remaining users
set the hdr_offset function pointer to the same function which opens
the possiblity to remove the indirection.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2021-06-11 14:48:50 +02:00
Florian Westphal
37b9e7eb55 xfrm: ipv6: move mip6_destopt_offset into xfrm core
This helper is relatively small, just move this to the xfrm core
and call it directly.

Next patch does the same for the ROUTING type.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2021-06-11 14:48:50 +02:00
David S. Miller
22488e4550 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Fix a crash when stateful expression with its own gc callback
   is used in a set definition.

2) Skip IPv6 packets from any link-local address in IPv6 fib expression.
   Add a selftest for this scenario, from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-10 14:33:56 -07:00
Paolo Abeni
a8b897c7bc udp: fix race between close() and udp_abort()
Kaustubh reported and diagnosed a panic in udp_lib_lookup().
The root cause is udp_abort() racing with close(). Both
racing functions acquire the socket lock, but udp{v6}_destroy_sock()
release it before performing destructive actions.

We can't easily extend the socket lock scope to avoid the race,
instead use the SOCK_DEAD flag to prevent udp_abort from doing
any action when the critical race happens.

Diagnosed-and-tested-by: Kaustubh Pandey <kapandey@codeaurora.org>
Fixes: 5d77dca828 ("net: diag: support SOCK_DESTROY for UDP sockets")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-09 14:08:41 -07:00
Florian Westphal
12f36e9bf6 netfilter: nft_fib_ipv6: skip ipv6 packets from any to link-local
The ip6tables rpfilter match has an extra check to skip packets with
"::" source address.

Extend this to ipv6 fib expression.  Else ipv6 duplicate address detection
packets will fail rpf route check -- lookup returns -ENETUNREACH.

While at it, extend the prerouting check to also cover the ingress hook.

Closes: https://bugzilla.netfilter.org/show_bug.cgi?id=1543
Fixes: f6d0cbcf09 ("netfilter: nf_tables: add fib expression")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-06-09 21:11:03 +02:00
Florian Westphal
152bca0902 xfrm: remove description from xfrm_type struct
Its set but never read. Reduces size of xfrm_type to 64 bytes on 64bit.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2021-06-09 09:38:52 +02:00
Zheng Yongjun
5ac6b198d7 net: ipv4: Remove unneed BUG() function
When 'nla_parse_nested_deprecated' failed, it's no need to
BUG() here, return -EINVAL is ok.

Signed-off-by: Zheng Yongjun <zhengyongjun3@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-08 11:36:48 -07:00
David S. Miller
126285651b Merge ra.kernel.org:/pub/scm/linux/kernel/git/netdev/net
Bug fixes overlapping feature additions and refactoring, mostly.

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-07 13:01:52 -07:00
Coco Li
821bbf79fe ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions
Reported by syzbot:
HEAD commit:    90c911ad Merge tag 'fixes' of git://git.kernel.org/pub/scm..
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
dashboard link: https://syzkaller.appspot.com/bug?extid=123aa35098fd3c000eb7
compiler:       Debian clang version 11.0.1-2

==================================================================
BUG: KASAN: slab-out-of-bounds in fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline]
BUG: KASAN: slab-out-of-bounds in fib6_nh_flush_exceptions+0xbd/0x360 net/ipv6/route.c:1732
Read of size 8 at addr ffff8880145c78f8 by task syz-executor.4/17760

