Commit Graph

47909 Commits

Author SHA1 Message Date
Mike Manning 6819a14ecb net: ipv6: fix regression of no RTM_DELADDR sent after DAD failure
Commit f784ad3d79 ("ipv6: do not send RTM_DELADDR for tentative
addresses") incorrectly assumes that no RTM_NEWADDR are sent for
addresses in tentative state, as this does happen for the standard
IPv6 use-case of DAD failure, see the call to ipv6_ifa_notify() in
addconf_dad_stop(). So as a result of this change, no RTM_DELADDR is
sent after DAD failure for a link-local when strict DAD (accept_dad=2)
is configured, or on the next admin down in other cases. The absence
of this notification breaks backwards compatibility and causes problems
after DAD failure if this notification was being relied on. The
solution is to allow RTM_DELADDR to still be sent after DAD failure.

Fixes: f784ad3d79 ("ipv6: do not send RTM_DELADDR for tentative addresses")
Signed-off-by: Mike Manning <mmanning@brocade.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19 16:42:09 -07:00
Daniel Borkmann 7c30013133 bpf: fix ri->map_owner pointer on bpf_prog_realloc
Commit 109980b894 ("bpf: don't select potentially stale
ri->map from buggy xdp progs") passed the pointer to the prog
itself to be loaded into r4 prior on bpf_redirect_map() helper
call, so that we can store the owner into ri->map_owner out of
the helper.

Issue with that is that the actual address of the prog is still
subject to change when subsequent rewrites occur that require
slow path in bpf_prog_realloc() to alloc more memory, e.g. from
patching inlining helper functions or constant blinding. Thus,
we really need to take prog->aux as the address we're holding,
which also works with prog clones as they share the same aux
object.

Instead of then fetching aux->prog during runtime, which could
potentially incur cache misses due to false sharing, we are
going to just use aux for comparison on the map owner. This
will also keep the patchlet of the same size, and later check
in xdp_map_invalid() only accesses read-only aux pointer from
the prog, it's also in the same cacheline already from prior
access when calling bpf_func.

Fixes: 109980b894 ("bpf: don't select potentially stale ri->map from buggy xdp progs")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19 16:38:53 -07:00
Eric Dumazet b5b7db8d68 tcp: fastopen: fix on syn-data transmit failure
Our recent change exposed a bug in TCP Fastopen Client that syzkaller
found right away [1]

When we prepare skb with SYN+DATA, we attempt to transmit it,
and we update socket state as if the transmit was a success.

In socket RTX queue we have two skbs, one with the SYN alone,
and a second one containing the DATA.

When (malicious) ACK comes in, we now complain that second one had no
skb_mstamp.

The proper fix is to make sure that if the transmit failed, we do not
pretend we sent the DATA skb, and make it our send_head.

When 3WHS completes, we can now send the DATA right away, without having
to wait for a timeout.

[1]
WARNING: CPU: 0 PID: 100189 at net/ipv4/tcp_input.c:3117 tcp_clean_rtx_queue+0x2057/0x2ab0 net/ipv4/tcp_input.c:3117()

 WARN_ON_ONCE(last_ackt == 0);

Modules linked in:
CPU: 0 PID: 100189 Comm: syz-executor1 Not tainted
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 0000000000000000 ffff8800b35cb1d8 ffffffff81cad00d 0000000000000000
 ffffffff828a4347 ffff88009f86c080 ffffffff8316eb20 0000000000000d7f
 ffff8800b35cb220 ffffffff812c33c2 ffff8800baad2440 00000009d46575c0
Call Trace:
 [<ffffffff81cad00d>] __dump_stack
 [<ffffffff81cad00d>] dump_stack+0xc1/0x124
 [<ffffffff812c33c2>] warn_slowpath_common+0xe2/0x150
 [<ffffffff812c361e>] warn_slowpath_null+0x2e/0x40
 [<ffffffff828a4347>] tcp_clean_rtx_queue+0x2057/0x2ab0 n
 [<ffffffff828ae6fd>] tcp_ack+0x151d/0x3930
 [<ffffffff828baa09>] tcp_rcv_state_process+0x1c69/0x4fd0
 [<ffffffff828efb7f>] tcp_v4_do_rcv+0x54f/0x7c0
 [<ffffffff8258aacb>] sk_backlog_rcv
 [<ffffffff8258aacb>] __release_sock+0x12b/0x3a0
 [<ffffffff8258ad9e>] release_sock+0x5e/0x1c0
 [<ffffffff8294a785>] inet_wait_for_connect
 [<ffffffff8294a785>] __inet_stream_connect+0x545/0xc50
 [<ffffffff82886f08>] tcp_sendmsg_fastopen
 [<ffffffff82886f08>] tcp_sendmsg+0x2298/0x35a0
 [<ffffffff82952515>] inet_sendmsg+0xe5/0x520
 [<ffffffff8257152f>] sock_sendmsg_nosec
 [<ffffffff8257152f>] sock_sendmsg+0xcf/0x110

Fixes: 8c72c65b42 ("tcp: update skb->skb_mstamp more carefully")
Fixes: 783237e8da ("net-tcp: Fast Open client - sending SYN-data")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19 16:16:51 -07:00
David S. Miller fd0e4c5999 Just two netlink fixes, both allowing privileged users
to crash the kernel with malformed netlink messages.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEExu3sM/nZ1eRSfR9Ha3t4Rpy0AB0FAlnAxN8ACgkQa3t4Rpy0
 AB30Xw/+I4GXH2gVfqgizM8nBwSsC5qP4QFqRQmvM+Z9k4hShptb1xZEUMWRCXr5
 vZJUjAb3X+YiqfuhCgNnoyb9ZEKCsQ7zOYLP1sO7LmTsTn/BX33XGdFSPC+XQNXl
 UEsCuWnX/BtmL6rxRbFxR4suJzWF7bnlyMeQLqso153OGUoZHcMlp9zTWlwLlVzg
 Q33iBhoNN6PY6ZiFKsYhq3w60EozLMKIQO7NHUj4DVYoQRzQxxJImJ6/44ZmXjvX
 Fsu7tBNlcC/9sS3qYcdFWMrN4T9vpAYJFhFTGvlkf0rB7aXXBizpNuiYoDUALcl/
 llTT4jVwglP1oKyXlJ3zUrTRnMuA4kw/d03Be+f5n2oloxZRGFPVDNLdIDkqEKBM
 kc3BSfBTo3jH8xR57d6KZVaiS8C+0uvvmJYd9y+fltMqMUFOMa48GB9gcGZa3myJ
 R5eeb7CVIiiXxKIH+Ma6LRksavzQg0qqt5vtY4TWy3pz6NdL2lEjsPqli2NgGgGU
 5DD14Qs2rUflqtAW+KA321pO02aciZi/MAHHHgQu5wDhH6+20pPSqX9ypIJK1AbI
 35oFwCauWnfANe3GwFmkvKnRGOs+z8gLBE5kRtp3YX9b+tRbhvnVSYDyf78tU7u3
 SYJk+mKBlvTthBB1vMy+7s2xUhcTjCdLXs7e1BNJdN2gr/gDIJY=
 =097A
 -----END PGP SIGNATURE-----

Merge tag 'mac80211-for-davem-2017-11-19' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211

Johannes Berg says:

====================
Just two netlink fixes, both allowing privileged users
to crash the kernel with malformed netlink messages.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-19 10:51:08 -07:00
Yuchung Cheng 4c7124413a tcp: remove two unused functions
remove tcp_may_send_now and tcp_snd_test that are no longer used

Fixes: 840a3cbe89 ("tcp: remove forward retransmit feature")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 17:26:11 -07:00
Davide Caratti 3ff4cbec87 net/sched: cls_matchall: fix crash when used with classful qdisc
this script, edited from Linux Advanced Routing and Traffic Control guide

tc q a dev en0 root handle 1: htb default a
tc c a dev en0 parent 1:  classid 1:1 htb rate 6mbit burst 15k
tc c a dev en0 parent 1:1 classid 1:a htb rate 5mbit ceil 6mbit burst 15k
tc c a dev en0 parent 1:1 classid 1:b htb rate 1mbit ceil 6mbit burst 15k
tc f a dev en0 parent 1:0 prio 1 $clsname $clsargs classid 1:b
ping $address -c1
tc -s c s dev en0

classifies traffic to 1:b or 1:a, depending on whether the packet matches
or not the pattern $clsargs of filter $clsname. However, when $clsname is
'matchall', a systematic crash can be observed in htb_classify(). HTB and
classful qdiscs don't assign initial value to struct tcf_result, but then
they expect it to contain valid values after filters have been run. Thus,
current 'matchall' ignores the TCA_MATCHALL_CLASSID attribute, configured
by user, and makes HTB (and classful qdiscs) dereference random pointers.

