linux-stable.git/net/netfilter/ipvs, branch v4.17.3

ipvs: fix buffer overflow with sync daemon and service

2018-05-23T09:24:11+00:00

syzkaller reports for buffer overflow for interface name
when starting sync daemons [1]

What we do is that we copy user structure into larger stack
buffer but later we search NUL past the stack buffer.
The same happens for sched_name when adding/editing virtual server.

We are restricted by IP_VS_SCHEDNAME_MAXLEN and IP_VS_IFNAME_MAXLEN
being used as size in include/uapi/linux/ip_vs.h, so they
include the space for NUL.

As using strlcpy is wrong for unsafe source, replace it with
strscpy and add checks to return EINVAL if source string is not
NUL-terminated. The incomplete strlcpy fix comes from 2.6.13.

For the netlink interface reduce the len parameter for
IPVS_DAEMON_ATTR_MCAST_IFN and IPVS_SVC_ATTR_SCHED_NAME,
so that we get proper EINVAL.

[1]
kernel BUG at lib/string.c:1052!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
    (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 373 Comm: syz-executor936 Not tainted 4.17.0-rc4+ #45
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:fortify_panic+0x13/0x20 lib/string.c:1051
RSP: 0018:ffff8801c976f800 EFLAGS: 00010282
RAX: 0000000000000022 RBX: 0000000000000040 RCX: 0000000000000000
RDX: 0000000000000022 RSI: ffffffff8160f6f1 RDI: ffffed00392edef6
RBP: ffff8801c976f800 R08: ffff8801cf4c62c0 R09: ffffed003b5e4fb0
R10: ffffed003b5e4fb0 R11: ffff8801daf27d87 R12: ffff8801c976fa20
R13: ffff8801c976fae4 R14: ffff8801c976fae0 R15: 000000000000048b
FS:  00007fd99f75e700(0000) GS:ffff8801daf00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200001c0 CR3: 00000001d6843000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  strlen include/linux/string.h:270 [inline]
  strlcpy include/linux/string.h:293 [inline]
  do_ip_vs_set_ctl+0x31c/0x1d00 net/netfilter/ipvs/ip_vs_ctl.c:2388
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x7d/0xd0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0xd8/0xf0 net/ipv4/ip_sockglue.c:1253
  udp_setsockopt+0x62/0xa0 net/ipv4/udp.c:2487
  ipv6_setsockopt+0x149/0x170 net/ipv6/ipv6_sockglue.c:917
  tcp_setsockopt+0x93/0xe0 net/ipv4/tcp.c:3057
  sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:3046
  __sys_setsockopt+0x1bd/0x390 net/socket.c:1903
  __do_sys_setsockopt net/socket.c:1914 [inline]
  __se_sys_setsockopt net/socket.c:1911 [inline]
  __x64_sys_setsockopt+0xbe/0x150 net/socket.c:1911
  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447369
RSP: 002b:00007fd99f75dda8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000006e39e4 RCX: 0000000000447369
RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000018 R09: 0000000000000000
R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000006e39e0
R13: 75a1ff93f0896195 R14: 6f745f3168746576 R15: 0000000000000001
Code: 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 0b 48 89 df e8 d2 8f 48 fa eb
de 55 48 89 fe 48 c7 c7 60 65 64 88 48 89 e5 e8 91 dd f3 f9 <0f> 0b 90 90
90 90 90 90 90 90 90 90 90 55 48 89 e5 41 57 41 56
RIP: fortify_panic+0x13/0x20 lib/string.c:1051 RSP: ffff8801c976f800

Reported-and-tested-by: syzbot+aac887f77319868646df@syzkaller.appspotmail.com
Fixes: e4ff67513096 ("ipvs: add sync_maxlen parameter for the sync daemon")
Fixes: 4da62fc70d7c ("[IPVS]: Fix for overflows")
Signed-off-by: Julian Anastasov 
Acked-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso

ipvs: fix stats update from local clients

2018-05-08T12:15:21+00:00

Local clients are not properly synchronized on 32-bit CPUs when
updating stats (3.10+). Now it is possible estimation_timer (timer),
a stats reader, to interrupt the local client in the middle of
write_seqcount_{begin,end} sequence leading to loop (DEADLOCK).
The same interrupt can happen from received packet (SoftIRQ)
which updates the same per-CPU stats.

