syzbot


BUG: soft lockup in ipv6_rcv

Status: upstream: reported C repro on 2021/04/08 17:19
Reported-by: syzbot+449ba0cd75eafedbce50@syzkaller.appspotmail.com
First crash: 669d, last: 191d

Fix bisection: failed (bisect log)
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream BUG: soft lockup in ipv6_rcv 24 1281d 1286d 0/24 auto-closed as invalid on 2019/10/25 14:11
upstream INFO: rcu detected stall in ipv6_rcv (2) C done 550 287d 1291d 0/24 upstream: reported C repro on 2019/07/26 09:38
upstream INFO: rcu detected stall in ipv6_rcv 7 1471d 1508d 12/24 fixed on 2019/03/06 07:43
linux-4.19 INFO: rcu detected stall in ipv6_rcv 1 806d 806d 0/1 auto-closed as invalid on 2021/03/22 19:41
linux-4.14 INFO: rcu detected stall in ipv6_rcv 1 1016d 1016d 0/1 auto-closed as invalid on 2020/08/24 07:16

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 23s! [syz-executor386:9617]
Modules linked in:
irq event stamp: 2778735
hardirqs last  enabled at (2778734): [<ffffffff81003ce4>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (2778735): [<ffffffff81003d00>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last  enabled at (2742486): [<ffffffff88400678>] __do_softirq+0x678/0x980 kernel/softirq.c:318
softirqs last disabled at (2742489): [<ffffffff813927d5>] invoke_softirq kernel/softirq.c:372 [inline]
softirqs last disabled at (2742489): [<ffffffff813927d5>] irq_exit+0x215/0x260 kernel/softirq.c:412
CPU: 0 PID: 9617 Comm: syz-executor386 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:41 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:321 [inline]
RIP: 0010:deref_stack_reg+0x9d/0x1d0 arch/x86/kernel/unwind_orc.c:331
Code: 3c 03 0f 8e 0a 01 00 00 41 8b 04 24 85 c0 74 62 49 8d 7c 24 08 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 00 01 00 00 49 8d 7c 24 10 4d 8b 74 24 08 48 b8 00 00 00 00
RSP: 0018:ffff8880ba006c98 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: dffffc0000000000 RBX: 1ffff11017400d94 RCX: 0000000000000000
RDX: 1ffff11017400dcd RSI: ffff8880ba0079f0 RDI: ffff8880ba006e68
RBP: ffff8880ba0079f0 R08: 0000000000000001 R09: 0000000000000001
R10: ffff8880ba006ebf R11: 0000000000074071 R12: ffff8880ba006e60
R13: ffff8880ba006ea0 R14: ffff8880ba006e60 R15: ffffffff8c066c2a
FS:  00007f0a3c191700(0000) GS:ffff8880ba000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555561442b8 CR3: 000000009bbec000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 unwind_next_frame+0xf83/0x1400 arch/x86/kernel/unwind_orc.c:555
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slab.c:3340 [inline]
 kmem_cache_alloc_node+0x133/0x3b0 mm/slab.c:3647
 __alloc_skb+0x71/0x560 net/core/skbuff.c:193
 alloc_skb include/linux/skbuff.h:995 [inline]
 sctp_packet_transmit+0x246/0x3660 net/sctp/output.c:584
 sctp_outq_flush_transports+0x19d/0x340 net/sctp/outqueue.c:1166
 sctp_outq_flush net/sctp/outqueue.c:1214 [inline]
 sctp_outq_uncork+0x185/0x200 net/sctp/outqueue.c:777
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1815 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x72a/0x5110 net/sctp/sm_sideeffect.c:1170
 sctp_assoc_bh_rcv+0x345/0x650 net/sctp/associola.c:1073
 sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:95
 sctp_rcv+0x1642/0x3300 net/sctp/input.c:268
 sctp6_rcv+0x12/0x30 net/sctp/ipv6.c:1072
 ip6_input_finish+0x46a/0x17a0 net/ipv6/ip6_input.c:385
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_input+0xcf/0x3c0 net/ipv6/ip6_input.c:428
 dst_input include/net/dst.h:461 [inline]
 ip6_rcv_finish+0x1d9/0x2f0 net/ipv6/ip6_input.c:76
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ipv6_rcv+0xf2/0x3f0 net/ipv6/ip6_input.c:273
 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:4954
 __netif_receive_skb+0x27/0x1c0 net/core/dev.c:5066
 process_backlog+0x241/0x700 net/core/dev.c:5849
 napi_poll net/core/dev.c:6280 [inline]
 net_rx_action+0x4ac/0xfb0 net/core/dev.c:6346
 __do_softirq+0x265/0x980 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1098
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:preempt_schedule_irq+0xab/0x140 kernel/sched/core.c:3744
Code: 29 f9 e8 58 3f 4f f9 4c 89 e8 48 c1 e8 03 80 3c 18 00 75 69 48 83 3d 9b 18 d9 01 00 74 5b fb 66 0f 1f 44 00 00 bf 01 00 00 00 <e8> 40 d1 ff ff 48 c7 c0 90 82 f1 89 48 c1 e8 03 80 3c 18 00 75 4b