CPU: 0 PID: 17760 Comm: syz-executor.4 Not tainted 5.12.0-rc8-syzkaller #0
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x202/0x31e lib/dump_stack.c:120
 print_address_description+0x5f/0x3b0 mm/kasan/report.c:232
 __kasan_report mm/kasan/report.c:399 [inline]
 kasan_report+0x15c/0x200 mm/kasan/report.c:416
 fib6_nh_get_excptn_bucket net/ipv6/route.c:1604 [inline]
 fib6_nh_flush_exceptions+0xbd/0x360 net/ipv6/route.c:1732
 fib6_nh_release+0x9a/0x430 net/ipv6/route.c:3536
 fib6_info_destroy_rcu+0xcb/0x1c0 net/ipv6/ip6_fib.c:174
 rcu_do_batch kernel/rcu/tree.c:2559 [inline]
 rcu_core+0x8f6/0x1450 kernel/rcu/tree.c:2794
 __do_softirq+0x372/0x7a6 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu+0x22c/0x260 kernel/softirq.c:422
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:434
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:lock_acquire+0x1f6/0x720 kernel/locking/lockdep.c:5515
Code: f6 84 24 a1 00 00 00 02 0f 85 8d 02 00 00 f7 c3 00 02 00 00 49 bd 00 00 00 00 00 fc ff df 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 3d 00 00 00 00 00 4b c7 44 3d 09 00 00 00 00 43 c7 44 3d
RSP: 0018:ffffc90009e06560 EFLAGS: 00000206
RAX: 1ffff920013c0cc0 RBX: 0000000000000246 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90009e066e0 R08: dffffc0000000000 R09: fffffbfff1f992b1
R10: fffffbfff1f992b1 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff920013c0cb4
 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:267
 rcu_read_lock include/linux/rcupdate.h:656 [inline]
 ext4_get_group_info+0xea/0x340 fs/ext4/ext4.h:3231
 ext4_mb_prefetch+0x123/0x5d0 fs/ext4/mballoc.c:2212
 ext4_mb_regular_allocator+0x8a5/0x28f0 fs/ext4/mballoc.c:2379
 ext4_mb_new_blocks+0xc6e/0x24f0 fs/ext4/mballoc.c:4982
 ext4_ext_map_blocks+0x2be3/0x7210 fs/ext4/extents.c:4238
 ext4_map_blocks+0xab3/0x1cb0 fs/ext4/inode.c:638
 ext4_getblk+0x187/0x6c0 fs/ext4/inode.c:848
 ext4_bread+0x2a/0x1c0 fs/ext4/inode.c:900
 ext4_append+0x1a4/0x360 fs/ext4/namei.c:67
 ext4_init_new_dir+0x337/0xa10 fs/ext4/namei.c:2768
 ext4_mkdir+0x4b8/0xc00 fs/ext4/namei.c:2814
 vfs_mkdir+0x45b/0x640 fs/namei.c:3819
 ovl_do_mkdir fs/overlayfs/overlayfs.h:161 [inline]
 ovl_mkdir_real+0x53/0x1a0 fs/overlayfs/dir.c:146
 ovl_create_real+0x280/0x490 fs/overlayfs/dir.c:193
 ovl_workdir_create+0x425/0x600 fs/overlayfs/super.c:788
 ovl_make_workdir+0xed/0x1140 fs/overlayfs/super.c:1355
 ovl_get_workdir fs/overlayfs/super.c:1492 [inline]
 ovl_fill_super+0x39ee/0x5370 fs/overlayfs/super.c:2035
 mount_nodev+0x52/0xe0 fs/super.c:1413
 legacy_get_tree+0xea/0x180 fs/fs_context.c:592
 vfs_get_tree+0x86/0x270 fs/super.c:1497
 do_new_mount fs/namespace.c:2903 [inline]
 path_mount+0x196f/0x2be0 fs/namespace.c:3233
 do_mount fs/namespace.c:3246 [inline]
 __do_sys_mount fs/namespace.c:3454 [inline]
 __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3431
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x4665f9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f68f2b87188 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9
RDX: 00000000200000c0 RSI: 0000000020000000 RDI: 000000000040000a
RBP: 00000000004bfbb9 R08: 0000000020000100 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60
R13: 00007ffe19002dff R14: 00007f68f2b87300 R15: 0000000000022000

