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BUG: soft lockup in br_multicast_port_group_expired

Status: auto-obsoleted due to no activity on 2025/01/02 19:42
Reported-by: syzbot+3d35fb6b52ea7a438760@syzkaller.appspotmail.com
First crash: 678d, last: 567d
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 BUG: soft lockup in br_multicast_port_group_expired 1 2 533d 616d 0/2 auto-obsoleted due to no activity on 2025/02/05 03:41
android-54 BUG: soft lockup in br_multicast_port_group_expired 1 1 688d 688d 0/2 auto-obsoleted due to no activity on 2024/09/03 00:58
upstream BUG: soft lockup in br_multicast_port_group_expired net 1 1 114d 114d 0/29 closed as invalid on 2026/03/06 16:20
android-54 BUG: soft lockup in br_multicast_port_group_expired (2) 1 2 362d 401d 0/2 auto-obsoleted due to no activity on 2025/07/26 14:48
android-5-10 BUG: soft lockup in br_multicast_port_group_expired 1 1 609d 609d 0/2 auto-obsoleted due to no activity on 2024/11/21 20:11
linux-5.15 INFO: rcu detected stall in br_multicast_port_group_expired 1 1 660d 660d 0/3 auto-obsoleted due to no activity on 2024/10/11 20:34

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 226s! [syz.0.399:1767]
Modules linked in:
CPU: 1 PID: 1767 Comm: syz.0.399 Not tainted 6.1.99-syzkaller-00108-gd4dab27b9d1c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:update_stack_state+0x33b/0x460 arch/x86/kernel/unwind_frame.c:243
Code: 75 b8 74 66 45 31 f6 e9 af 00 00 00 48 8b 45 d0 4c 8d 70 38 4c 89 f0 48 c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 80 3c 38 00 <74> 08 4c 89 f7 e8 5b 0c 85 00 48 8b 45 c0 49 89 06 48 8b 4d 90 42
RSP: 0018:ffffc900001b0370 EFLAGS: 00000246
RAX: 1ffff9200003609f RBX: ffffc900001b04e8 RCX: ffffc900012f7b60
RDX: 1ffff9200003609a RSI: ffffc900012f7b50 RDI: ffffc900001b0518
RBP: ffffc900001b0428 R08: ffffc900001b05a8 R09: 000000000000002b
R10: ffffc900001b05b0 R11: dffffc0000000001 R12: 1ffff920000360a0
R13: 0000000000000000 R14: ffffc900001b04f8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200012c0 CR3: 000000013f695000 CR4: 00000000003506a0
DR0: 0000000020000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 unwind_next_frame+0x3cb/0x700 arch/x86/kernel/unwind_frame.c:315
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x131/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1745 [inline]
 slab_free_freelist_hook mm/slub.c:1771 [inline]
 slab_free mm/slub.c:3684 [inline]
 __kmem_cache_free+0x218/0x3b0 mm/slub.c:3697
 kfree+0x7a/0xf0 mm/slab_common.c:1009
 skb_free_head net/core/skbuff.c:762 [inline]
 skb_release_data+0x616/0x840 net/core/skbuff.c:791
 skb_release_all net/core/skbuff.c:856 [inline]
 __kfree_skb net/core/skbuff.c:870 [inline]
 consume_skb+0xac/0x250 net/core/skbuff.c:1035
 netlink_broadcast+0x103c/0x1160 net/netlink/af_netlink.c:1524
 nlmsg_multicast include/net/netlink.h:1071 [inline]
 nlmsg_notify+0xfb/0x1c0 net/netlink/af_netlink.c:2561
 rtnl_notify+0x9c/0xd0 net/core/rtnetlink.c:767
 br_mdb_notify+0x701/0x9b0 net/bridge/br_mdb.c:578
 br_multicast_del_pg+0x4e2/0xb50 net/bridge/br_multicast.c:691
 br_multicast_find_del_pg net/bridge/br_multicast.c:723 [inline]
 br_multicast_port_group_expired+0x716/0x870 net/bridge/br_multicast.c:753
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1510