RSP: 0018:ffff88809902ecb0 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e3053 RBX: dffffc0000000000 RCX: 1ffff11013195965
RDX: 0000000000000000 RSI: ffff888098cacb30 RDI: 0000000000000001
RBP: ffffed1013195850 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888098cac280
R13: ffffffff89f18298 R14: 0000000000000000 R15: 0000000000000000
 retint_kernel+0x1b/0x2d
RIP: 0010:should_resched arch/x86/include/asm/preempt.h:99 [inline]
RIP: 0010:__local_bh_enable_ip+0x18d/0x270 kernel/softirq.c:196
Code: 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 10 00 0f 85 dd 00 00 00 48 83 3d c8 5f b8 08 00 0f 84 8d 00 00 00 fb 66 0f 1f 44 00 00 <65> 8b 05 6c bc c8 7e 85 c0 74 7d 5b 5d 41 5c c3 80 3d f3 87 d5 09
RSP: 0018:ffff88809902ed88 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff13e3053 RBX: 0000000000000200 RCX: 1ffff11013195965
RDX: dffffc0000000000 RSI: ffff888098cacb30 RDI: ffff888098cacb04
RBP: ffffffff870217f6 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888098cac280
R13: 0000000000000010 R14: 000000000000000e R15: ffff888098e93040
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 rcu_read_unlock_bh include/linux/rcupdate.h:721 [inline]
 ip6_finish_output2+0x11a9/0x2290 net/ipv6/ip6_output.c:121
 ip6_finish_output+0x89b/0x10f0 net/ipv6/ip6_output.c:192
 NF_HOOK_COND include/linux/netfilter.h:278 [inline]
 ip6_output+0x205/0x770 net/ipv6/ip6_output.c:209
 dst_output include/net/dst.h:455 [inline]
 NF_HOOK include/linux/netfilter.h:289 [inline]
 ip6_xmit+0xdbf/0x20a0 net/ipv6/ip6_output.c:313
 sctp_v6_xmit+0x377/0x710 net/sctp/ipv6.c:229
 sctp_packet_transmit+0x1e21/0x3660 net/sctp/output.c:641
 sctp_outq_flush_transports+0x19d/0x340 net/sctp/outqueue.c:1166
 sctp_outq_flush net/sctp/outqueue.c:1214 [inline]
 sctp_outq_uncork+0x185/0x200 net/sctp/outqueue.c:777
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1815 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline]
 sctp_do_sm+0x72a/0x5110 net/sctp/sm_sideeffect.c:1170
 sctp_assoc_bh_rcv+0x345/0x650 net/sctp/associola.c:1073
 sctp_inq_push+0x1da/0x270 net/sctp/inqueue.c:95
 sctp_backlog_rcv+0x1e9/0x11e0 net/sctp/input.c:356
 sk_backlog_rcv include/net/sock.h:952 [inline]
 __release_sock+0x134/0x3a0 net/core/sock.c:2362
 release_sock+0x54/0x1b0 net/core/sock.c:2901
 sctp_wait_for_connect+0x301/0x530 net/sctp/socket.c:8635
 __sctp_connect+0xb6e/0xd00 net/sctp/socket.c:1273
 __sctp_setsockopt_connectx+0x132/0x1c0 net/sctp/socket.c:1381
 sctp_setsockopt_connectx_old net/sctp/socket.c:1397 [inline]
 sctp_setsockopt+0x29d9/0x4b40 net/sctp/socket.c:4354
 __sys_setsockopt+0x14d/0x240 net/socket.c:2013
 __do_sys_setsockopt net/socket.c:2024 [inline]
 __se_sys_setsockopt net/socket.c:2021 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2021
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f0a3c1e3749
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 00 00 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 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f0a3c191308 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f0a3c26c4c8 RCX: 00007f0a3c1e3749
RDX: 000000000000006b RSI: 0000000000000084 RDI: 0000000000000005
RBP: 00007f0a3c26c4c0 R08: 000000000000001c R09: 0000000000000000
R10: 000000002055bfe4 R11: 0000000000000246 R12: 00007f0a3c26c4cc
R13: 00007f0a3c2394cc R14: 0100000000000000 R15: 0000000000022000
----------------
Code disassembly (best guess):
   0:	3c 03                	cmp    $0x3,%al
   2:	0f 8e 0a 01 00 00    	jle    0x112
   8:	41 8b 04 24          	mov    (%r12),%eax
   c:	85 c0                	test   %eax,%eax
   e:	74 62                	je     0x72
  10:	49 8d 7c 24 08       	lea    0x8(%r12),%rdi
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 89 fa             	mov    %rdi,%rdx
  22:	48 c1 ea 03          	shr    $0x3,%rdx
  26:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
* 2a:	0f 85 00 01 00 00    	jne    0x130 <-- trapping instruction
  30:	49 8d 7c 24 10       	lea    0x10(%r12),%rdi
  35:	4d 8b 74 24 08       	mov    0x8(%r12),%r14
  3a:	48                   	rex.W
  3b:	b8 00 00 00 00       	mov    $0x0,%eax