Fix it by disabling BH while updating stats.

Found with debug:

WARNING: inconsistent lock state
4.17.0-rc2-00105-g35cb6d7-dirty #2 Not tainted
--------------------------------
inconsistent {IN-SOFTIRQ-R} -> {SOFTIRQ-ON-W} usage.
ftp/2545 [HC0[0]:SC0[0]:HE1:SE1] takes:
86845479 (&syncp->seq#6){+.+-}, at: ip_vs_schedule+0x1c5/0x59e [ip_vs]
{IN-SOFTIRQ-R} state was registered at:
 lock_acquire+0x44/0x5b
 estimation_timer+0x1b3/0x341 [ip_vs]
 call_timer_fn+0x54/0xcd
 run_timer_softirq+0x10c/0x12b
 __do_softirq+0xc1/0x1a9
 do_softirq_own_stack+0x1d/0x23
 irq_exit+0x4a/0x64
 smp_apic_timer_interrupt+0x63/0x71
 apic_timer_interrupt+0x3a/0x40
 default_idle+0xa/0xc
 arch_cpu_idle+0x9/0xb
 default_idle_call+0x21/0x23
 do_idle+0xa0/0x167
 cpu_startup_entry+0x19/0x1b
 start_secondary+0x133/0x182
 startup_32_smp+0x164/0x168
irq event stamp: 42213

other info that might help us debug this:
Possible unsafe locking scenario:

      CPU0
      ----
 lock(&syncp->seq#6);
 
   lock(&syncp->seq#6);

*** DEADLOCK ***

Fixes: ac69269a45e8 ("ipvs: do not disable bh for long time")
Signed-off-by: Julian Anastasov 
Acked-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso

ipvs: fix refcount usage for conns in ops mode

2018-05-08T12:15:12+00:00

Connections in One-packet scheduling mode (-o, --ops) are
removed with refcnt=0 because they are not hashed in conn table.
To avoid refcount_dec reporting this as error, change them to be
removed with refcount_dec_if_one as all other connections.

refcount_t hit zero at ip_vs_conn_put+0x31/0x40 [ip_vs]
in sh[15519], uid/euid: 497/497
WARNING: CPU: 0 PID: 15519 at ../kernel/panic.c:657
refcount_error_report+0x94/0x9e
Modules linked in: ip_vs_rr cirrus ttm sb_edac
edac_core drm_kms_helper crct10dif_pclmul crc32_pclmul
ghash_clmulni_intel pcbc mousedev drm aesni_intel aes_x86_64
crypto_simd glue_helper cryptd psmouse evdev input_leds led_class
intel_agp fb_sys_fops syscopyarea sysfillrect intel_rapl_perf mac_hid
intel_gtt serio_raw sysimgblt agpgart i2c_piix4 i2c_core ata_generic
pata_acpi floppy cfg80211 rfkill button loop macvlan ip_vs
nf_conntrack libcrc32c crc32c_generic ip_tables x_tables ipv6
crc_ccitt autofs4 ext4 crc16 mbcache jbd2 fscrypto ata_piix libata
atkbd libps2 scsi_mod crc32c_intel i8042 rtc_cmos serio af_packet
dm_mod dax fuse xen_netfront xen_blkfront
CPU: 0 PID: 15519 Comm: sh Tainted: G        W
4.15.17 #1-NixOS
Hardware name: Xen HVM domU, BIOS 4.2.amazon 08/24/2006
RIP: 0010:refcount_error_report+0x94/0x9e
RSP: 0000:ffffa344dde039c8 EFLAGS: 00010296
RAX: 0000000000000057 RBX: ffffffff92f20e06 RCX: 0000000000000006
RDX: 0000000000000007 RSI: 0000000000000086 RDI: ffffa344dde165c0
RBP: ffffa344dde03b08 R08: 0000000000000218 R09: 0000000000000004
R10: ffffffff93006a80 R11: 0000000000000001 R12: ffffa344d68cd100
R13: 00000000000001f1 R14: ffffffff92f12fb0 R15: 0000000000000004
FS:  00007fc9d2040fc0(0000) GS:ffffa344dde00000(0000)
knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000000262a000 CR3: 0000000016a0c004 CR4: 00000000001606f0
Call Trace:
 