 expire_timers kernel/time/timer.c:1555 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1826
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1839
 handle_softirqs+0x1db/0x650 kernel/softirq.c:617
 __do_softirq kernel/softirq.c:655 [inline]
 invoke_softirq kernel/softirq.c:472 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:704
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:716
 sysvec_apic_timer_interrupt+0x9a/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__schedule+0xcbd/0x1560
Code: 44 24 68 42 0f b6 04 28 84 c0 0f 85 83 02 00 00 41 80 24 24 fc 4c 89 f7 48 8b 74 24 20 e8 db f3 e1 fb 48 89 c7 e8 e3 0c 32 fc <48> 8b 44 24 70 48 c7 84 24 80 00 00 00 0e 36 e0 45 49 c7 44 05 00
RSP: 0018:ffffc900012f6ee0 EFLAGS: 00000282
RAX: 0000000080000001 RBX: 1ffff1103ede70fc RCX: 0000000000000002
RDX: 0000000000000001 RSI: 0000000000000008 RDI: 0000000000000001
RBP: ffffc900012f6ff0 R08: dffffc0000000000 R09: ffffed1022ac6ca9
R10: 0000000000000000 R11: dffffc0000000001 R12: ffff888115636540
R13: dffffc0000000000 R14: 0000000000000000 R15: ffff8881f6f387e0
 preempt_schedule_irq+0xc7/0x140 kernel/sched/core.c:7059
 raw_irqentry_exit_cond_resched+0x2a/0x30 kernel/entry/common.c:396
 irqentry_exit+0x30/0x40 kernel/entry/common.c:439
 sysvec_apic_timer_interrupt+0x55/0xc0 arch/x86/kernel/apic/apic.c:1106
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:is_last_frame arch/x86/kernel/unwind_frame.c:87 [inline]
RIP: 0010:is_last_task_frame arch/x86/kernel/unwind_frame.c:156 [inline]
RIP: 0010:unwind_next_frame+0xb2/0x700 arch/x86/kernel/unwind_frame.c:276
Code: 84 15 85 00 48 ba 00 00 00 00 00 fc ff df f6 03 03 0f 85 f0 04 00 00 49 8d 5e 38 48 89 d8 48 c1 e8 03 48 89 45 b0 80 3c 10 00 <74> 12 48 89 df e8 54 15 85 00 48 ba 00 00 00 00 00 fc ff df 48 89
RSP: 0018:ffffc900012f7198 EFLAGS: 00000246
RAX: 1ffff9200025ee4b RBX: ffffc900012f7258 RCX: ffffffff879a3000
RDX: dffffc0000000000 RSI: ffffffff81b7b24d RDI: ffffc900012f7220
RBP: ffffc900012f7210 R08: ffffc900012f7308 R09: 0000000000000000
R10: ffffc900012f7310 R11: dffffc0000000001 R12: 0000000000000000
R13: ffffffff8165c4d0 R14: ffffc900012f7220 R15: 1ffff9200025ee44
 arch_stack_walk+0x10d/0x140 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:122
 save_stack+0xf6/0x1e0 mm/page_owner.c:147
 __reset_page_owner+0x54/0x190 mm/page_owner.c:168
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1498 [inline]
 free_pcp_prepare mm/page_alloc.c:1572 [inline]
 free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3498
 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3594
 free_the_page mm/page_alloc.c:798 [inline]
 __free_pages+0x61/0xf0 mm/page_alloc.c:5803
 __vunmap+0x9f3/0xb60 mm/vmalloc.c:2728
 __vfree mm/vmalloc.c:2776 [inline]
 vfree+0x5c/0x80 mm/vmalloc.c:2807
 kcov_put kernel/kcov.c:428 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:524
 __fput+0x1e5/0x870 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x24d/0x2e0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xbd5/0x2b80 kernel/exit.c:877
 do_group_exit+0x21a/0x2d0 kernel/exit.c:1027
 get_signal+0x169d/0x1820 kernel/signal.c:2880
 arch_do_signal_or_restart+0xb0/0x16f0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x26/0x130 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe35df7dff9
Code: Unable to access opcode bytes at 0x7fe35df7dfcf.