Allocated by task 17768:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:427 [inline]
 ____kasan_kmalloc+0xc2/0xf0 mm/kasan/common.c:506
 kasan_kmalloc include/linux/kasan.h:233 [inline]
 __kmalloc+0xb4/0x380 mm/slub.c:4055
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:684 [inline]
 fib6_info_alloc+0x2c/0xd0 net/ipv6/ip6_fib.c:154
 ip6_route_info_create+0x55d/0x1a10 net/ipv6/route.c:3638
 ip6_route_add+0x22/0x120 net/ipv6/route.c:3728
 inet6_rtm_newroute+0x2cd/0x2260 net/ipv6/route.c:5352
 rtnetlink_rcv_msg+0xb34/0xe70 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x1f0/0x460 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x7de/0x9b0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0xaa6/0xe90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x5a2/0x900 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmsg+0x319/0x400 net/socket.c:2433
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Last potentially related work creation:
 kasan_save_stack+0x27/0x50 mm/kasan/common.c:38
 kasan_record_aux_stack+0xee/0x120 mm/kasan/generic.c:345
 __call_rcu kernel/rcu/tree.c:3039 [inline]
 call_rcu+0x1b1/0xa30 kernel/rcu/tree.c:3114
 fib6_info_release include/net/ip6_fib.h:337 [inline]
 ip6_route_info_create+0x10c4/0x1a10 net/ipv6/route.c:3718
 ip6_route_add+0x22/0x120 net/ipv6/route.c:3728
 inet6_rtm_newroute+0x2cd/0x2260 net/ipv6/route.c:5352
 rtnetlink_rcv_msg+0xb34/0xe70 net/core/rtnetlink.c:5553
 netlink_rcv_skb+0x1f0/0x460 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1312 [inline]
 netlink_unicast+0x7de/0x9b0 net/netlink/af_netlink.c:1338
 netlink_sendmsg+0xaa6/0xe90 net/netlink/af_netlink.c:1927
 sock_sendmsg_nosec net/socket.c:654 [inline]
 sock_sendmsg net/socket.c:674 [inline]
 ____sys_sendmsg+0x5a2/0x900 net/socket.c:2350
 ___sys_sendmsg net/socket.c:2404 [inline]
 __sys_sendmsg+0x319/0x400 net/socket.c:2433
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Second to last potentially related work creation:
 kasan_save_stack+0x27/0x50 mm/kasan/common.c:38
 kasan_record_aux_stack+0xee/0x120 mm/kasan/generic.c:345
 insert_work+0x54/0x400 kernel/workqueue.c:1331
 __queue_work+0x981/0xcc0 kernel/workqueue.c:1497
 queue_work_on+0x111/0x200 kernel/workqueue.c:1524
 queue_work include/linux/workqueue.h:507 [inline]
 call_usermodehelper_exec+0x283/0x470 kernel/umh.c:433
 kobject_uevent_env+0x1349/0x1730 lib/kobject_uevent.c:617
 kvm_uevent_notify_change+0x309/0x3b0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4809
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:877 [inline]
 kvm_put_kvm+0x9c/0xd10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:920
 kvm_vcpu_release+0x53/0x60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3120
 __fput+0x352/0x7b0 fs/file_table.c:280
 task_work_run+0x146/0x1c0 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x10b/0x1e0 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x26/0x70 kernel/entry/common.c:301
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff8880145c7800
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 56 bytes to the right of
 192-byte region [ffff8880145c7800, ffff8880145c78c0)
The buggy address belongs to the page:
page:ffffea00005171c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x145c7
flags: 0xfff00000000200(slab)
raw: 00fff00000000200 ffffea00006474c0 0000000200000002 ffff888010c41a00
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880145c7780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880145c7800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880145c7880: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
                                                                ^
 ffff8880145c7900: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880145c7980: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================

In the ip6_route_info_create function, in the case that the nh pointer
is not NULL, the fib6_nh in fib6_info has not been allocated.
Therefore, when trying to free fib6_info in this error case using
fib6_info_release, the function will call fib6_info_destroy_rcu,
which it will access fib6_nh_release(f6i->fib6_nh);
However, f6i->fib6_nh doesn't have any refcount yet given the lack of allocation
causing the reported memory issue above.
Therefore, releasing the empty pointer directly instead would be the solution.

Fixes: f88d8ea67f ("ipv6: Plumb support for nexthop object in a fib6_info")
Fixes: 706ec91916 ("ipv6: Fix nexthop refcnt leak when creating ipv6 route info")
Signed-off-by: Coco Li <lixiaoyan@google.com>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 15:19:49 -07:00
zhang kai
261ba78cc3 sit: set name of device back to struct parms
addrconf_set_sit_dstaddr will use parms->name.

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-03 13:57:36 -07:00
zhang kai
7f0e869c4e sit: replace 68 with micro IPV4_MIN_MTU
Use meaningfull micro IPV4_MIN_MTU

Signed-off-by: zhang kai <zhangkaiheb@126.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-02 13:28:05 -07:00
David S. Miller
5fe8e519e4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Support for SCTP chunks matching on nf_tables, from Phil Sutter.

2) Skip LDMXCSR, we don't need a valid MXCSR state. From Stefano Brivio.

3) CONFIG_RETPOLINE for nf_tables set lookups, from Florian Westphal.

4) A few Kconfig leading spaces removal, from Juerg Haefliger.

5) Remove spinlock from xt_limit, from Jason Baron.

6) Remove useless initialization in xt_CT, oneliner from Yang Li.

7) Tree-wide replacement of netlink_unicast() by nfnetlink_unicast().

8) Reduce footprint of several structures: xt_action_param,
   nft_pktinfo and nf_hook_state, from Florian.

