inconsistent lock state in xfrm_policy_lookup_inexact_addr

From: syzbot
Date: Wed Sep 16 2020 - 04:51:32 EST

Next message: syzbot: "possible deadlock in xfrm_policy_lookup_inexact_addr"
Previous message: Marc Zyngier: "Re: [PATCH 0/6] irqchip: Hybrid probing"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Hello,

syzbot found the following issue on:

HEAD commit: 6b02addb Add linux-next specific files for 20200915
git tree: linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=15888efd900000
kernel config: https://syzkaller.appspot.com/x/.config?x=7086d0e9e44d4a14
dashboard link: https://syzkaller.appspot.com/bug?extid=f4d0f0f7c860608404c4
compiler: gcc (GCC) 10.1.0-syz 20200507

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f4d0f0f7c860608404c4@xxxxxxxxxxxxxxxxxxxxxxxxx

================================
WARNING: inconsistent lock state
5.9.0-rc5-next-20200915-syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-R} usage.
kworker/1:1/23 [HC0[0]:SC1[1]:HE0:SE0] takes:
ffff8880a6ff5f28 (&s->seqcount#12){+.+-}-{0:0}, at: xfrm_policy_lookup_inexact_addr+0x57/0x200 net/xfrm/xfrm_policy.c:1909
{SOFTIRQ-ON-W} state was registered at:
lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398
write_seqcount_t_begin_nested include/linux/seqlock.h:509 [inline]
write_seqcount_t_begin include/linux/seqlock.h:535 [inline]
write_seqlock include/linux/seqlock.h:883 [inline]
xfrm_set_spdinfo+0x302/0x660 net/xfrm/xfrm_user.c:1185
xfrm_user_rcv_msg+0x414/0x700 net/xfrm/xfrm_user.c:2684
netlink_rcv_skb+0x15a/0x430 net/netlink/af_netlink.c:2470
xfrm_netlink_rcv+0x6b/0x90 net/xfrm/xfrm_user.c:2692
netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:671
____sys_sendmsg+0x6e8/0x810 net/socket.c:2362
___sys_sendmsg+0xf3/0x170 net/socket.c:2416
__sys_sendmsg+0xe5/0x1b0 net/socket.c:2449
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
irq event stamp: 2041637
hardirqs last enabled at (2041636): [<ffffffff86c293ab>] seqcount_lockdep_reader_access+0x14b/0x1a0 include/linux/seqlock.h:105
hardirqs last disabled at (2041637): [<ffffffff86c2937b>] seqcount_lockdep_reader_access+0x11b/0x1a0 include/linux/seqlock.h:102
softirqs last enabled at (2041616): [<ffffffff84b3745b>] wg_socket_send_skb_to_peer+0x14b/0x220 drivers/net/wireguard/socket.c:183
softirqs last disabled at (2041617): [<ffffffff88200f2f>] asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:786

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

CPU0
----
lock(&s->seqcount#12);
<Interrupt>
lock(&s->seqcount#12);

*** DEADLOCK ***

5 locks held by kworker/1:1/23:
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
#0: ffff88809dff9938 ((wq_completion)wg-crypt-wg0#5){+.+.}-{0:0}, at: process_one_work+0x821/0x15a0 kernel/workqueue.c:2240
#1: ffffc90000df7da8 ((work_completion)(&queue->work)){+.+.}-{0:0}, at: process_one_work+0x854/0x15a0 kernel/workqueue.c:2244
#2: ffffffff89e71c80 (rcu_read_lock){....}-{1:2}, at: __skb_unlink include/linux/skbuff.h:2067 [inline]
#2: ffffffff89e71c80 (rcu_read_lock){....}-{1:2}, at: __skb_dequeue include/linux/skbuff.h:2082 [inline]
#2: ffffffff89e71c80 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x270/0x8e0 net/core/dev.c:6284
#3: ffffffff89e71c80 (rcu_read_lock){....}-{1:2}, at: ip6_input_finish+0x0/0x160 net/ipv6/ip6_input.c:453
#4: ffffffff89e71c80 (rcu_read_lock){....}-{1:2}, at: xfrm_policy_lookup_bytype+0x104/0xa40 net/xfrm/xfrm_policy.c:2082