By assigning head->res to *res in mall_classify(), before the actions are
invoked, we fix this crash and enable TCA_MATCHALL_CLASSID functionality,
that had no effect on 'matchall' classifier since its first introduction.

BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1460213
Reported-by: Jiri Benc <jbenc@redhat.com>
Fixes: b87f7936a9 ("net/sched: introduce Match-all classifier")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Yotam Gigi <yotamg@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 16:37:36 -07:00
Xin Long 8c22dab03a ip6_tunnel: do not allow loading ip6_tunnel if ipv6 is disabled in cmdline
If ipv6 has been disabled from cmdline since kernel started, it makes
no sense to allow users to create any ip6 tunnel. Otherwise, it could
some potential problem.

Jianlin found a kernel crash caused by this in ip6_gre when he set
ipv6.disable=1 in grub:

[  209.588865] Unable to handle kernel paging request for data at address 0x00000080
[  209.588872] Faulting instruction address: 0xc000000000a3aa6c
[  209.588879] Oops: Kernel access of bad area, sig: 11 [#1]
[  209.589062] NIP [c000000000a3aa6c] fib_rules_lookup+0x4c/0x260
[  209.589071] LR [c000000000b9ad90] fib6_rule_lookup+0x50/0xb0
[  209.589076] Call Trace:
[  209.589097] fib6_rule_lookup+0x50/0xb0
[  209.589106] rt6_lookup+0xc4/0x110
[  209.589116] ip6gre_tnl_link_config+0x214/0x2f0 [ip6_gre]
[  209.589125] ip6gre_newlink+0x138/0x3a0 [ip6_gre]
[  209.589134] rtnl_newlink+0x798/0xb80
[  209.589142] rtnetlink_rcv_msg+0xec/0x390
[  209.589151] netlink_rcv_skb+0x138/0x150
[  209.589159] rtnetlink_rcv+0x48/0x70
[  209.589169] netlink_unicast+0x538/0x640
[  209.589175] netlink_sendmsg+0x40c/0x480
[  209.589184] ___sys_sendmsg+0x384/0x4e0
[  209.589194] SyS_sendmsg+0xd4/0x140
[  209.589201] SyS_socketcall+0x3e0/0x4f0
[  209.589209] system_call+0x38/0xe0

This patch is to return -EOPNOTSUPP in ip6_tunnel_init if ipv6 has been
disabled from cmdline.

Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 16:34:32 -07:00
Xin Long 76cc0d3282 ip6_gre: skb_push ipv6hdr before packing the header in ip6gre_header
Now in ip6gre_header before packing the ipv6 header, it skb_push t->hlen
which only includes encap_hlen + tun_hlen. It means greh and inner header
would be over written by ipv6 stuff and ipv6h might have no chance to set
up.

Jianlin found this issue when using remote any on ip6_gre, the packets he
captured on gre dev are truncated:

22:50:26.210866 Out ethertype IPv6 (0x86dd), length 120: truncated-ip6 -\
8128 bytes missing!(flowlabel 0x92f40, hlim 0, next-header Options (0)  \
payload length: 8192) ::1:2000:0 > ::1:0:86dd: HBH [trunc] ip-proto-128 \
8184

It should also skb_push ipv6hdr so that ipv6h points to the right position
to set ipv6 stuff up.

This patch is to skb_push hlen + sizeof(*ipv6h) and also fix some indents
in ip6gre_header.

Fixes: c12b395a46 ("gre: Support GRE over IPv6")
Reported-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 14:50:45 -07:00
Johannes Berg 265698d7e6 nl80211: fix null-ptr dereference on invalid mesh configuration
If TX rates are specified during mesh join, the channel must
also be specified. Check the channel pointer to avoid a null
pointer dereference if it isn't.

Reported-by: Jouni Malinen <j@w1.fi>
Fixes: 8564e38206 ("cfg80211: add checks for beacon rate, extend to mesh")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-09-18 22:51:07 +02:00
Subash Abhinov Kasiviswanathan 63ecc3d943 udpv6: Fix the checksum computation when HW checksum does not apply
While trying an ESP transport mode encryption for UDPv6 packets of
datagram size 1436 with MTU 1500, checksum error was observed in
the secondary fragment.

This error occurs due to the UDP payload checksum being missed out
when computing the full checksum for these packets in
udp6_hwcsum_outgoing().

Fixes: d39d938c82 ("ipv6: Introduce udpv6_send_skb()")
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-18 11:43:03 -07:00
Linus Torvalds 48bddb143b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix hotplug deadlock in hv_netvsc, from Stephen Hemminger.

 2) Fix double-free in rmnet driver, from Dan Carpenter.

 3) INET connection socket layer can double put request sockets, fix
    from Eric Dumazet.

 4) Don't match collect metadata-mode tunnels if the device is down,
    from Haishuang Yan.

 5) Do not perform TSO6/GSO on ipv6 packets with extensions headers in
    be2net driver, from Suresh Reddy.

 6) Fix scaling error in gen_estimator, from Eric Dumazet.

 7) Fix 64-bit statistics deadlock in systemport driver, from Florian
    Fainelli.

 8) Fix use-after-free in sctp_sock_dump, from Xin Long.

 9) Reject invalid BPF_END instructions in verifier, from Edward Cree.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (43 commits)
  mlxsw: spectrum_router: Only handle IPv4 and IPv6 events
  Documentation: link in networking docs
  tcp: fix data delivery rate
  bpf/verifier: reject BPF_ALU64|BPF_END
  sctp: do not mark sk dumped when inet_sctp_diag_fill returns err
  sctp: fix an use-after-free issue in sctp_sock_dump
  netvsc: increase default receive buffer size
  tcp: update skb->skb_mstamp more carefully
  net: ipv4: fix l3slave check for index returned in IP_PKTINFO
  net: smsc911x: Quieten netif during suspend
  net: systemport: Fix 64-bit stats deadlock
  net: vrf: avoid gcc-4.6 warning
  qed: remove unnecessary call to memset
  tg3: clean up redundant initialization of tnapi
  tls: make tls_sw_free_resources static
  sctp: potential read out of bounds in sctp_ulpevent_type_enabled()
  MAINTAINERS: review Renesas DT bindings as well
  net_sched: gen_estimator: fix scaling error in bytes/packets samples
  nfp: wait for the NSP resource to appear on boot
  nfp: wait for board state before talking to the NSP
  ...
2017-09-16 11:28:59 -07:00
Eric Dumazet fc22579917 tcp: fix data delivery rate
Now skb->mstamp_skb is updated later, we also need to call
tcp_rate_skb_sent() after the update is done.

Fixes: 8c72c65b42 ("tcp: update skb->skb_mstamp more carefully")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-16 09:07:01 -07:00
Xin Long 8c7c19a55e sctp: do not mark sk dumped when inet_sctp_diag_fill returns err
sctp_diag would not actually dump out sk/asoc if inet_sctp_diag_fill
returns err, in which case it shouldn't mark sk dumped by setting
cb->args[3] as 1 in sctp_sock_dump().

Otherwise, it could cause some asocs to have no parent's sk dumped
in 'ss --sctp'.

So this patch is to not set cb->args[3] when inet_sctp_diag_fill()
returns err in sctp_sock_dump().

