INFO: rcu detected stall in ip_rcv

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: d71f695c Linux 4.14.179
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=142d0a88100000
kernel config: https://syzkaller.appspot.com/x/.config?x=580f01c69a690433
dashboard link: https://syzkaller.appspot.com/bug?extid=9b014b43a8c134739409
compiler: gcc (GCC) 9.0.0 20181231 (experimental)

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

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+9b014b...@syzkaller.appspotmail.com

IPv6: sit1: Disabled Multicast RS
INFO: rcu_preempt self-detected stall on CPU
0-...: (1 GPs behind) idle=3e2/140000000000002/0 softirq=130184/130186 fqs=6
(t=10500 jiffies g=40401 c=40400 q=638)
rcu_preempt kthread starved for 10401 jiffies! g40401 c40400 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1
rcu_preempt R running task 29488 8 2 0x80000000
Call Trace:
schedule+0x8d/0x1b0 kernel/sched/core.c:3428
schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746
rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255
kthread+0x30d/0x420 kernel/kthread.c:232
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
NMI backtrace for cpu 0
CPU: 0 PID: 20150 Comm: syz-executor.3 Not tainted 4.14.179-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x13e/0x194 lib/dump_stack.c:58
nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62
trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline]
rcu_dump_cpu_stacks+0x16d/0x1b8 kernel/rcu/tree.c:1396
print_cpu_stall kernel/rcu/tree.c:1542 [inline]
check_cpu_stall kernel/rcu/tree.c:1610 [inline]
__rcu_pending kernel/rcu/tree.c:3390 [inline]
rcu_pending kernel/rcu/tree.c:3452 [inline]
rcu_check_callbacks.cold+0x490/0xdaa kernel/rcu/tree.c:2792
update_process_times+0x29/0x60 kernel/time/timer.c:1590
tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165
tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223
__run_hrtimer kernel/time/hrtimer.c:1223 [inline]
__hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287
hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
RIP: 0010:memset+0x0/0x40 mm/kasan/kasan.c:284
RSP: 0018:ffff8880aea07370 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000003 RBX: ffff888094a1d3c0 RCX: 00000000ffffffff
RDX: 0000000000000024 RSI: 0000000000000000 RDI: ffff8880a108cb40
RBP: ffff8880a108ca80 R08: ffffed1012943a91 R09: ffff888094a1d3c0
R10: ffffed1012943a90 R11: ffff888094a1d487 R12: 1ffff11015d40e70
R13: ffff8880a108cb40 R14: 0000000000000000 R15: 00000000000000c0
memset include/linux/string.h:332 [inline]
__alloc_skb+0x30a/0x4c0 net/core/skbuff.c:234
alloc_skb include/linux/skbuff.h:980 [inline]
_sctp_make_chunk+0x44/0x250 net/sctp/sm_make_chunk.c:1388
sctp_make_control+0x30/0x150 net/sctp/sm_make_chunk.c:1429
sctp_make_heartbeat_ack+0x32/0x100 net/sctp/sm_make_chunk.c:1178
sctp_sf_beat_8_3+0x3dc/0x620 net/sctp/sm_statefuns.c:1131
sctp_do_sm+0xf6/0x4a90 net/sctp/sm_sideeffect.c:1147
sctp_assoc_bh_rcv+0x2a2/0x5d0 net/sctp/associola.c:1096
sctp_inq_push+0x1be/0x250 net/sctp/inqueue.c:95
sctp_rcv+0x2336/0x2e30 net/sctp/input.c:267
ip_local_deliver_finish+0x245/0xaa0 net/ipv4/ip_input.c:216
NF_HOOK include/linux/netfilter.h:250 [inline]
NF_HOOK include/linux/netfilter.h:244 [inline]
ip_local_deliver+0x1a6/0x450 net/ipv4/ip_input.c:257
dst_input include/net/dst.h:468 [inline]
ip_rcv_finish+0x79b/0x1a10 net/ipv4/ip_input.c:396
NF_HOOK include/linux/netfilter.h:250 [inline]
NF_HOOK include/linux/netfilter.h:244 [inline]
ip_rcv+0x9d8/0xfec net/ipv4/ip_input.c:493
__netif_receive_skb_core+0x1e50/0x2c00 net/core/dev.c:4478
__netif_receive_skb+0x27/0x1a0 net/core/dev.c:4516
process_backlog+0x214/0x750 net/core/dev.c:5198
napi_poll net/core/dev.c:5599 [inline]
net_rx_action+0x456/0xe90 net/core/dev.c:5665
__do_softirq+0x254/0x9bf kernel/softirq.c:288
invoke_softirq kernel/softirq.c:368 [inline]
irq_exit+0x15b/0x1a0 kernel/softirq.c:409
exiting_irq arch/x86/include/asm/apic.h:648 [inline]
smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
</IRQ>
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x91/0xe0 kernel/locking/spinlock.c:192
RSP: 0018:ffff888049217548 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fa2cd1 RBX: 0000000000000286 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000286
RBP: ffffffff8a748d88 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880492175f8 R14: ffffffff8a748d88 R15: 0000000000000000
__debug_check_no_obj_freed lib/debugobjects.c:760 [inline]
debug_check_no_obj_freed+0x28e/0x6e4 lib/debugobjects.c:776
free_pages_prepare mm/page_alloc.c:1063 [inline]
free_pcp_prepare mm/page_alloc.c:1077 [inline]
free_hot_cold_page+0x222/0xca0 mm/page_alloc.c:2608
free_hot_cold_page_list+0x8f/0x310 mm/page_alloc.c:2656
release_pages+0x846/0xc00 mm/swap.c:820
tlb_flush_mmu_free+0x73/0x130 mm/memory.c:260
zap_pte_range mm/memory.c:1409 [inline]
zap_pmd_range mm/memory.c:1444 [inline]
zap_pud_range mm/memory.c:1473 [inline]
zap_p4d_range mm/memory.c:1494 [inline]
unmap_page_range+0x1308/0x1930 mm/memory.c:1515
unmap_single_vma+0x147/0x2b0 mm/memory.c:1560
unmap_vmas+0x9d/0x160 mm/memory.c:1590
exit_mmap+0x26d/0x4b0 mm/mmap.c:3056
__mmput kernel/fork.c:930 [inline]
mmput+0x103/0x420 kernel/fork.c:951
exit_mm kernel/exit.c:545 [inline]
do_exit+0x933/0x2b00 kernel/exit.c:845
do_group_exit+0x100/0x310 kernel/exit.c:955
get_signal+0x385/0x1ca0 kernel/signal.c:2423
do_signal+0x7c/0x1690 arch/x86/kernel/signal.c:814
exit_to_usermode_loop+0x159/0x220 arch/x86/entry/common.c:160
prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007fac23d88c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffff7 RBX: 00000000004ea260 RCX: 000000000045c829
RDX: 0000000020000100 RSI: 0000000040247007 RDI: ffffffffffffffff
RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 000000000000045a R14: 00000000004c70a1 R15: 00007fac23d896d4
IPv6: sit1: Disabled Multicast RS
IPv6: sit1: Disabled Multicast RS


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.