 ex_handler_refcount+0x4e/0x80
 fixup_exception+0x33/0x40
 do_trap+0x83/0x140
 do_error_trap+0x83/0xf0
 ? ip_vs_conn_drop_conntrack+0x120/0x1a5 [ip_vs]
 ? ip_finish_output2+0x29c/0x390
 ? ip_finish_output2+0x1a2/0x390
 invalid_op+0x1b/0x40
RIP: 0010:ip_vs_conn_put+0x31/0x40 [ip_vs]
RSP: 0000:ffffa344dde03bb8 EFLAGS: 00010246
RAX: 0000000000000001 RBX: ffffa344df31cf00 RCX: ffffa344d7450198
RDX: 0000000000000003 RSI: 00000000fffffe01 RDI: ffffa344d7450140
RBP: 0000000000000002 R08: 0000000000000476 R09: 0000000000000000
R10: ffffa344dde03b28 R11: ffffa344df200000 R12: ffffa344d7d09000
R13: ffffa344def3a980 R14: ffffffffc04f6e20 R15: 0000000000000008
 ip_vs_in.part.29.constprop.36+0x34f/0x640 [ip_vs]
 ? ip_vs_conn_out_get+0xe0/0xe0 [ip_vs]
 ip_vs_remote_request4+0x47/0xa0 [ip_vs]
 ? ip_vs_in.part.29.constprop.36+0x640/0x640 [ip_vs]
 nf_hook_slow+0x43/0xc0
 ip_local_deliver+0xac/0xc0
 ? ip_rcv_finish+0x400/0x400
 ip_rcv+0x26c/0x380
 __netif_receive_skb_core+0x3a0/0xb10
 ? inet_gro_receive+0x23c/0x2b0
 ? netif_receive_skb_internal+0x24/0xb0
 netif_receive_skb_internal+0x24/0xb0
 napi_gro_receive+0xb8/0xe0
 xennet_poll+0x676/0xb40 [xen_netfront]
 net_rx_action+0x139/0x3a0
 __do_softirq+0xde/0x2b4
 irq_exit+0xae/0xb0
 xen_evtchn_do_upcall+0x2c/0x40
 xen_hvm_callback_vector+0x7d/0x90
 
RIP: 0033:0x7fc9d11c91f9
RSP: 002b:00007ffebe8a2ea0 EFLAGS: 00000202 ORIG_RAX:
ffffffffffffff0c
RAX: 00000000ffffffff RBX: 0000000002609808 RCX: 0000000000000054
RDX: 0000000000000001 RSI: 0000000002605440 RDI: 00000000025f940e
RBP: 00000000025f940e R08: 000000000260213d R09: 1999999999999999
R10: 000000000262a808 R11: 00000000025f942d R12: 00000000025f940e
R13: 00007fc9d1301e20 R14: 00000000025f9408 R15: 00007fc9d1302720
Code: 48 8b 95 80 00 00 00 41 55 49 8d 8c 24 e0 05 00
00 45 8b 84 24 38 04 00 00 41 89 c1 48 89 de 48 c7 c7 a8 2f f2 92 e8
7c fa ff ff <0f> 0b 58 5b 5d 41 5c 41 5d c3 0f 1f 44 00 00 55 48 89 e5
41 56

Reported-by: Net Filter 
Fixes: b54ab92b84b6 ("netfilter: refcounter conversions")
Signed-off-by: Julian Anastasov 
Acked-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso

ipvs: fix rtnl_lock lockups caused by start_sync_thread

2018-04-09T15:05:27+00:00

syzkaller reports for wrong rtnl_lock usage in sync code [1] and [2]

We have 2 problems in start_sync_thread if error path is
taken, eg. on memory allocation error or failure to configure
sockets for mcast group or addr/port binding:

1. recursive locking: holding rtnl_lock while calling sock_release
which in turn calls again rtnl_lock in ip_mc_drop_socket to leave
the mcast group, as noticed by Florian Westphal. Additionally,
sock_release can not be called while holding sync_mutex (ABBA
deadlock).

2. task hung: holding rtnl_lock while calling kthread_stop to
stop the running kthreads. As the kthreads do the same to leave
the mcast group (sock_release -> ip_mc_drop_socket -> rtnl_lock)
they hang.

Fix the problems by calling rtnl_unlock early in the error path,
now sock_release is called after unlocking both mutexes.