RSP: 002b:00007fe35edc3038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000006 RBX: 00007fe35e135f80 RCX: 00007fe35df7dff9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fe35dff0296 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe35e135f80 R15: 00007ffc002e9108
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 514 Comm: kworker/u4:4 Not tainted 6.1.99-syzkaller-00108-gd4dab27b9d1c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:453 [inline]
RIP: 0010:smp_call_function_many_cond+0x851/0x930 kernel/smp.c:998
Code: 3e 44 89 fe 83 e6 01 31 ff e8 fb 9e 09 00 41 83 e7 01 49 bf 00 00 00 00 00 fc ff df 75 0a e8 36 9b 09 00 e9 2f ff ff ff f3 90 <42> 0f b6 04 3b 84 c0 75 14 41 f7 06 01 00 00 00 0f 84 12 ff ff ff
RSP: 0018:ffffc90000a37840 EFLAGS: 00000293
RAX: ffffffff816c083c RBX: 1ffff1103ede7885 RCX: ffff88811e891440
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90000a37958 R08: ffffffff816c0805 R09: ffffed103edc71fb
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001
R13: 0000000800000000 R14: ffff8881f6f3c428 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6aa9f26110 CR3: 000000000700f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 on_each_cpu_cond_mask+0x40/0x80 kernel/smp.c:1166
 on_each_cpu include/linux/smp.h:71 [inline]
 text_poke_sync arch/x86/kernel/alternative.c:1334 [inline]
 text_poke_bp_batch+0x1e9/0x730 arch/x86/kernel/alternative.c:1534
 text_poke_flush arch/x86/kernel/alternative.c:1725 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1732
 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:146
 __jump_label_update+0x36a/0x380 kernel/jump_label.c:455
 jump_label_update+0x3af/0x450 kernel/jump_label.c:801
 static_key_enable_cpuslocked+0x12f/0x250 kernel/jump_label.c:177
 static_key_enable+0x1a/0x30 kernel/jump_label.c:190
 toggle_allocation_gate+0xbf/0x450 mm/kfence/core.c:804
 process_one_work+0x73d/0xcb0 kernel/workqueue.c:2299
 worker_thread+0xa60/0x1260 kernel/workqueue.c:2446
 kthread+0x26d/0x300 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
NMI backtrace for cpu 1
CPU: 1 PID: 1767 Comm: syz.0.399 Tainted: G             L     6.1.99-syzkaller-00108-gd4dab27b9d1c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
RIP: 0010:kvm_set_cpu_l1tf_flush_l1d+0x10/0x20 arch/x86/include/asm/hardirq.h:67
Code: c7 c7 20 06 10 87 e8 df fc ee 03 5d c3 cc cc cc cc cc cc cc cc cc cc cc cc cc 55 48 89 e5 48 c7 c7 80 08 86 85 e8 d0 42 ea 03 <65> c6 05 0a db d3 7e 01 5d c3 66 0f 1f 44 00 00 55 48 89 e5 41 56
RSP: 0018:ffffc900001b0bd8 EFLAGS: 00000082
RAX: 0000000000000001 RBX: ffffc900001b0c08 RCX: ffffffff85400f0f
RDX: 0000000000000000 RSI: ffffffff85860880 RDI: ffffffff85ea00c0
RBP: ffffc900001b0bd8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000200012c0 CR3: 000000013f695000 CR4: 00000000003506a0
DR0: 0000000020000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 sysvec_irq_work+0x17/0xb0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x1b/0x20 arch/x86/include/asm/idtentry.h:679
RIP: 0010:can_stat_update+0x715/0xd20 net/can/proc.c:138
Code: 03 00 48 83 c3 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 a0 7e 1d fd 48 ff 03 eb 14 <e8> 06 3f d6 fc 4c 8b 65 c8 4c 8b 6d b8 eb 05 e8 f7 3e d6 fc 48 8b
RSP: 0018:ffffc900001b0cb8 EFLAGS: 00000293
RAX: 0000000000000101 RBX: 0000000000000000 RCX: ffff888115636540
RDX: 0000000000000101 RSI: 0000000000000000 RDI: 028f5c28f5c28f5c
RBP: ffffc900001b0d30 R08: ffffffff849f6329 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: ffff88811a6232a8
R13: 028f5c28f5c28f5c R14: ffff88811a6232e0 R15: 1ffff110212eac23
 call_timer_fn+0x3b/0x2d0 kernel/time/timer.c:1510