stack backtrace:
CPU: 1 PID: 23 Comm: kworker/1:1 Not tainted 5.9.0-rc5-next-20200915-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: wg-crypt-wg0 wg_packet_tx_worker
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x198/0x1fb lib/dump_stack.c:118
print_usage_bug kernel/locking/lockdep.c:3694 [inline]
valid_state kernel/locking/lockdep.c:3705 [inline]
mark_lock_irq kernel/locking/lockdep.c:3908 [inline]
mark_lock.cold+0x13/0x10d kernel/locking/lockdep.c:4375
mark_usage kernel/locking/lockdep.c:4252 [inline]
__lock_acquire+0x1402/0x55d0 kernel/locking/lockdep.c:4750
lock_acquire+0x1f2/0xaa0 kernel/locking/lockdep.c:5398
seqcount_lockdep_reader_access+0x139/0x1a0 include/linux/seqlock.h:103
xfrm_policy_lookup_inexact_addr+0x57/0x200 net/xfrm/xfrm_policy.c:1909
xfrm_policy_find_inexact_candidates+0xac/0x1d0 net/xfrm/xfrm_policy.c:1953
xfrm_policy_lookup_bytype+0x4b8/0xa40 net/xfrm/xfrm_policy.c:2108
xfrm_policy_lookup net/xfrm/xfrm_policy.c:2144 [inline]
__xfrm_policy_check+0x110e/0x2650 net/xfrm/xfrm_policy.c:3572
__xfrm_policy_check2 include/net/xfrm.h:1097 [inline]
xfrm_policy_check include/net/xfrm.h:1106 [inline]
xfrm6_policy_check include/net/xfrm.h:1116 [inline]
udpv6_queue_rcv_one_skb+0x570/0x15c0 net/ipv6/udp.c:660
udpv6_queue_rcv_skb net/ipv6/udp.c:744 [inline]
udp6_unicast_rcv_skb+0x259/0x490 net/ipv6/udp.c:886
__udp6_lib_rcv+0xb35/0x2750 net/ipv6/udp.c:970
ip6_protocol_deliver_rcu+0x2e8/0x1660 net/ipv6/ip6_input.c:433
ip6_input_finish+0x7f/0x160 net/ipv6/ip6_input.c:474
NF_HOOK include/linux/netfilter.h:301 [inline]
NF_HOOK include/linux/netfilter.h:295 [inline]
ip6_input+0x9c/0xd0 net/ipv6/ip6_input.c:483
dst_input include/net/dst.h:449 [inline]
ip6_rcv_finish net/ipv6/ip6_input.c:76 [inline]
NF_HOOK include/linux/netfilter.h:301 [inline]
NF_HOOK include/linux/netfilter.h:295 [inline]
ipv6_rcv+0x28e/0x3c0 net/ipv6/ip6_input.c:307
__netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5287
__netif_receive_skb+0x27/0x1c0 net/core/dev.c:5401
process_backlog+0x2e1/0x8e0 net/core/dev.c:6286
napi_poll net/core/dev.c:6730 [inline]
net_rx_action+0x572/0x1300 net/core/dev.c:6800
__do_softirq+0x202/0xa42 kernel/softirq.c:298
asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:786
</IRQ>
__run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
do_softirq_own_stack+0x9d/0xd0 arch/x86/kernel/irq_64.c:77
do_softirq kernel/softirq.c:343 [inline]
do_softirq+0x154/0x1b0 kernel/softirq.c:330
__local_bh_enable_ip+0x196/0x1f0 kernel/softirq.c:195
wg_socket_send_skb_to_peer+0x14b/0x220 drivers/net/wireguard/socket.c:183
wg_packet_create_data_done drivers/net/wireguard/send.c:252 [inline]
wg_packet_tx_worker+0x2f9/0x980 drivers/net/wireguard/send.c:280
process_one_work+0x933/0x15a0 kernel/workqueue.c:2269
worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
kthread+0x3af/0x4a0 kernel/kthread.c:292
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

Next message: syzbot: "possible deadlock in xfrm_policy_lookup_inexact_addr"
Previous message: Marc Zyngier: "Re: [PATCH 0/6] irqchip: Hybrid probing"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]