Problem 3 (task hung reported by syzkaller [2]) is variant of
problem 2: use _trylock to prevent one user to call rtnl_lock and
then while waiting for sync_mutex to block kthreads that execute
sock_release when they are stopped by stop_sync_thread.

[1]
IPVS: stopping backup sync thread 4500 ...
WARNING: possible recursive locking detected
4.16.0-rc7+ #3 Not tainted
--------------------------------------------
syzkaller688027/4497 is trying to acquire lock:
  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

but task is already holding lock:
IPVS: stopping backup sync thread 4495 ...
  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(rtnl_mutex);
   lock(rtnl_mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

2 locks held by syzkaller688027/4497:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000bb14d7fb>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
  #1:  (ipvs->sync_mutex){+.+.}, at: [<00000000703f78e3>]
do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388

stack backtrace:
CPU: 1 PID: 4497 Comm: syzkaller688027 Not tainted 4.16.0-rc7+ #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x194/0x24d lib/dump_stack.c:53
  print_deadlock_bug kernel/locking/lockdep.c:1761 [inline]
  check_deadlock kernel/locking/lockdep.c:1805 [inline]
  validate_chain kernel/locking/lockdep.c:2401 [inline]
  __lock_acquire+0xe8f/0x3e00 kernel/locking/lockdep.c:3431
  lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:3920
  __mutex_lock_common kernel/locking/mutex.c:756 [inline]
  __mutex_lock+0x16f/0x1a80 kernel/locking/mutex.c:893
  mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:908
  rtnl_lock+0x17/0x20 net/core/rtnetlink.c:74
  ip_mc_drop_socket+0x88/0x230 net/ipv4/igmp.c:2643
  inet_release+0x4e/0x1c0 net/ipv4/af_inet.c:413
  sock_release+0x8d/0x1e0 net/socket.c:595
  start_sync_thread+0x2213/0x2b70 net/netfilter/ipvs/ip_vs_sync.c:1924
  do_ip_vs_set_ctl+0x1139/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2389
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1261
  udp_setsockopt+0x45/0x80 net/ipv4/udp.c:2406
  sock_common_setsockopt+0x95/0xd0 net/core/sock.c:2975
  SYSC_setsockopt net/socket.c:1849 [inline]
  SyS_setsockopt+0x189/0x360 net/socket.c:1828
  do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x446a69
RSP: 002b:00007fa1c3a64da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000446a69
RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006e29fc R08: 0000000000000018 R09: 0000000000000000
R10: 00000000200000c0 R11: 0000000000000246 R12: 00000000006e29f8
R13: 00676e697279656b R14: 00007fa1c3a659c0 R15: 00000000006e2b60

[2]
IPVS: sync thread started: state = BACKUP, mcast_ifn = syz_tun, syncid = 4,
id = 0
IPVS: stopping backup sync thread 25415 ...
INFO: task syz-executor7:25421 blocked for more than 120 seconds.
       Not tainted 4.16.0-rc6+ #284
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor7   D23688 25421   4408 0x00000004
Call Trace:
  context_switch kernel/sched/core.c:2862 [inline]
  __schedule+0x8fb/0x1ec0 kernel/sched/core.c:3440
  schedule+0xf5/0x430 kernel/sched/core.c:3499
  schedule_timeout+0x1a3/0x230 kernel/time/timer.c:1777
  do_wait_for_common kernel/sched/completion.c:86 [inline]
  __wait_for_common kernel/sched/completion.c:107 [inline]
  wait_for_common kernel/sched/completion.c:118 [inline]
  wait_for_completion+0x415/0x770 kernel/sched/completion.c:139
  kthread_stop+0x14a/0x7a0 kernel/kthread.c:530
  stop_sync_thread+0x3d9/0x740 net/netfilter/ipvs/ip_vs_sync.c:1996
  do_ip_vs_set_ctl+0x2b1/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2394
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x67/0xc0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x97/0xa0 net/ipv4/ip_sockglue.c:1253
  sctp_setsockopt+0x2ca/0x63e0 net/sctp/socket.c:4154
  sock_common_setsockopt+0x95/0xd0 net/core/sock.c:3039
  SYSC_setsockopt net/socket.c:1850 [inline]
  SyS_setsockopt+0x189/0x360 net/socket.c:1829
  do_syscall_64+0x281/0x940 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x454889
RSP: 002b:00007fc927626c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fc9276276d4 RCX: 0000000000454889
RDX: 000000000000048c RSI: 0000000000000000 RDI: 0000000000000017
RBP: 000000000072bf58 R08: 0000000000000018 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000051c R14: 00000000006f9b40 R15: 0000000000000001