Fixes: 8f840e47f1 ("sctp: add the sctp_diag.c file")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-15 14:51:15 -07:00
Xin Long d25adbeb0c sctp: fix an use-after-free issue in sctp_sock_dump
Commit 86fdb3448c ("sctp: ensure ep is not destroyed before doing the
dump") tried to fix an use-after-free issue by checking !sctp_sk(sk)->ep
with holding sock and sock lock.

But Paolo noticed that endpoint could be destroyed in sctp_rcv without
sock lock protection. It means the use-after-free issue still could be
triggered when sctp_rcv put and destroy ep after sctp_sock_dump checks
!ep, although it's pretty hard to reproduce.

I could reproduce it by mdelay in sctp_rcv while msleep in sctp_close
and sctp_sock_dump long time.

This patch is to add another param cb_done to sctp_for_each_transport
and dump ep->assocs with holding tsp after jumping out of transport's
traversal in it to avoid this issue.

It can also improve sctp diag dump to make it run faster, as no need
to save sk into cb->args[5] and keep calling sctp_for_each_transport
any more.

This patch is also to use int * instead of int for the pos argument
in sctp_for_each_transport, which could make postion increment only
in sctp_for_each_transport and no need to keep changing cb->args[2]
in sctp_sock_filter and sctp_sock_dump any more.

Fixes: 86fdb3448c ("sctp: ensure ep is not destroyed before doing the dump")
Reported-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-15 14:47:49 -07:00
Eric Dumazet 8c72c65b42 tcp: update skb->skb_mstamp more carefully
liujian reported a problem in TCP_USER_TIMEOUT processing with a patch
in tcp_probe_timer() :
      https://www.spinics.net/lists/netdev/msg454496.html

After investigations, the root cause of the problem is that we update
skb->skb_mstamp of skbs in write queue, even if the attempt to send a
clone or copy of it failed. One reason being a routing problem.

This patch prevents this, solving liujian issue.

It also removes a potential RTT miscalculation, since
__tcp_retransmit_skb() is not OR-ing TCP_SKB_CB(skb)->sacked with
TCPCB_EVER_RETRANS if a failure happens, but skb->skb_mstamp has
been changed.

A future ACK would then lead to a very small RTT sample and min_rtt
would then be lowered to this too small value.

Tested:

# cat user_timeout.pkt
--local_ip=192.168.102.64

    0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3
   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
   +0 bind(3, ..., ...) = 0
   +0 listen(3, 1) = 0

   +0 `ifconfig tun0 192.168.102.64/16; ip ro add 192.0.2.1 dev tun0`

   +0 < S 0:0(0) win 0 <mss 1460>
   +0 > S. 0:0(0) ack 1 <mss 1460>

  +.1 < . 1:1(0) ack 1 win 65530
   +0 accept(3, ..., ...) = 4

   +0 setsockopt(4, SOL_TCP, TCP_USER_TIMEOUT, [3000], 4) = 0
   +0 write(4, ..., 24) = 24
   +0 > P. 1:25(24) ack 1 win 29200
   +.1 < . 1:1(0) ack 25 win 65530

//change the ipaddress
   +1 `ifconfig tun0 192.168.0.10/16`

   +1 write(4, ..., 24) = 24
   +1 write(4, ..., 24) = 24
   +1 write(4, ..., 24) = 24
   +1 write(4, ..., 24) = 24

   +0 `ifconfig tun0 192.168.102.64/16`
   +0 < . 1:2(1) ack 25 win 65530
   +0 `ifconfig tun0 192.168.0.10/16`

   +3 write(4, ..., 24) = -1

# ./packetdrill user_timeout.pkt

Signed-off-by: Eric Dumazet <edumazet@googl.com>
Reported-by: liujian <liujian56@huawei.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-15 14:36:28 -07:00
David Ahern cbea8f0206 net: ipv4: fix l3slave check for index returned in IP_PKTINFO
rt_iif is only set to the actual egress device for the output path. The
recent change to consider the l3slave flag when returning IP_PKTINFO
works for local traffic (the correct device index is returned), but it
broke the more typical use case of packets received from a remote host
always returning the VRF index rather than the original ingress device.
Update the fixup to consider l3slave and rt_iif actually getting set.

Fixes: 1dfa76390b ("net: ipv4: add check for l3slave for index returned in IP_PKTINFO")
Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-15 14:27:51 -07:00
Vladis Dronov e785fa0a16 nl80211: check for the required netlink attributes presence
nl80211_set_rekey_data() does not check if the required attributes
NL80211_REKEY_DATA_{REPLAY_CTR,KEK,KCK} are present when processing
NL80211_CMD_SET_REKEY_OFFLOAD request. This request can be issued by
users with CAP_NET_ADMIN privilege and may result in NULL dereference
and a system crash. Add a check for the required attributes presence.
This patch is based on the patch by bo Zhang.

This fixes CVE-2017-12153.

References: https://bugzilla.redhat.com/show_bug.cgi?id=1491046
Fixes: e5497d766a ("cfg80211/nl80211: support GTK rekey offload")
Cc: <stable@vger.kernel.org> # v3.1-rc1
Reported-by: bo Zhang <zhangbo5891001@gmail.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-09-15 09:15:14 +02:00
Linus Torvalds 581bfce969 Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull more set_fs removal from Al Viro:
 "Christoph's 'use kernel_read and friends rather than open-coding
  set_fs()' series"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: unexport vfs_readv and vfs_writev
  fs: unexport vfs_read and vfs_write
  fs: unexport __vfs_read/__vfs_write
  lustre: switch to kernel_write
  gadget/f_mass_storage: stop messing with the address limit
  mconsole: switch to kernel_read
  btrfs: switch write_buf to kernel_write
  net/9p: switch p9_fd_read to kernel_write
  mm/nommu: switch do_mmap_private to kernel_read
  serial2002: switch serial2002_tty_write to kernel_{read/write}
  fs: make the buf argument to __kernel_write a void pointer
  fs: fix kernel_write prototype
  fs: fix kernel_read prototype
  fs: move kernel_read to fs/read_write.c
  fs: move kernel_write to fs/read_write.c
  autofs4: switch autofs4_write to __kernel_write
  ashmem: switch to ->read_iter
2017-09-14 18:13:32 -07:00
Tobias Klauser a5135676bb tls: make tls_sw_free_resources static
Make the needlessly global function tls_sw_free_resources static to fix
a gcc/sparse warning.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-14 09:55:21 -07:00
Eric Dumazet ca558e1859 net_sched: gen_estimator: fix scaling error in bytes/packets samples
Denys reported wrong rate estimations with HTB classes.

It appears the bug was added in linux-4.10, since my tests
where using intervals of one second only.

HTB using 4 sec default rate estimators, reported rates
were 4x higher.

We need to properly scale the bytes/packets samples before
integrating them in EWMA.

Tested:
 echo 1 >/sys/module/sch_htb/parameters/htb_rate_est

 Setup HTB with one class with a rate/cail of 5Gbit

 Generate traffic on this class

 tc -s -d cl sh dev eth0 classid 7002:11
class htb 7002:11 parent 7002:1 prio 5 quantum 200000 rate 5Gbit ceil
5Gbit linklayer ethernet burst 80000b/1 mpu 0b cburst 80000b/1 mpu 0b
level 0 rate_handle 1
 Sent 1488215421648 bytes 982969243 pkt (dropped 0, overlimits 0
requeues 0)
 rate 5Gbit 412814pps backlog 136260b 2p requeues 0
 TCP pkts/rtx 982969327/45 bytes 1488215557414/68130
 lended: 22732826 borrowed: 0 giants: 0
 tokens: -1684 ctokens: -1684

Fixes: 1c0d32fde5 ("net_sched: gen_estimator: complete rewrite of rate estimators")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Denys Fedoryshchenko <nuclearcat@nuclearcat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-13 13:30:53 -07:00
Jiri Pirko 255cd50f20 net: sched: fix use-after-free in tcf_action_destroy and tcf_del_walker
Recent commit d7fb60b9ca ("net_sched: get rid of tcfa_rcu") removed
freeing in call_rcu, which changed already existing hard-to-hit
race condition into 100% hit:

[  598.599825] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[  598.607782] IP: tcf_action_destroy+0xc0/0x140

Or:

[   40.858924] BUG: unable to handle kernel NULL pointer dereference at 0000000000000030
[   40.862840] IP: tcf_generic_walker+0x534/0x820

Fix this by storing the ops and use them directly for module_put call.

