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BUG: soft lockup in br_multicast_port_group_expired

Status: premoderation: reported on 2024/08/23 20:07
Reported-by: syzbot+425bfbe1e51dd4f8cf8f@syzkaller.appspotmail.com
First crash: 23d, last: 23d
▶ ▼ Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 BUG: soft lockup in br_multicast_port_group_expired 1 31d 31d 0/2 premoderation: reported on 2024/08/16 17:45
android-6-1 BUG: soft lockup in br_multicast_port_group_expired 2 6d17h 93d 0/2 premoderation: reported on 2024/06/15 09:56
android-54 BUG: soft lockup in br_multicast_port_group_expired 1 103d 103d 0/2 auto-obsoleted due to no activity on 2024/09/03 00:58
linux-5.15 INFO: rcu detected stall in br_multicast_port_group_expired 1 74d 74d 0/3 upstream: reported on 2024/07/03 20:33

Sample crash report:
watchdog: BUG: soft lockup - CPU#0 stuck for 123s! [syz.0.403:2976]
Modules linked in:
CPU: 0 PID: 2976 Comm: syz.0.403 Tainted: G        W         5.10.223-syzkaller-01561-g0890c03b8b7d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:__bpf_trace_run kernel/trace/bpf_trace.c:2061 [inline]
RIP: 0010:bpf_trace_run2+0xdc/0x280 kernel/trace/bpf_trace.c:2098
Code: bd 32 00 4c 89 74 24 48 e8 c1 2e e2 ff 0f 1f 44 00 00 e8 17 24 f5 ff 4d 8d 77 38 49 83 c7 30 4c 89 f8 48 c1 e8 03 80 3c 18 00 <74> 08 4c 89 ff e8 da bc 32 00 4c 89 e7 4c 89 f6 41 ff 17 e8 dc 2e
RSP: 0000:ffffc90000007800 EFLAGS: 00000246
RAX: 1ffff92000017606 RBX: dffffc0000000000 RCX: ffff88810ec50000
RDX: 0000000000000103 RSI: ffffffff83be4334 RDI: ffffc90000007848
RBP: ffffc900000078b8 R08: 0000000000000003 R09: ffffc90000007694
R10: 00000000fd7ef38a R11: 000000000f6e051b R12: ffffc90000007840
R13: ffffffff83be4334 R14: ffffc900000bb038 R15: ffffc900000bb030
FS:  00007fdb2241f6c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b33917ff8 CR3: 0000000120bae000 CR4: 00000000003506b0
DR0: 0010000010000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __bpf_trace_kmem_free+0x6f/0x90 include/trace/events/kmem.h:118
 trace_kmem_cache_free include/trace/events/kmem.h:145 [inline]
 kmem_cache_free+0x1c0/0x1e0 mm/slub.c:3220
 kfree_skbmem+0x104/0x170
 __kfree_skb net/core/skbuff.c:695 [inline]
 consume_skb+0xb4/0x250 net/core/skbuff.c:851
 netlink_broadcast_filtered+0x114e/0x1270 net/netlink/af_netlink.c:1532
 netlink_broadcast net/netlink/af_netlink.c:1554 [inline]
 nlmsg_multicast include/net/netlink.h:1033 [inline]
 nlmsg_notify+0x101/0x1c0 net/netlink/af_netlink.c:2543
 rtnl_notify+0x9c/0xd0 net/core/rtnetlink.c:737
 br_mdb_notify+0x9c3/0xca0 net/bridge/br_mdb.c:599
 br_multicast_del_pg+0x4d8/0xb40 net/bridge/br_multicast.c:597
 br_multicast_find_del_pg net/bridge/br_multicast.c:629 [inline]
 br_multicast_port_group_expired+0x714/0x870 net/bridge/br_multicast.c:659
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1450
 expire_timers kernel/time/timer.c:1495 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1789
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1802
 __do_softirq+0x268/0x5bb kernel/softirq.c:309
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x60/0x80 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:405 [inline]
 __irq_exit_rcu+0x128/0x150 kernel/softirq.c:435
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:447
 sysvec_apic_timer_interrupt+0xbf/0xe0 arch/x86/kernel/apic/apic.c:1094
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
RIP: 0010:__schedule+0x0/0x1330 kernel/sched/core.c:4686
Code: 54 bf 86 4c 89 25 a0 4e 0e 02 eb 05 e8 79 a3 b9 fc 48 c7 c7 60 fc 12 87 e8 6d 33 01 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc <55> 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 e4 e0 48 81 ec c0 00
RSP: 0000:ffffc900010b7d58 EFLAGS: 00000246
RAX: 1ffff11021d8a146 RBX: 1ffff92000216fb0 RCX: ffffffff84b24700
RDX: 1ffffffff0e10800 RSI: 0000000000000000 RDI: 0000000000000001
RBP: ffffc900010b7df0 R08: ffffffff87084008 R09: ffffffff87084018
R10: ffffffff87084010 R11: ffffffff87084003 R12: ffffc900010b7d80
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000216fac
 irqentry_exit_cond_resched kernel/entry/common.c:365 [inline]