Showing all locks held in the system:
2 locks held by khungtaskd/868:
  #0:  (rcu_read_lock){....}, at: [<00000000a1a8f002>]
check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline]
  #0:  (rcu_read_lock){....}, at: [<00000000a1a8f002>] watchdog+0x1c5/0xd60
kernel/hung_task.c:249
  #1:  (tasklist_lock){.+.+}, at: [<0000000037c2f8f9>]
debug_show_all_locks+0xd3/0x3d0 kernel/locking/lockdep.c:4470
1 lock held by rsyslogd/4247:
  #0:  (&f->f_pos_lock){+.+.}, at: [<000000000d8d6983>]
__fdget_pos+0x12b/0x190 fs/file.c:765
2 locks held by getty/4338:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4339:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4340:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4341:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4342:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4343:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
2 locks held by getty/4344:
  #0:  (&tty->ldisc_sem){++++}, at: [<00000000bee98654>]
ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365
  #1:  (&ldata->atomic_read_lock){+.+.}, at: [<00000000c1d180aa>]
n_tty_read+0x2ef/0x1a40 drivers/tty/n_tty.c:2131
3 locks held by kworker/0:5/6494:
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] work_static include/linux/workqueue.h:198 [inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] set_work_data kernel/workqueue.c:619 [inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] set_work_pool_and_clear_pending kernel/workqueue.c:646
[inline]
  #0:  ((wq_completion)"%s"("ipv6_addrconf")){+.+.}, at:
[<00000000a062b18e>] process_one_work+0xb12/0x1bb0 kernel/workqueue.c:2084
  #1:  ((addr_chk_work).work){+.+.}, at: [<00000000278427d5>]
process_one_work+0xb89/0x1bb0 kernel/workqueue.c:2088
  #2:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
1 lock held by syz-executor7/25421:
  #0:  (ipvs->sync_mutex){+.+.}, at: [<00000000d414a689>]
do_ip_vs_set_ctl+0x277/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2393
2 locks held by syz-executor7/25427:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
  #1:  (ipvs->sync_mutex){+.+.}, at: [<00000000e6d48489>]
do_ip_vs_set_ctl+0x10f8/0x1cc0 net/netfilter/ipvs/ip_vs_ctl.c:2388
1 lock held by syz-executor7/25435:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74
1 lock held by ipvs-b:2:0/25415:
  #0:  (rtnl_mutex){+.+.}, at: [<00000000066e35ac>] rtnl_lock+0x17/0x20
net/core/rtnetlink.c:74

Reported-and-tested-by: syzbot+a46d6abf9d56b1365a72@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+5fe074c01b2032ce9618@syzkaller.appspotmail.com
Fixes: e0b26cc997d5 ("ipvs: call rtnl_lock early")
Signed-off-by: Julian Anastasov 
Signed-off-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso

Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next

2018-03-30T15:41:18+00:00

Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter/IPVS updates for your net-next
tree. This batch comes with more input sanitization for xtables to
address bug reports from fuzzers, preparation works to the flowtable
infrastructure and assorted updates. In no particular order, they are:

1) Make sure userspace provides a valid standard target verdict, from
   Florian Westphal.

2) Sanitize error target size, also from Florian.

3) Validate that last rule in basechain matches underflow/policy since
   userspace assumes this when decoding the ruleset blob that comes
   from the kernel, from Florian.

4) Consolidate hook entry checks through xt_check_table_hooks(),
   patch from Florian.

5) Cap ruleset allocations at 512 mbytes, 134217728 rules and reject
   very large compat offset arrays, so we have a reasonable upper limit
   and fuzzers don't exercise the oom-killer. Patches from Florian.

6) Several WARN_ON checks on xtables mutex helper, from Florian.

7) xt_rateest now has a hashtable per net, from Cong Wang.

8) Consolidate counter allocation in xt_counters_alloc(), from Florian.

9) Earlier xt_table_unlock() call in {ip,ip6,arp,eb}tables, patch
   from Xin Long.

10) Set FLOW_OFFLOAD_DIR_* to IP_CT_DIR_* definitions, patch from
    Felix Fietkau.