Fixes: a85a970af2 ("net_sched: move tc_action into tcf_common")
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-13 09:34:08 -07:00
Haishuang Yan 6c1cb4393c ip6_tunnel: fix ip6 tunnel lookup in collect_md mode
In collect_md mode, if the tun dev is down, it still can call
__ip6_tnl_rcv to receive on packets, and the rx statistics increase
improperly.

When the md tunnel is down, it's not neccessary to increase RX drops
for the tunnel device, packets would be recieved on fallback tunnel,
and the RX drops on fallback device will be increased as expected.

Fixes: 8d79266bc4 ("ip6_tunnel: add collect_md mode to IPv6 tunnels")
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:45:31 -07:00
Haishuang Yan 833a8b4054 ip_tunnel: fix ip tunnel lookup in collect_md mode
In collect_md mode, if the tun dev is down, it still can call
ip_tunnel_rcv to receive on packets, and the rx statistics increase
improperly.

When the md tunnel is down, it's not neccessary to increase RX drops
for the tunnel device, packets would be recieved on fallback tunnel,
and the RX drops on fallback device will be increased as expected.

Fixes: 2e15ea390e ("ip_gre: Add support to collect tunnel metadata.")
Cc: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:45:31 -07:00
Cong Wang 1697c4bb52 net_sched: carefully handle tcf_block_put()
As pointed out by Jiri, there is still a race condition between
tcf_block_put() and tcf_chain_destroy() in a RCU callback. There
is no way to make it correct without proper locking or synchronization,
because both operate on a shared list.

Locking is hard, because the only lock we can pick here is a spinlock,
however, in tc_dump_tfilter() we iterate this list with a sleeping
function called (tcf_chain_dump()), which makes using a lock to protect
chain_list almost impossible.

Jiri suggested the idea of holding a refcnt before flushing, this works
because it guarantees us there would be no parallel tcf_chain_destroy()
during the loop, therefore the race condition is gone. But we have to
be very careful with proper synchronization with RCU callbacks.

Suggested-by: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Cong Wang e2ef754453 net_sched: fix reference counting of tc filter chain
This patch fixes the following ugliness of tc filter chain refcnt:

a) tp proto should hold a refcnt to the chain too. This significantly
   simplifies the logic.

b) Chain 0 is no longer special, it is created with refcnt=1 like any
   other chains. All the ugliness in tcf_chain_put() can be gone!

c) No need to handle the flushing oddly, because block still holds
   chain 0, it can not be released, this guarantees block is the last
   user.

d) The race condition with RCU callbacks is easier to handle with just
   a rcu_barrier(). Much easier to understand, nothing to hide. Thanks
   to the previous patch. Please see also the comments in code.

e) Make the code understandable by humans, much less error-prone.

Fixes: 744a4cf63e ("net: sched: fix use after free when tcf_chain_destroy is called multiple times")
Fixes: 5bc1701881 ("net: sched: introduce multichain support for filters")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Cong Wang d7fb60b9ca net_sched: get rid of tcfa_rcu
gen estimator has been rewritten in commit 1c0d32fde5
("net_sched: gen_estimator: complete rewrite of rate estimators"),
the caller is no longer needed to wait for a grace period.
So this patch gets rid of it.

This also completely closes a race condition between action free
path and filter chain add/remove path for the following patch.
Because otherwise the nested RCU callback can't be caught by
rcu_barrier().

Please see also the comments in code.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:41:02 -07:00
Eric Dumazet da8ab57863 tcp/dccp: remove reqsk_put() from inet_child_forget()
Back in linux-4.4, I inadvertently put a call to reqsk_put() in
inet_child_forget(), forgetting it could be called from two different
points.

In the case it is called from inet_csk_reqsk_queue_add(), we want to
keep the reference on the request socket, since it is released later by
the caller (tcp_v{4|6}_rcv())

This bug never showed up because atomic_dec_and_test() was not signaling
the underflow, and SLAB_DESTROY_BY RCU semantic for request sockets
prevented the request to be put in quarantine.

Recent conversion of socket refcount from atomic_t to refcount_t finally
exposed the bug.

So move the reqsk_put() to inet_csk_listen_stop() to fix this.

Thanks to Shankara Pailoor for using syzkaller and providing
a nice set of .config and C repro.

WARNING: CPU: 2 PID: 4277 at lib/refcount.c:186
refcount_sub_and_test+0x167/0x1b0 lib/refcount.c:186
Kernel panic - not syncing: panic_on_warn set ...

CPU: 2 PID: 4277 Comm: syz-executor0 Not tainted 4.13.0-rc7 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
Ubuntu-1.8.2-1ubuntu1 04/01/2014
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0xf7/0x1aa lib/dump_stack.c:52
 panic+0x1ae/0x3a7 kernel/panic.c:180
 __warn+0x1c4/0x1d9 kernel/panic.c:541
 report_bug+0x211/0x2d0 lib/bug.c:183
 fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:190
 do_trap_no_signal arch/x86/kernel/traps.c:224 [inline]
 do_trap+0x260/0x390 arch/x86/kernel/traps.c:273
 do_error_trap+0x118/0x340 arch/x86/kernel/traps.c:310
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:323
 invalid_op+0x18/0x20 arch/x86/entry/entry_64.S:846
RIP: 0010:refcount_sub_and_test+0x167/0x1b0 lib/refcount.c:186
RSP: 0018:ffff88006e006b60 EFLAGS: 00010286
RAX: 0000000000000026 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000026 RSI: 1ffff1000dc00d2c RDI: ffffed000dc00d60
RBP: ffff88006e006bf0 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 1ffff1000dc00d6d
R13: 00000000ffffffff R14: 0000000000000001 R15: ffff88006ce9d340
 refcount_dec_and_test+0x1a/0x20 lib/refcount.c:211
 reqsk_put+0x71/0x2b0 include/net/request_sock.h:123
 tcp_v4_rcv+0x259e/0x2e20 net/ipv4/tcp_ipv4.c:1729
 ip_local_deliver_finish+0x2e2/0xba0 net/ipv4/ip_input.c:216
 NF_HOOK include/linux/netfilter.h:248 [inline]
 ip_local_deliver+0x1ce/0x6d0 net/ipv4/ip_input.c:257
 dst_input include/net/dst.h:477 [inline]
 ip_rcv_finish+0x8db/0x19c0 net/ipv4/ip_input.c:397
 NF_HOOK include/linux/netfilter.h:248 [inline]
 ip_rcv+0xc3f/0x17d0 net/ipv4/ip_input.c:488
 __netif_receive_skb_core+0x1fb7/0x31f0 net/core/dev.c:4298
 __netif_receive_skb+0x2c/0x1b0 net/core/dev.c:4336
 process_backlog+0x1c5/0x6d0 net/core/dev.c:5102
 napi_poll net/core/dev.c:5499 [inline]
 net_rx_action+0x6d3/0x14a0 net/core/dev.c:5565
 __do_softirq+0x2cb/0xb2d kernel/softirq.c:284
 do_softirq_own_stack+0x1c/0x30 arch/x86/entry/entry_64.S:898
 </IRQ>
 do_softirq.part.16+0x63/0x80 kernel/softirq.c:328
 do_softirq kernel/softirq.c:176 [inline]
 __local_bh_enable_ip+0x84/0x90 kernel/softirq.c:181
 local_bh_enable include/linux/bottom_half.h:31 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:705 [inline]
 ip_finish_output2+0x8ad/0x1360 net/ipv4/ip_output.c:231
 ip_finish_output+0x74e/0xb80 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:237 [inline]
 ip_output+0x1cc/0x850 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:471 [inline]
 ip_local_out+0x95/0x160 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x8c6/0x1810 net/ipv4/ip_output.c:504
 tcp_transmit_skb+0x1963/0x3320 net/ipv4/tcp_output.c:1123
 tcp_send_ack.part.35+0x38c/0x620 net/ipv4/tcp_output.c:3575
 tcp_send_ack+0x49/0x60 net/ipv4/tcp_output.c:3545
 tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:5795 [inline]
 tcp_rcv_state_process+0x4876/0x4b60 net/ipv4/tcp_input.c:5930
 tcp_v4_do_rcv+0x58a/0x820 net/ipv4/tcp_ipv4.c:1483
 sk_backlog_rcv include/net/sock.h:907 [inline]
 __release_sock+0x124/0x360 net/core/sock.c:2223
 release_sock+0xa4/0x2a0 net/core/sock.c:2715
 inet_wait_for_connect net/ipv4/af_inet.c:557 [inline]
 __inet_stream_connect+0x671/0xf00 net/ipv4/af_inet.c:643
 inet_stream_connect+0x58/0xa0 net/ipv4/af_inet.c:682
 SYSC_connect+0x204/0x470 net/socket.c:1628
 SyS_connect+0x24/0x30 net/socket.c:1609
 entry_SYSCALL_64_fastpath+0x18/0xad
RIP: 0033:0x451e59
RSP: 002b:00007f474843fc08 EFLAGS: 00000216 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 0000000000451e59
RDX: 0000000000000010 RSI: 0000000020002000 RDI: 0000000000000007
RBP: 0000000000000046 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 0000000000000000
R13: 00007ffc040a0f8f R14: 00007f47484409c0 R15: 0000000000000000