 irqentry_exit+0x4f/0x60 kernel/entry/common.c:395
 sysvec_irq_work+0xc8/0xd0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:661
RIP: 0010:exit_to_user_mode_loop+0x41/0xd0 kernel/entry/common.c:159
Code: 89 fe eb 22 e8 90 4a 52 00 e8 8b 8f f0 00 fa 65 48 8b 05 d2 08 a9 7e 48 8b 18 f7 c3 0e 30 08 00 0f 84 87 00 00 00 fb f6 c3 08 <74> 05 e8 08 b4 57 03 f7 c3 00 10 00 00 74 08 4c 89 f7 e8 18 71 34
RSP: 0000:ffffc900010b7ee0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000010000
RDX: 1ffffffff0e10800 RSI: 0000000000000008 RDI: ffffc900010b7f58
RBP: ffffc900010b7ef0 R08: ffffffff87084008 R09: ffffffff87084018
R10: ffffffff87084010 R11: ffffffff87084003 R12: ffffffff84c00c7a
R13: 0000000000000000 R14: ffffc900010b7f58 R15: 0000000000000000
 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline]
 irqentry_exit_to_user_mode+0x4e/0x80 kernel/entry/common.c:287
 irqentry_exit+0x12/0x60 kernel/entry/common.c:375
 sysvec_apic_timer_interrupt+0xcb/0xe0 arch/x86/kernel/apic/apic.c:1094
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
RIP: 0033:0x7fdb236683c7
Code: 83 c4 08 c3 0f 1f 80 00 00 00 00 48 83 ec 08 48 89 f2 48 63 ff 4c 89 d6 41 51 31 c0 4d 89 c1 49 89 c8 4c 89 d9 e8 99 9a 13 00 <5a> 59 48 83 c4 08 c3 66 90 41 57 41 56 41 55 49 89 f5 41 54 49 29
RSP: 002b:00007fdb2241f040 EFLAGS: 00000217
RAX: 0000000000000000 RBX: 00007fdb2393df80 RCX: 00007fdb237a1e79
RDX: 00000000200006c0 RSI: 0000000000005452 RDI: 0000000000000009
RBP: 00007fdb2380f93e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fdb2393df80 R15: 00007ffc06843778
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 1413 Comm: syz.0.207 Tainted: G        W         5.10.223-syzkaller-01561-g0890c03b8b7d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:25 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:221 [inline]
RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:162 [inline]
RIP: 0010:wrmsr arch/x86/include/asm/msr.h:273 [inline]
RIP: 0010:native_apic_msr_write+0x39/0x50 arch/x86/include/asm/apic.h:208
Code: 74 05 83 ff 30 75 12 5d c3 81 ff d0 00 00 00 74 f6 81 ff e0 00 00 00 74 ee c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <0f> 1f 44 00 00 eb d6 89 f6 31 d2 e8 67 95 3e 01 5d c3 0f 1f 44 00
RSP: 0018:ffffc90000170158 EFLAGS: 00000046
RAX: 0000000000000153 RBX: ffffffff85dc3988 RCX: 0000000000000838
RDX: 0000000000000000 RSI: 0000000000000153 RDI: 0000000000000838
RBP: ffffc90000170158 R08: ffffffff815df0f1 R09: ffffffff815df07d
R10: 0000000000000002 R11: ffff888110092780 R12: 0000000000001537
R13: dffffc0000000000 R14: 0000000000000153 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff7d2f7e136 CR3: 000000014be7a000 CR4: 00000000003506a0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 apic_write arch/x86/include/asm/apic.h:396 [inline]
 lapic_next_event+0x5f/0x70 arch/x86/kernel/apic/apic.c:466
 clockevents_program_event+0x1a7/0x2c0 kernel/time/clockevents.c:334
 tick_program_event+0x9f/0x120 kernel/time/tick-oneshot.c:44
 hrtimer_interrupt+0x4cf/0x8b0 kernel/time/hrtimer.c:1722
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1083 [inline]
 __sysvec_apic_timer_interrupt+0xfd/0x3c0 arch/x86/kernel/apic/apic.c:1100
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline]
 sysvec_apic_timer_interrupt+0xba/0xe0 arch/x86/kernel/apic/apic.c:1094
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:25 [inline]
RIP: 0010:static_key_false include/linux/jump_label.h:221 [inline]
RIP: 0010:trace_net_dev_queue include/trace/events/net.h:143 [inline]
RIP: 0010:__dev_queue_xmit+0xa12/0x28e0 net/core/dev.c:4153
Code: ff 49 89 c4 48 8d 58 08 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 48 89 df e8 01 5d e3 fd 4c 8b 33 <0f> 1f 44 00 00 e8 14 c4 a5 fd 4d 89 f5 49 c1 ed 03 48 b8 00 00 00
RSP: 0018:ffffc90000170420 EFLAGS: 00000246
RAX: 1ffff11022ed7b81 RBX: ffff8881176bdc08 RCX: dffffc0000000000
RDX: 0000000000000500 RSI: 0000000000000001 RDI: 0000000000000001
RBP: ffffc90000170610 R08: ffffffff83c4d874 R09: ffffed103ee2ae72
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff8881176bdc00
