INFO: rcu detected stall in sctp_generate_heartbeat_event (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 54ecb8f7 Linux 5.4-rc1
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1406f339600000
kernel config: https://syzkaller.appspot.com/x/.config?x=fb0b431ccdf08c1c
dashboard link: https://syzkaller.appspot.com/bug?extid=c3fa9849e3ce792ea318
compiler: clang version 9.0.0 (/home/glider/llvm/clang
80fee25776c2fb61e74c1ecb1a523375c2500b69)
CC: [da...@davemloft.net d...@cumulusnetworks.com
linux-...@vger.kernel.org net...@vger.kernel.org]

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+c3fa98...@syzkaller.appspotmail.com

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 0-....: (10500 ticks this GP) idle=74a/1/0x4000000000000004
softirq=471229/471229 fqs=285
(t=10500 jiffies g=556597 q=2355)
NMI backtrace for cpu 0
CPU: 0 PID: 15632 Comm: syz-executor.1 Not tainted 5.4.0-rc1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
<IRQ>
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
rcu_pending kernel/rcu/tree.c:2795 [inline]
rcu_sched_clock_irq+0xe22/0x1ae0 kernel/rcu/tree.c:2244
update_process_times+0x12d/0x180 kernel/time/timer.c:1726
tick_sched_handle kernel/time/tick-sched.c:167 [inline]
tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1299
__run_hrtimer kernel/time/hrtimer.c:1514 [inline]
__hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1576
hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1638
local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
RIP: 0010:__read_once_size include/linux/compiler.h:199 [inline]
RIP: 0010:dev_get_by_index_rcu+0x60/0x140 net/core/dev.c:838
Code: 08 4c 89 ff e8 51 36 da fb 41 0f b6 de 48 c1 e3 03 49 03 1f 48 89 d8
48 c1 e8 03 42 80 3c 28 00 74 08 48 89 df e8 30 36 da fb <4c> 8b 23 31 ff
4c 89 e6 e8 b3 01 a1 fb 4d 85 e4 74 09 49 81 c4 38
RSP: 0018:ffff8880aea09390 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff11011308061 RBX: ffff888089840308 RCX: ffff8880975a0440
RDX: 0000000000000101 RSI: 0000000000000001 RDI: ffff8880a0cdc3c0
RBP: ffff8880aea093b8 R08: ffffffff87674ff9 R09: ffffed1015d46b05
R10: ffffed1015d46b05 R11: 0000000000000000 R12: ffff88807effdb34
R13: dffffc0000000000 R14: 0000000000000001 R15: ffff8880a0cdc588
l3mdev_update_flow+0x227/0x4c0 net/l3mdev/l3mdev.c:203
fib6_rule_lookup+0x140/0x640 net/ipv6/fib6_rules.c:103
ip6_route_output_flags_noref+0x2a6/0x350 net/ipv6/route.c:2484
ip6_route_output_flags+0xbd/0x4f0 net/ipv6/route.c:2497
ip6_route_output include/net/ip6_route.h:98 [inline]
ip6_dst_lookup_tail+0x255/0x1230 net/ipv6/ip6_output.c:1022
ip6_dst_lookup_flow+0x8c/0x160 net/ipv6/ip6_output.c:1150
sctp_v6_get_dst+0x60b/0x1710 net/sctp/ipv6.c:278
sctp_transport_route+0x10b/0x2b0 net/sctp/transport.c:297
sctp_packet_config+0x488/0xc90 net/sctp/output.c:103
sctp_outq_select_transport+0x4ac/0x5c0 net/sctp/outqueue.c:858
sctp_outq_flush_ctrl net/sctp/outqueue.c:892 [inline]
sctp_outq_flush+0x3b5/0x31d0 net/sctp/outqueue.c:1185
sctp_outq_uncork+0x77/0xb0 net/sctp/outqueue.c:757
sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1781 [inline]
sctp_side_effects net/sctp/sm_sideeffect.c:1184 [inline]
sctp_do_sm+0x53a6/0x5720 net/sctp/sm_sideeffect.c:1155
sctp_generate_heartbeat_event+0x2f6/0x400 net/sctp/sm_sideeffect.c:391
call_timer_fn+0x95/0x170 kernel/time/timer.c:1404
expire_timers kernel/time/timer.c:1449 [inline]
__run_timers+0x7b6/0x990 kernel/time/timer.c:1773
run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1786
__do_softirq+0x333/0x7c4 arch/x86/include/asm/paravirt.h:766
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0x227/0x230 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:536 [inline]
smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1137
apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
</IRQ>
RIP: 0010:tomoyo_domain_quota_is_ok+0xd2/0x580 security/tomoyo/util.c:1035
Code: d4 00 00 00 00 eb 06 90 e8 5b 4e 67 fe 4d 89 e6 4d 8d 7c 24 18 4c 89
f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 <84> c0 0f 85 5d
02 00 00 41 0f b6 1f 31 ff 89 de e8 a9 50 67 fe 85
RSP: 0018:ffff88820e5df6e0 EFLAGS: 00000a06 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000000 RBX: ffff88809698859a RCX: dffffc0000000000
RDX: ffffc9000804c000 RSI: 0000000000038cab RDI: 0000000000038cac
RBP: ffff88820e5df720 R08: 0000000000000001 R09: ffffffff830bd785
R10: ffff8880975a0440 R11: 0000000000000007 R12: ffff888099b55980
R13: ffff888083041d10 R14: ffff888099b55980 R15: ffff888099b55998
tomoyo_supervisor+0x274/0x1330 security/tomoyo/common.c:2087
tomoyo_audit_path_log security/tomoyo/file.c:168 [inline]
tomoyo_path_permission security/tomoyo/file.c:587 [inline]
tomoyo_check_open_permission+0x454/0x9d0 security/tomoyo/file.c:777
tomoyo_file_open+0x141/0x190 security/tomoyo/tomoyo.c:319
security_file_open+0x65/0x2f0 security/security.c:1497
do_dentry_open+0x345/0xf80 fs/open.c:784
vfs_open+0x73/0x80 fs/open.c:914
do_last fs/namei.c:3408 [inline]
path_openat+0x1397/0x4420 fs/namei.c:3525
do_filp_open+0x192/0x3d0 fs/namei.c:3555
do_sys_open+0x29f/0x560 fs/open.c:1097
__do_sys_openat fs/open.c:1124 [inline]
__se_sys_openat fs/open.c:1118 [inline]
__x64_sys_openat+0xa2/0xb0 fs/open.c:1118
do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x459a29
Code: fd b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7
48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff
ff 0f 83 cb b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f77ac32fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000459a29
RDX: 0000000000000000 RSI: 0000000020000240 RDI: ffffffffffffff9c
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f77ac3306d4
R13: 00000000004c6595 R14: 00000000004db8c0 R15: 00000000ffffffff


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[syzbot]

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