Fixes: ebb516af60 ("tcp/dccp: fix race at listener dismantle phase")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Shankara Pailoor <sp3485@columbia.edu>
Tested-by: Shankara Pailoor <sp3485@columbia.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:38:35 -07:00
Christophe JAILLET 5829e62ac1 openvswitch: Fix an error handling path in 'ovs_nla_init_match_and_action()'
All other error handling paths in this function go through the 'error'
label. This one should do the same.

Fixes: 9cc9a5cb17 ("datapath: Avoid using stack larger than 1024.")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-12 20:37:31 -07:00
Linus Torvalds cdb897e327 The highlights include:
* a large series of fixes and improvements to the snapshot-handling
    code (Zheng Yan)
 
  * individual read/write OSD requests passed down to libceph are now
    limited to 16M in size to avoid hitting OSD-side limits (Zheng Yan)
 
  * encode MStatfs v2 message to allow for more accurate space usage
    reporting (Douglas Fuller)
 
  * switch to the new writeback error tracking infrastructure (Jeff
    Layton)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v2
 
 iQEcBAABCAAGBQJZuAC0AAoJEEp/3jgCEfOLb14H/REYq4fDDkUa70L4leKWWdCa
 n71ipkKeoorfivts71iOtGMJfK+Z6ax+dq1PvBWMy6PtzXS/+2B+t2XwILvLiwWH
 h87i44bY68aLWRTSusgTfB+I7gyVrWN0WMLznZ5rfM9XuyPv+RPyJYh3EhxWI5+U
 2kOHFEc+cPL6mAshGmB8lIzKOWTfmBiw28ulICwlcazm79hh39aNBQE546lS8gA3
 kXuJ55odojPgXOYh+vs60raIBnm6flek1jLxBGYG3MU4gv0VVWOyW0eWeuqW+EcR
 6dVYlzg1xGlPp+vRmDZQuv/E2MafBxdcil/RrdLeqcx/Hf1KJBzcLgUzIMbnOAI=
 =YDZP
 -----END PGP SIGNATURE-----

Merge tag 'ceph-for-4.14-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "The highlights include:

   - a large series of fixes and improvements to the snapshot-handling
     code (Zheng Yan)

   - individual read/write OSD requests passed down to libceph are now
     limited to 16M in size to avoid hitting OSD-side limits (Zheng Yan)

   - encode MStatfs v2 message to allow for more accurate space usage
     reporting (Douglas Fuller)

   - switch to the new writeback error tracking infrastructure (Jeff
     Layton)"

* tag 'ceph-for-4.14-rc1' of git://github.com/ceph/ceph-client: (35 commits)
  ceph: stop on-going cached readdir if mds revokes FILE_SHARED cap
  ceph: wait on writeback after writing snapshot data
  ceph: fix capsnap dirty pages accounting
  ceph: ignore wbc->range_{start,end} when write back snapshot data
  ceph: fix "range cyclic" mode writepages
  ceph: cleanup local variables in ceph_writepages_start()
  ceph: optimize pagevec iterating in ceph_writepages_start()
  ceph: make writepage_nounlock() invalidate page that beyonds EOF
  ceph: properly get capsnap's size in get_oldest_context()
  ceph: remove stale check in ceph_invalidatepage()
  ceph: queue cap snap only when snap realm's context changes
  ceph: handle race between vmtruncate and queuing cap snap
  ceph: fix message order check in handle_cap_export()
  ceph: fix NULL pointer dereference in ceph_flush_snaps()
  ceph: adjust 36 checks for NULL pointers
  ceph: delete an unnecessary return statement in update_dentry_lease()
  ceph: ENOMEM pr_err in __get_or_create_frag() is redundant
  ceph: check negative offsets in ceph_llseek()
  ceph: more accurate statfs
  ceph: properly set snap follows for cap reconnect
  ...
2017-09-12 20:03:53 -07:00
Linus Torvalds 8e7757d83d NFS client updates for Linux 4.14
Hightlights include:
 
 Stable bugfixes:
 - Fix mirror allocation in the writeback code to avoid a use after free
 - Fix the O_DSYNC writes to use the correct byte range
 - Fix 2 use after free issues in the I/O code
 
 Features:
 - Writeback fixes to split up the inode->i_lock in order to reduce contention
 - RPC client receive fixes to reduce the amount of time the
   xprt->transport_lock is held when receiving data from a socket into am
   XDR buffer.
 - Ditto fixes to reduce contention between call side users of the rdma
   rb_lock, and its use in rpcrdma_reply_handler.
 - Re-arrange rdma stats to reduce false cacheline sharing.
 - Various rdma cleanups and optimisations.
 - Refactor the NFSv4.1 exchange id code and clean up the code.
 - Const-ify all instances of struct rpc_xprt_ops
 
 Bugfixes:
 - Fix the NFSv2 'sec=' mount option.
 - NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
 - Fix the NFSv3 GRANT callback when the port changes on the server.
 - Fix livelock issues with COMMIT
 - NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when doing
   and NFSv4.1 open by filehandle.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZtbvIAAoJEGcL54qWCgDy/boP/jRuVk6B2VyhWnJkOgdQzIN3
 Q8PIR0oxkywH2MI7c9/G2k5b/HD9BK2iQrXzIoPxRuPrckKLwzqYclzG8PR4Niyg
 D3CCzrvGcEXZrv/nHQ+HDMD0ZuUyXFqhrYeyQwNSJ9p/oP0gaxnYwteennfJVa99
 mv6+LdoY+lzVYJI1gmMHVF2zOhN+rTe7xUVnjYnsVCpwMvL+u992oZl3qQJRFG6b
 HlXOy7h5JRFyue61P20PSgh9D1JUWWYD/V0EG+7cIvByAg5KxhvVgjqSsTTT7FXe
 Omn4fTv1MFzk8er9qYFRjpM2IoIdAejFMqX3/PxQVr2qOFNmHYrq+WsdWNQEr/Wu
 WREJu5Ac1Hboe2/scA+DtuVPFePPPyrolhwk533aNWrdDywg01e0XqBEDKR/atJd
 u5lvW20UfLQuCFLOpaxDpq2ngQSOg6t96N36tsydG0SAVpiydOPMLqkQi7Nb3aoB
 79xGpmtnijP5T6jnOI2/nexM08OMTI0BhMbXJC5v1+lnxIJKcKdnGlTM4UJyxUMq
 /3dFI4IQZLfkMEjIvZFoi+nKWx3DYhiUhkKhbBYwtB4P4q8Z2qKTPHFxORz9griZ
 Pa+8BPuDuodIWuDD97q1Dnw2NWjQim8Rx/ce4c8FHGzwMJLPkcVqk+guGsub5IdO
 7qF7Vvv02gJ48TAqTBDf
 =1Ssl
 -----END PGP SIGNATURE-----