11) Consolidate code through flow_offload_fill_dir(), also from Felix.

12) Inline ip6_dst_mtu_forward() just like ip_dst_mtu_maybe_forward()
    to remove a dependency with flowtable and ipv6.ko, from Felix.

13) Cache mtu size in flow_offload_tuple object, this is safe for
    forwarding as f87c10a8aa1e describes, from Felix.

14) Rename nf_flow_table.c to nf_flow_table_core.o, to simplify too
    modular infrastructure, from Felix.

15) Add rt0, rt2 and rt4 IPv6 routing extension support, patch from
    Ahmed Abdelsalam.

16) Remove unused parameter in nf_conncount_count(), from Yi-Hung Wei.

17) Support for counting only to nf_conncount infrastructure, patch
    from Yi-Hung Wei.

18) Add strict NFT_CT_{SRC_IP,DST_IP,SRC_IP6,DST_IP6} key datatypes
    to nft_ct.

19) Use boolean as return value from ipt_ah and from IPVS too, patch
    from Gustavo A. R. Silva.

20) Remove useless parameters in nfnl_acct_overquota() and
    nf_conntrack_broadcast_help(), from Taehee Yoo.

21) Use ipv6_addr_is_multicast() from xt_cluster, also from Taehee Yoo.

22) Statify nf_tables_obj_lookup_byhandle, patch from Fengguang Wu.

23) Fix typo in xt_limit, from Geert Uytterhoeven.

24) Do no use VLAs in Netfilter code, again from Gustavo.

25) Use ADD_COUNTER from ebtables, from Taehee Yoo.

26) Bitshift support for CONNMARK and MARK targets, from Jack Ma.

27) Use pr_*() and add pr_fmt(), from Arushi Singhal.

28) Add synproxy support to ctnetlink.

29) ICMP type and IGMP matching support for ebtables, patches from
    Matthias Schiffer.

30) Support for the revision infrastructure to ebtables, from
    Bernie Harris.

31) String match support for ebtables, also from Bernie.

32) Documentation for the new flowtable infrastructure.

33) Use generic comparison functions in ebt_stp, from Joe Perches.

34) Demodularize filter chains in nftables.

35) Register conntrack hooks in case nftables NAT chain is added.

36) Merge assignments with return in a couple of spots in the
    Netfilter codebase, also from Arushi.

37) Document that xtables percpu counters are stored in the same
    memory area, from Ben Hutchings.

38) Revert mark_source_chains() sanity checks that break existing
    rulesets, from Florian Westphal.

39) Use is_zero_ether_addr() in the ipset codebase, from Joe Perches.
====================

Signed-off-by: David S. Miller

net: Drop pernet_operations::async

2018-03-27T17:18:09+00:00

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai 
Signed-off-by: David S. Miller

net: Convert ip_vs_ftp_ops

2018-03-17T21:07:39+00:00

These pernet_operations register and unregister ipvs app.
register_ip_vs_app(), unregister_ip_vs_app() and
register_ip_vs_app_inc() modify per-net structures,
and there are no global structures touched. So,
this looks safe to be marked as async.

Signed-off-by: Kirill Tkhai 
Signed-off-by: David S. Miller

net: Convert ipvs_core_dev_ops

2018-03-17T21:07:39+00:00

Exit method stops two per-net threads and cancels
delayed work. Everything looks nicely per-net divided.

Signed-off-by: Kirill Tkhai 
Signed-off-by: David S. Miller

net: Convert ipvs_core_ops

2018-03-17T21:07:39+00:00

These pernet_operations register and unregister nf hooks,
/proc entries, sysctl, percpu statistics. There are several
global lists, and the only list modified without exclusive
locks is ip_vs_conn_tab in ip_vs_conn_flush(). We iterate
the list and force the timers expire at the moment. Since
there were possible several timer expirations before this
patch, and since they are safe, the patch does not invent
new parallelism of their destruction. These pernet_operations
look safe to be converted.

Signed-off-by: Kirill Tkhai 
Signed-off-by: David S. Miller

ipvs: use true and false for boolean values

2018-03-13T16:30:29+00:00

Assign true or false to boolean variables instead of an integer value.

This issue was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva 
Signed-off-by: Simon Horman 
Signed-off-by: Pablo Neira Ayuso