Crashes (25):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets Title
ci2-linux-4-19 2021/12/10 22:21 linux-4.19.y 3f8a27f9e27b fc17c959 .config console log report syz C BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2022/07/30 08:56 linux-4.19.y 3f8a27f9e27b fef302b1 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2022/01/20 15:40 linux-4.19.y 3f8a27f9e27b b838eb76 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2022/01/18 21:14 linux-4.19.y 3f8a27f9e27b 731a2d23 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/12/10 14:02 linux-4.19.y 3f8a27f9e27b fc17c959 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/12/08 14:41 linux-4.19.y 3f8a27f9e27b a4a2a501 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/11/27 09:53 linux-4.19.y 3f8a27f9e27b 63eeac02 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/11/19 02:28 linux-4.19.y 3f8a27f9e27b 31a30fc0 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/11/14 01:40 linux-4.19.y 3f8a27f9e27b 75b04091 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/10/06 18:42 linux-4.19.y 6db10b4d5efd 62ee0987 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/08/06 18:03 linux-4.19.y 6ca2f514c578 6972b106 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/07/20 13:20 linux-4.19.y fcfbdfe9626e 1b201b48 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/07/11 12:12 linux-4.19.y fcfbdfe9626e 8f5a7b8c .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/06/24 21:16 linux-4.19.y eb575cd5d7f6 0edbbe31 .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2021/04/08 17:18 linux-4.19.y b4454811f122 6a81331a .config console log report info BUG: soft lockup in ipv6_rcv
ci2-linux-4-19 2022/06/19 10:53 linux-4.19.y 3f8a27f9e27b 8f633d84 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2022/01/26 01:08 linux-4.19.y 3f8a27f9e27b 2cbffd88 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/11/29 13:32 linux-4.19.y 3f8a27f9e27b 63eeac02 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/11/29 07:18 linux-4.19.y 3f8a27f9e27b 63eeac02 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/11/29 05:42 linux-4.19.y 3f8a27f9e27b 63eeac02 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/11/27 14:16 linux-4.19.y 3f8a27f9e27b 63eeac02 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/11/16 07:34 linux-4.19.y 3f8a27f9e27b 75b04091 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/09/17 16:39 linux-4.19.y b172b44fcb17 70b76c1d .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/09/14 22:22 linux-4.19.y b172b44fcb17 07e953c1 .config console log report info INFO: rcu detected stall in ipv6_rcv
ci2-linux-4-19 2021/07/09 21:29 linux-4.19.y 9f84340f012e 8f5a7b8c .config console log report info INFO: rcu detected stall in ipv6_rcv
* Struck through repros no longer work on HEAD.