Merge tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

Pull NFS client updates from Trond Myklebust:
 "Hightlights include:

  Stable bugfixes:
   - Fix mirror allocation in the writeback code to avoid a use after
     free
   - Fix the O_DSYNC writes to use the correct byte range
   - Fix 2 use after free issues in the I/O code

  Features:
   - Writeback fixes to split up the inode->i_lock in order to reduce
     contention
   - RPC client receive fixes to reduce the amount of time the
     xprt->transport_lock is held when receiving data from a socket into
     am XDR buffer.
   - Ditto fixes to reduce contention between call side users of the
     rdma rb_lock, and its use in rpcrdma_reply_handler.
   - Re-arrange rdma stats to reduce false cacheline sharing.
   - Various rdma cleanups and optimisations.
   - Refactor the NFSv4.1 exchange id code and clean up the code.
   - Const-ify all instances of struct rpc_xprt_ops

  Bugfixes:
   - Fix the NFSv2 'sec=' mount option.
   - NFSv4.1: don't use machine credentials for CLOSE when using
     'sec=sys'
   - Fix the NFSv3 GRANT callback when the port changes on the server.
   - Fix livelock issues with COMMIT
   - NFSv4: Use correct inode in _nfs4_opendata_to_nfs4_state() when
     doing and NFSv4.1 open by filehandle"

* tag 'nfs-for-4.14-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (69 commits)
  NFS: Count the bytes of skipped subrequests in nfs_lock_and_join_requests()
  NFS: Don't hold the group lock when calling nfs_release_request()
  NFS: Remove pnfs_generic_transfer_commit_list()
  NFS: nfs_lock_and_join_requests and nfs_scan_commit_list can deadlock
  NFS: Fix 2 use after free issues in the I/O code
  NFS: Sync the correct byte range during synchronous writes
  lockd: Delete an error message for a failed memory allocation in reclaimer()
  NFS: remove jiffies field from access cache
  NFS: flush data when locking a file to ensure cache coherence for mmap.
  SUNRPC: remove some dead code.
  NFS: don't expect errors from mempool_alloc().
  xprtrdma: Use xprt_pin_rqst in rpcrdma_reply_handler
  xprtrdma: Re-arrange struct rx_stats
  NFS: Fix NFSv2 security settings
  NFSv4.1: don't use machine credentials for CLOSE when using 'sec=sys'
  SUNRPC: ECONNREFUSED should cause a rebind.
  NFS: Remove unused parameter gfp_flags from nfs_pageio_init()
  NFSv4: Fix up mirror allocation
  SUNRPC: Add a separate spinlock to protect the RPC request receive list
  SUNRPC: Cleanup xs_tcp_read_common()
  ...
2017-09-11 22:01:44 -07:00
Josh Hunt 230cfd2dbc net/sched: fix pointer check in gen_handle
Fixes sparse warning about pointer in gen_handle:
net/sched/cls_rsvp.h:392:40: warning: Using plain integer as NULL pointer

Fixes: 8113c09567 ("net_sched: use void pointer for filter handle")
Signed-off-by: Josh Hunt <johunt@akamai.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-11 14:34:52 -07:00
David Lebrun 33e34e735f ipv6: sr: remove duplicate routing header type check
As seg6_validate_srh() already checks that the Routing Header type is
correct, it is not necessary to do it again in get_srh().

Fixes: 5829d70b ("ipv6: sr: fix get_srh() to comply with IPv6 standard "RFC 8200")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-11 14:34:10 -07:00
Jesper Dangaard Brouer 96c5508e30 xdp: implement xdp_redirect_map for generic XDP
Using bpf_redirect_map is allowed for generic XDP programs, but the
appropriate map lookup was never performed in xdp_do_generic_redirect().

Instead the map-index is directly used as the ifindex.  For the
xdp_redirect_map sample in SKB-mode '-S', this resulted in trying
sending on ifindex 0 which isn't valid, resulting in getting SKB
packets dropped.  Thus, the reported performance numbers are wrong in
commit 24251c2647 ("samples/bpf: add option for native and skb mode
for redirect apps") for the 'xdp_redirect_map -S' case.

Before commit 109980b894 ("bpf: don't select potentially stale
ri->map from buggy xdp progs") it could crash the kernel.  Like this
commit also check that the map_owner owner is correct before
dereferencing the map pointer.  But make sure that this API misusage
can be caught by a tracepoint. Thus, allowing userspace via
tracepoints to detect misbehaving bpf_progs.

Fixes: 6103aa96ec ("net: implement XDP_REDIRECT for xdp generic")
Fixes: 24251c2647 ("samples/bpf: add option for native and skb mode for redirect apps")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-11 14:33:00 -07:00
Ben Seri e860d2c904 Bluetooth: Properly check L2CAP config option output buffer length
Validate the output buffer length for L2CAP config requests and responses
to avoid overflowing the stack buffer used for building the option blocks.

Cc: stable@vger.kernel.org
Signed-off-by: Ben Seri <ben@armis.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-09-09 17:56:05 -07:00
Linus Torvalds ad9a19d003 More RDMA work and some op-structure constification from Chuck Lever,
and a small cleanup to our xdr encoding.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJZst0LAAoJECebzXlCjuG+o30QALbchoIvs7BiDrUxYMfJ2nCa
 7UW69STwX79B3NZTg7RrScFTLPEFW9DMpb/Og7AYTH3/wdgGYQNM1UxGUYe7IxSN
 xemH7BSmQzJ7ryaxouO/jskUw5nvNRXhY0PMxJApjrCs837vTjduIVw9zUa8EDeH
 9toxpTM4k3z/1myj60PuHnuQF9EyLDL6W581loDF04nQB3pVRbAZOh1lUeqMgLUd
 7IF+CDECFcjL7oZSA3wDGpsVySLdZ+GYxloFIDO/d8kHEsZD3OaN2MdfRki8EOSQ
 qibTYO0284VeyNLUOIHjspqbDh0Lr2F7VolMmlM5GF1IuApih0/QYidqsH6/As3U
 JIAK53vgqZfK2qI0ud7dGGFEnT/vlE7pQiXiza36xI8YZu4Xz6uGbM41p38RU8jO
 3fr38xdPqqO7YE6F7ZUHYyrmW81Vi0lFdQkw1DBEipHV8UquuCmdtAeR9xgDsdQ/
 LsMVevM1mF+19krOIGbBnENq1GX78ecfHEYGxlTjf/MeO4JYl+8/x7Ow2e/ZbwSa
 7hpUeCiVuVmy1hqOEtraBl5caAG0hCE8PeGRrdr5dA6ZS9YTm0ANgtxndKabwDh2
 CjXF3gRnQNUGdFGCi/fmvfb89tVNj1tL52pbQqfgOb/VFrrL328vyNNg/1p2VY4Q
 qzmKtxZhi/XBewQjaSQl
 =E3UQ
 -----END PGP SIGNATURE-----

Merge tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux

Pull nfsd updates from Bruce Fields:
 "More RDMA work and some op-structure constification from Chuck Lever,
  and a small cleanup to our xdr encoding"

* tag 'nfsd-4.14' of git://linux-nfs.org/~bfields/linux:
  svcrdma: Estimate Send Queue depth properly
  rdma core: Add rdma_rw_mr_payload()
  svcrdma: Limit RQ depth
  svcrdma: Populate tail iovec when receiving
  nfsd: Incoming xdr_bufs may have content in tail buffer
  svcrdma: Clean up svc_rdma_build_read_chunk()
  sunrpc: Const-ify struct sv_serv_ops
  nfsd: Const-ify NFSv4 encoding and decoding ops arrays
  sunrpc: Const-ify instances of struct svc_xprt_ops
  nfsd4: individual encoders no longer see error cases
  nfsd4: skip encoder in trivial error cases
  nfsd4: define ->op_release for compound ops
  nfsd4: opdesc will be useful outside nfs4proc.c
  nfsd4: move some nfsd4 op definitions to xdr4.h
2017-09-09 13:31:49 -07:00
Linus Torvalds fbd01410e8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "The iwlwifi firmware compat fix is in here as well as some other
  stuff:

  1) Fix request socket leak introduced by BPF deadlock fix, from Eric
     Dumazet.