10) Add nft_thoff() and nft_sk() helpers and use them, also from Florian.

11) Fix documentation in nf_tables pipapo avx2, from Florian Westphal.

12) Fix clang-12 fmt string warnings, also from Florian.
====================
2021-06-01 17:15:14 -07:00
Rocco Yue
12e64b3bb9 ipv6: align code with context
The Tab key is used three times, causing the code block to
be out of alignment with the context.

Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Link: https://lore.kernel.org/r/20210530113811.8817-1-rocco.yue@mediatek.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-31 22:14:15 -07:00
Willy Tarreau
62f20e068c ipv6: use prandom_u32() for ID generation
This is a complement to commit aa6dd211e4 ("inet: use bigger hash
table for IP ID generation"), but focusing on some specific aspects
of IPv6.

Contary to IPv4, IPv6 only uses packet IDs with fragments, and with a
minimum MTU of 1280, it's much less easy to force a remote peer to
produce many fragments to explore its ID sequence. In addition packet
IDs are 32-bit in IPv6, which further complicates their analysis. On
the other hand, it is often easier to choose among plenty of possible
source addresses and partially work around the bigger hash table the
commit above permits, which leaves IPv6 partially exposed to some
possibilities of remote analysis at the risk of weakening some
protocols like DNS if some IDs can be predicted with a good enough
probability.

Given the wide range of permitted IDs, the risk of collision is extremely
low so there's no need to rely on the positive increment algorithm that
is shared with the IPv4 code via ip_idents_reserve(). We have a fast
PRNG, so let's simply call prandom_u32() and be done with it.

Performance measurements at 10 Gbps couldn't show any difference with
the previous code, even when using a single core, because due to the
large fragments, we're limited to only ~930 kpps at 10 Gbps and the cost
of the random generation is completely offset by other operations and by
the network transfer time. In addition, this change removes the need to
update a shared entry in the idents table so it may even end up being
slightly faster on large scale systems where this matters.

The risk of at least one collision here is about 1/80 million among
10 IDs, 1/850k among 100 IDs, and still only 1/8.5k among 1000 IDs,
which remains very low compared to IPv4 where all IDs are reused
every 4 to 80ms on a 10 Gbps flow depending on packet sizes.

Reported-by: Amit Klein <aksecurity@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20210529110746.6796-1-w@1wt.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-31 22:12:08 -07:00
Florian Westphal
85554eb981 netfilter: nf_tables: add and use nft_sk helper
This allows to change storage placement later on without changing readers.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-29 01:04:53 +02:00
Florian Westphal
586d5a8bce netfilter: x_tables: reduce xt_action_param by 8 byte
The fragment offset in ipv4/ipv6 is a 16bit field, so use
u16 instead of unsigned int.

On 64bit: 40 bytes to 32 bytes. By extension this also reduces
nft_pktinfo (56 to 48 byte).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-05-29 01:04:53 +02:00
Jakub Kicinski
5ada57a9a6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
cdc-wdm: s/kill_urbs/poison_urbs/ to fix build

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-05-27 09:55:10 -07:00
Francesco Ruggeri
e29f011e8f ipv6: record frag_max_size in atomic fragments in input path
Commit dbd1759e6a ("ipv6: on reassembly, record frag_max_size")
filled the frag_max_size field in IP6CB in the input path.
The field should also be filled in case of atomic fragments.

Fixes: dbd1759e6a ('ipv6: on reassembly, record frag_max_size')
Signed-off-by: Francesco Ruggeri <fruggeri@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-21 15:02:25 -07:00
Ido Schimmel
eb0e4d59b6 net: Add notifications when multipath hash field change
In-kernel notifications are already sent when the multipath hash policy
itself changes, but not when the multipath hash fields change.

Add these notifications, so that interested listeners (e.g., switch ASIC
drivers) could perform the necessary configuration.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-19 12:47:47 -07:00
Ido Schimmel
73c2c5cbb1 ipv6: Add custom multipath hash policy
Add a new multipath hash policy where the packet fields used for hash
calculation are determined by user space via the
fib_multipath_hash_fields sysctl that was introduced in the previous
patch.

The current set of available packet fields includes both outer and inner
fields, which requires two invocations of the flow dissector. Avoid
unnecessary dissection of the outer or inner flows by skipping
dissection if none of the outer or inner fields are required.

In accordance with the existing policies, when an skb is not available,
packet fields are extracted from the provided flow key. In which case,
only outer fields are considered.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18 13:27:32 -07:00