 expire_timers kernel/time/timer.c:1555 [inline]
 __run_timers+0x72a/0xa10 kernel/time/timer.c:1826
 run_timer_softirq+0x69/0xf0 kernel/time/timer.c:1839
 handle_softirqs+0x1db/0x650 kernel/softirq.c:617
 __do_softirq kernel/softirq.c:655 [inline]
 invoke_softirq kernel/softirq.c:472 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:704
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:716
 sysvec_apic_timer_interrupt+0x9a/0xc0 arch/x86/kernel/apic/apic.c:1106
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0x56/0x80 kernel/locking/spinlock.c:194
Code: f3 0d 87 e8 9c ad 9c fc 48 83 3d 54 be ed 01 00 74 34 48 89 df e8 6e 0f 00 00 90 41 f7 c6 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 15 52 2f fc 65 8b 05 56 38 e2 7a 85 c0 74 05 5b 41 5e 5d c3 e8
RSP: 0018:ffffc900012f7280 EFLAGS: 00000206
RAX: 0000000000000001 RBX: ffffffff871b5fd8 RCX: dffffc0000000000
RDX: ffffc900000e7d88 RSI: 0000000000000246 RDI: 0000000000000001
RBP: ffffc900012f7290 R08: dffffc0000000000 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffc900000e7d88 R14: 0000000000000246 R15: ffffffff871b5fd8
 swake_up_one+0x152/0x170 kernel/sched/swait.c:53
 swake_up_one_online+0x6b/0x110 kernel/rcu/tree.c:1082
 rcu_gp_kthread_wake kernel/rcu/tree.c:1110 [inline]
 rcu_report_qs_rsp kernel/rcu/tree.c:1931 [inline]
 rcu_report_unblock_qs_rnp kernel/rcu/tree.c:2035 [inline]
 rcu_preempt_deferred_qs_irqrestore+0x8b3/0x9e0 kernel/rcu/tree_plugin.h:557
 rcu_read_unlock_special+0xdb/0x4e0 kernel/rcu/tree_plugin.h:681
 __rcu_read_unlock+0x7e/0xd0 kernel/rcu/tree_plugin.h:426
 rcu_read_unlock include/linux/rcupdate.h:832 [inline]
 page_ext_put+0x1c/0x30 mm/page_ext.c:187
 __reset_page_owner+0x175/0x190 mm/page_owner.c:176
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1498 [inline]
 free_pcp_prepare mm/page_alloc.c:1572 [inline]
 free_unref_page_prepare+0x83d/0x850 mm/page_alloc.c:3498
 free_unref_page+0xb2/0x5c0 mm/page_alloc.c:3594
 free_the_page mm/page_alloc.c:798 [inline]
 __free_pages+0x61/0xf0 mm/page_alloc.c:5803
 __vunmap+0x9f3/0xb60 mm/vmalloc.c:2728
 __vfree mm/vmalloc.c:2776 [inline]
 vfree+0x5c/0x80 mm/vmalloc.c:2807
 kcov_put kernel/kcov.c:428 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:524
 __fput+0x1e5/0x870 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x24d/0x2e0 kernel/task_work.c:179
 exit_task_work include/linux/task_work.h:38 [inline]
 do_exit+0xbd5/0x2b80 kernel/exit.c:877
 do_group_exit+0x21a/0x2d0 kernel/exit.c:1027
 get_signal+0x169d/0x1820 kernel/signal.c:2880
 arch_do_signal_or_restart+0xb0/0x16f0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x74/0xa0 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x26/0x130 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe35df7dff9
Code: Unable to access opcode bytes at 0x7fe35df7dfcf.
RSP: 002b:00007fe35edc3038 EFLAGS: 00000246 ORIG_RAX: 000000000000012a
RAX: 0000000000000006 RBX: 00007fe35e135f80 RCX: 00007fe35df7dff9
RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fe35dff0296 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fe35e135f80 R15: 00007ffc002e9108
 </TASK>

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/04 19:32 android14-6.1 d4dab27b9d1c d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1-perf BUG: soft lockup in br_multicast_port_group_expired
2024/09/10 01:58 android14-6.1 04212acc42d4 784df80e .config console log report info ci2-android-6-1-perf BUG: soft lockup in br_multicast_port_group_expired
2024/06/15 09:55 android14-6.1 25216be1ac5e f429ab00 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1-perf BUG: soft lockup in br_multicast_port_group_expired
* Struck through repros no longer work on HEAD.