  2) Fix VLAN handling with TXQs in mac80211, from Johannes Berg.

  3) Missing __qdisc_drop conversions in prio and qfq schedulers, from
     Gao Feng.

  4) Use after free in netlink nlk groups handling, from Xin Long.

  5) Handle MTU update properly in ipv6 gre tunnels, from Xin Long.

  6) Fix leak of ipv6 fib tables on netns teardown, from Sabrina Dubroca
     with follow-on fix from Eric Dumazet.

  7) Need RCU and preemption disabled during generic XDP data patch,
     from John Fastabend"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (54 commits)
  bpf: make error reporting in bpf_warn_invalid_xdp_action more clear
  Revert "mdio_bus: Remove unneeded gpiod NULL check"
  bpf: devmap, use cond_resched instead of cpu_relax
  bpf: add support for sockmap detach programs
  net: rcu lock and preempt disable missing around generic xdp
  bpf: don't select potentially stale ri->map from buggy xdp progs
  net: tulip: Constify tulip_tbl
  net: ethernet: ti: netcp_core: no need in netif_napi_del
  davicom: Display proper debug level up to 6
  net: phy: sfp: rename dt properties to match the binding
  dt-binding: net: sfp binding documentation
  dt-bindings: add SFF vendor prefix
  dt-bindings: net: don't confuse with generic PHY property
  ip6_tunnel: fix setting hop_limit value for ipv6 tunnel
  ip_tunnel: fix setting ttl and tos value in collect_md mode
  ipv6: fix typo in fib6_net_exit()
  tcp: fix a request socket leak
  sctp: fix missing wake ups in some situations
  netfilter: xt_hashlimit: fix build error caused by 64bit division
  netfilter: xt_hashlimit: alloc hashtable with right size
  ...
2017-09-09 11:05:20 -07:00
Daniel Borkmann 9beb8bedb0 bpf: make error reporting in bpf_warn_invalid_xdp_action more clear
Differ between illegal XDP action code and just driver
unsupported one to provide better feedback when we throw
a one-time warning here. Reason is that with 814abfabef
("xdp: add bpf_redirect helper function") not all drivers
support the new XDP return code yet and thus they will
fall into their 'default' case when checking for return
codes after program return, which then triggers a
bpf_warn_invalid_xdp_action() stating that the return
code is illegal, but from XDP perspective it's not.

I decided not to place something like a XDP_ACT_MAX define
into uapi i) given we don't have this either for all other
program types, ii) future action codes could have further
encoding there, which would render such define unsuitable
and we wouldn't be able to rip it out again, and iii) we
rarely add new action codes.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 21:13:09 -07:00
John Fastabend bbbe211c29 net: rcu lock and preempt disable missing around generic xdp
do_xdp_generic must be called inside rcu critical section with preempt
disabled to ensure BPF programs are valid and per-cpu variables used
for redirect operations are consistent. This patch ensures this is true
and fixes the splat below.

The netif_receive_skb_internal() code path is now broken into two rcu
critical sections. I decided it was better to limit the preempt_enable/disable
block to just the xdp static key portion and the fallout is more
rcu_read_lock/unlock calls. Seems like the best option to me.

[  607.596901] =============================
[  607.596906] WARNING: suspicious RCU usage
[  607.596912] 4.13.0-rc4+ #570 Not tainted
[  607.596917] -----------------------------
[  607.596923] net/core/dev.c:3948 suspicious rcu_dereference_check() usage!
[  607.596927]
[  607.596927] other info that might help us debug this:
[  607.596927]
[  607.596933]
[  607.596933] rcu_scheduler_active = 2, debug_locks = 1
[  607.596938] 2 locks held by pool/14624:
[  607.596943]  #0:  (rcu_read_lock_bh){......}, at: [<ffffffff95445ffd>] ip_finish_output2+0x14d/0x890
[  607.596973]  #1:  (rcu_read_lock_bh){......}, at: [<ffffffff953c8e3a>] __dev_queue_xmit+0x14a/0xfd0
[  607.597000]
[  607.597000] stack backtrace:
[  607.597006] CPU: 5 PID: 14624 Comm: pool Not tainted 4.13.0-rc4+ #570
[  607.597011] Hardware name: Dell Inc. Precision Tower 5810/0HHV7N, BIOS A17 03/01/2017
[  607.597016] Call Trace:
[  607.597027]  dump_stack+0x67/0x92
[  607.597040]  lockdep_rcu_suspicious+0xdd/0x110
[  607.597054]  do_xdp_generic+0x313/0xa50
[  607.597068]  ? time_hardirqs_on+0x5b/0x150
[  607.597076]  ? mark_held_locks+0x6b/0xc0
[  607.597088]  ? netdev_pick_tx+0x150/0x150
[  607.597117]  netif_rx_internal+0x205/0x3f0
[  607.597127]  ? do_xdp_generic+0xa50/0xa50
[  607.597144]  ? lock_downgrade+0x2b0/0x2b0
[  607.597158]  ? __lock_is_held+0x93/0x100
[  607.597187]  netif_rx+0x119/0x190
[  607.597202]  loopback_xmit+0xfd/0x1b0
[  607.597214]  dev_hard_start_xmit+0x127/0x4e0

Fixes: d445516966 ("net: xdp: support xdp generic on virtual devices")
Fixes: b5cdae3291 ("net: Generic XDP")
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 21:11:00 -07:00
Daniel Borkmann 109980b894 bpf: don't select potentially stale ri->map from buggy xdp progs
We can potentially run into a couple of issues with the XDP
bpf_redirect_map() helper. The ri->map in the per CPU storage
can become stale in several ways, mostly due to misuse, where
we can then trigger a use after free on the map:

i) prog A is calling bpf_redirect_map(), returning XDP_REDIRECT
and running on a driver not supporting XDP_REDIRECT yet. The
ri->map on that CPU becomes stale when the XDP program is unloaded
on the driver, and a prog B loaded on a different driver which
supports XDP_REDIRECT return code. prog B would have to omit
calling to bpf_redirect_map() and just return XDP_REDIRECT, which
would then access the freed map in xdp_do_redirect() since not
cleared for that CPU.

ii) prog A is calling bpf_redirect_map(), returning a code other
than XDP_REDIRECT. prog A is then detached, which triggers release
of the map. prog B is attached which, similarly as in i), would
just return XDP_REDIRECT without having called bpf_redirect_map()
and thus be accessing the freed map in xdp_do_redirect() since
not cleared for that CPU.

iii) prog A is attached to generic XDP, calling the bpf_redirect_map()
helper and returning XDP_REDIRECT. xdp_do_generic_redirect() is
currently not handling ri->map (will be fixed by Jesper), so it's
not being reset. Later loading a e.g. native prog B which would,
say, call bpf_xdp_redirect() and then returns XDP_REDIRECT would
find in xdp_do_redirect() that a map was set and uses that causing
use after free on map access.

Fix thus needs to avoid accessing stale ri->map pointers, naive
way would be to call a BPF function from drivers that just resets
it to NULL for all XDP return codes but XDP_REDIRECT and including
XDP_REDIRECT for drivers not supporting it yet (and let ri->map
being handled in xdp_do_generic_redirect()). There is a less
intrusive way w/o letting drivers call a reset for each BPF run.

The verifier knows we're calling into bpf_xdp_redirect_map()
helper, so it can do a small insn rewrite transparent to the prog
itself in the sense that it fills R4 with a pointer to the own
bpf_prog. We have that pointer at verification time anyway and
R4 is allowed to be used as per calling convention we scratch
R0 to R5 anyway, so they become inaccessible and program cannot
read them prior to a write. Then, the helper would store the prog
pointer in the current CPUs struct redirect_info. Later in
xdp_do_*_redirect() we check whether the redirect_info's prog
pointer is the same as passed xdp_prog pointer, and if that's
the case then all good, since the prog holds a ref on the map
anyway, so it is always valid at that point in time and must
have a reference count of at least 1. If in the unlikely case
they are not equal, it means we got a stale pointer, so we clear
and bail out right there. Also do reset map and the owning prog
in bpf_xdp_redirect(), so that bpf_xdp_redirect_map() and
bpf_xdp_redirect() won't get mixed up, only the last call should
take precedence. A tc bpf_redirect() doesn't use map anywhere
yet, so no need to clear it there since never accessed in that
layer.