R13: 0000000000000000 R14: ffff88812519ac00 R15: ffff88813f0ad058
 dev_queue_xmit+0x17/0x20 net/core/dev.c:4223
 neigh_resolve_output+0x6b8/0x760 net/core/neighbour.c:1509
 neigh_output include/net/neighbour.h:517 [inline]
 ip6_finish_output2+0xf21/0x1850 net/ipv6/ip6_output.c:145
 __ip6_finish_output+0x5ec/0x780 net/ipv6/ip6_output.c:216
 ip6_finish_output+0x34/0x1e0 net/ipv6/ip6_output.c:226
 NF_HOOK_COND include/linux/netfilter.h:288 [inline]
 ip6_output+0x1f7/0x4c0 net/ipv6/ip6_output.c:249
 dst_output include/net/dst.h:437 [inline]
 NF_HOOK include/linux/netfilter.h:299 [inline]
 ndisc_send_skb+0x6e9/0xc00 net/ipv6/ndisc.c:509
 ndisc_send_rs+0x532/0x6a0 net/ipv6/ndisc.c:703
 addrconf_rs_timer+0x2d1/0x600 net/ipv6/addrconf.c:3963
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1450
 expire_timers kernel/time/timer.c:1495 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1789
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1802
 __do_softirq+0x268/0x5bb kernel/softirq.c:309
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0x60/0x80 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:405 [inline]
 __irq_exit_rcu+0x128/0x150 kernel/softirq.c:435
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:447
 sysvec_apic_timer_interrupt+0xbf/0xe0 arch/x86/kernel/apic/apic.c:1094
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
RIP: 0010:unwind_done arch/x86/include/asm/unwind.h:46 [inline]
RIP: 0010:arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:24
Code: 32 48 8d 9d 70 ff ff ff 48 89 df e8 bd df 05 00 48 85 c0 74 1e 4c 89 f7 48 89 c6 41 ff d5 84 c0 74 11 48 89 df e8 d3 e0 05 00 <83> bd 70 ff ff ff 00 75 d5 65 48 8b 04 25 28 00 00 00 48 3b 45 d0
RSP: 0018:ffffc90000dd7400 EFLAGS: 00000282
RAX: 0000000000dd7401 RBX: ffffc90000dd7400 RCX: 0000000000dd7401
RDX: 1ffff920001bae82 RSI: ffffc90000dd7b78 RDI: ffffc90000dd7458
RBP: ffffc90000dd7490 R08: ffffc90000dd74e8 R09: 0000000000000009
R10: ffffc90000dd74f0 R11: dffffc0000000001 R12: ffff888110092780
R13: ffffffff8159b260 R14: ffffc90000dd74e0 R15: 0000000000000000
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:121
 save_stack+0x97/0x240 mm/page_owner.c:146
 __reset_page_owner+0x36/0x150 mm/page_owner.c:174
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2ae/0x2d0 mm/page_alloc.c:3336
 free_unref_page mm/page_alloc.c:3391 [inline]
 free_the_page+0x9e/0x370 mm/page_alloc.c:5407
 __free_pages+0x67/0xc0 mm/page_alloc.c:5418
 __vunmap+0x7bc/0x8f0 mm/vmalloc.c:2301
 __vfree mm/vmalloc.c:2349 [inline]
 vfree+0x5c/0x80 mm/vmalloc.c:2380
 kcov_put kernel/kcov.c:408 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:510
 __fput+0x33d/0x7b0 fs/file_table.c:281
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x129/0x190 kernel/task_work.c:165
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0xc83/0x2a50 kernel/exit.c:863
 do_group_exit+0x141/0x310 kernel/exit.c:985
 get_signal+0x10a0/0x1410 kernel/signal.c:2782
 arch_do_signal_or_restart+0xbd/0x17c0 arch/x86/kernel/signal.c:805
 handle_signal_work kernel/entry/common.c:145 [inline]
 exit_to_user_mode_loop+0x9b/0xd0 kernel/entry/common.c:169
 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline]
 irqentry_exit_to_user_mode+0x4e/0x80 kernel/entry/common.c:287
 irqentry_exit+0x12/0x60 kernel/entry/common.c:375
 sysvec_apic_timer_interrupt+0xcb/0xe0 arch/x86/kernel/apic/apic.c:1094
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:635
RIP: 0033:0x7f8e577ade79
Code: Unable to access opcode bytes at RIP 0x7f8e577ade4f.
RSP: 002b:00007f8e5640a038 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 00007f8e5794a058 RCX: 00007f8e577ade79
RDX: 00000000200006c0 RSI: 0000000000005452 RDI: 000000000000000c
RBP: 00007f8e5781b93e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8e5794a058 R15: 00007fff97d2c288

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/23 20:06 android13-5.10-lts 0890c03b8b7d d7d32352 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10-perf BUG: soft lockup in br_multicast_port_group_expired
* Struck through repros no longer work on HEAD.