Note that in case the prog is released, and thus the map as
well we're still under RCU read critical section at that time
and have preemption disabled as well. Once we commit with the
__dev_map_insert_ctx() from xdp_do_redirect_map() and set the
map to ri->map_to_flush, we still wait for a xdp_do_flush_map()
to finish in devmap dismantle time once flush_needed bit is set,
so that is fine.

Fixes: 97f91a7cf0 ("bpf: add bpf_redirect_map helper routine")
Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 20:58:09 -07:00
Haishuang Yan 18e1173d5f ip6_tunnel: fix setting hop_limit value for ipv6 tunnel
Similar to vxlan/geneve tunnel, if hop_limit is zero, it should fall
back to ip6_dst_hoplimt().

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 20:47:10 -07:00
Haishuang Yan 0f693f1995 ip_tunnel: fix setting ttl and tos value in collect_md mode
ttl and tos variables are declared and assigned, but are not used in
iptunnel_xmit() function.

Fixes: cfc7381b30 ("ip_tunnel: add collect_md mode to IPIP tunnel")
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 20:47:10 -07:00
Eric Dumazet 32a805baf0 ipv6: fix typo in fib6_net_exit()
IPv6 FIB should use FIB6_TABLE_HASHSZ, not FIB_TABLE_HASHSZ.

Fixes: ba1cc08d94 ("ipv6: fix memory leak with multiple tables during netns destruction")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 16:09:04 -07:00
Eric Dumazet 1f3b359f10 tcp: fix a request socket leak
While the cited commit fixed a possible deadlock, it added a leak
of the request socket, since reqsk_put() must be called if the BPF
filter decided the ACK packet must be dropped.

Fixes: d624d276d1 ("tcp: fix possible deadlock in TCP stack vs BPF filter")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 16:07:17 -07:00
David S. Miller 1080746110 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/IPVS fixes for net

The following patchset contains Netfilter/IPVS fixes for your net tree,
they are:

1) Fix SCTP connection setup when IPVS module is loaded and any scheduler
   is registered, from Xin Long.

2) Don't create a SCTP connection from SCTP ABORT packets, also from
   Xin Long.

3) WARN_ON() and drop packet, instead of BUG_ON() races when calling
   nf_nat_setup_info(). This is specifically a longstanding problem
   when br_netfilter with conntrack support is in place, patch from
   Florian Westphal.

4) Avoid softlock splats via iptables-restore, also from Florian.

5) Revert NAT hashtable conversion to rhashtable, semantics of rhlist
   are different from our simple NAT hashtable, this has been causing
   problems in the recent Linux kernel releases. From Florian.

6) Add per-bucket spinlock for NAT hashtable, so at least we restore
   one of the benefits we got from the previous rhashtable conversion.

7) Fix incorrect hashtable size in memory allocation in xt_hashlimit,
   from Zhizhou Tian.

8) Fix build/link problems with hashlimit and 32-bit arches, to address
   recent fallout from a new hashlimit mode, from Vishwanath Pai.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 11:35:55 -07:00
Marcelo Ricardo Leitner 7906b00f5c sctp: fix missing wake ups in some situations
Commit fb586f2530 ("sctp: delay calls to sk_data_ready() as much as
possible") minimized the number of wake ups that are triggered in case
the association receives a packet with multiple data chunks on it and/or
when io_events are enabled and then commit 0970f5b366 ("sctp: signal
sk_data_ready earlier on data chunks reception") moved the wake up to as
soon as possible. It thus relies on the state machine running later to
clean the flag that the event was already generated.

The issue is that there are 2 call paths that calls
sctp_ulpq_tail_event() outside of the state machine, causing the flag to
linger and possibly omitting a needed wake up in the sequence.

One of the call paths is when enabling SCTP_SENDER_DRY_EVENTS via
setsockopt(SCTP_EVENTS), as noticed by Harald Welte. The other is when
partial reliability triggers removal of chunks from the send queue when
the application calls sendmsg().

This commit fixes it by not setting the flag in case the socket is not
owned by the user, as it won't be cleaned later. This works for
user-initiated calls and also for rx path processing.

Fixes: fb586f2530 ("sctp: delay calls to sk_data_ready() as much as possible")
Reported-by: Harald Welte <laforge@gnumonks.org>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-08 10:02:47 -07:00
Vishwanath Pai 90c4ae4e2c netfilter: xt_hashlimit: fix build error caused by 64bit division
64bit division causes build/link errors on 32bit architectures. It
prints out error messages like:

ERROR: "__aeabi_uldivmod" [net/netfilter/xt_hashlimit.ko] undefined!

The value of avg passed through by userspace in BYTE mode cannot exceed
U32_MAX. Which means 64bit division in user2rate_bytes is unnecessary.
To fix this I have changed the type of param 'user' to u32.

Since anything greater than U32_MAX is an invalid input we error out in
hashlimit_mt_check_common() when this is the case.

Changes in v2:
	Making return type as u32 would cause an overflow for small
	values of 'user' (for example 2, 3 etc). To avoid this I bumped up
	'r' to u64 again as well as the return type. This is OK since the
	variable that stores the result is u64. We still avoid 64bit
	division here since 'user' is u32.

Fixes: bea74641e3 ("netfilter: xt_hashlimit: add rate match mode")
Signed-off-by: Vishwanath Pai <vpai@akamai.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:53 +02:00
Zhizhou Tian 05d0eae7c1 netfilter: xt_hashlimit: alloc hashtable with right size
struct xt_byteslimit_htable used hlist_head, but memory allocation is
done through sizeof(struct list_head).

Signed-off-by: Zhizhou Tian <zhizhou.tian@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:53 +02:00
Florian Westphal 74585d4f84 netfilter: core: remove erroneous warn_on
kernel test robot reported:

WARNING: CPU: 0 PID: 1244 at net/netfilter/core.c:218 __nf_hook_entries_try_shrink+0x49/0xcd
[..]

After allowing batching in nf_unregister_net_hooks its possible that an earlier
call to __nf_hook_entries_try_shrink already compacted the list.
If this happens we don't need to do anything.

Fixes: d3ad2c17b4 ("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:52 +02:00
Florian Westphal 8073e960a0 netfilter: nat: use keyed locks
no need to serialize on a single lock, we can partition the table and
add/delete in parallel to different slots.
This restores one of the advantages that got lost with the rhlist
revert.

Cc: Ivan Babrou <ibobrik@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:52 +02:00
Florian Westphal e1bf168774 netfilter: nat: Revert "netfilter: nat: convert nat bysrc hash to rhashtable"
This reverts commit 870190a9ec.

It was not a good idea. The custom hash table was a much better
fit for this purpose.

A fast lookup is not essential, in fact for most cases there is no lookup
at all because original tuple is not taken and can be used as-is.
What needs to be fast is insertion and deletion.

rhlist removal however requires a rhlist walk.
We can have thousands of entries in such a list if source port/addresses
are reused for multiple flows, if this happens removal requests are so
expensive that deletions of a few thousand flows can take several
seconds(!).

The advantages that we got from rhashtable are:
1) table auto-sizing
2) multiple locks

1) would be nice to have, but it is not essential as we have at
most one lookup per new flow, so even a million flows in the bysource
table are not a problem compared to current deletion cost.
2) is easy to add to custom hash table.

I tried to add hlist_node to rhlist to speed up rhltable_remove but this
isn't doable without changing semantics.  rhltable_remove_fast will
check that the to-be-deleted object is part of the table and that
requires a list walk that we want to avoid.

Furthermore, using hlist_node increases size of struct rhlist_head, which
in turn increases nf_conn size.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=196821
Reported-by: Ivan Babrou <ibobrik@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:50 +02:00