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BUG: soft lockup in br_multicast_group_expired (2)

Status: auto-obsoleted due to no activity on 2025/03/05 23:26
Reported-by: syzbot+0ce6a24666b82c75e1fe@syzkaller.appspotmail.com
First crash: 256d, last: 256d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-6-1 BUG: soft lockup in br_multicast_group_expired 1 1 365d 365d 0/2 auto-obsoleted due to no activity on 2024/11/17 00:46
android-54 BUG: soft lockup in br_multicast_group_expired 1 2 103d 143d 0/2 auto-obsoleted due to no activity on 2025/08/06 07:32
upstream BUG: soft lockup in br_multicast_group_expired net 1 1 2089d 2089d 0/29 closed as invalid on 2019/11/30 16:54
android-5-10 BUG: soft lockup in br_multicast_group_expired 1 1 377d 377d 0/2 auto-obsoleted due to no activity on 2024/11/05 04:11

Sample crash report:
watchdog: BUG: soft lockup - CPU#1 stuck for 123s! [syz.3.913:7309]
Modules linked in:
CPU: 1 PID: 7309 Comm: syz.3.913 Not tainted 5.10.226-syzkaller-00444-g220ce693f83f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:stack_trace_consume_entry+0x13b/0x290 kernel/stacktrace.c:94
Code: 4c 8b 55 c8 4c 89 fe 4c 89 f2 48 89 33 41 8b 1a 41 0f b6 04 14 84 c0 0f 85 37 01 00 00 41 3b 18 0f 92 c0 48 83 c4 20 5b 41 5c <41> 5d 41 5e 41 5f 5d c3 44 89 d1 80 e1 07 80 c1 03 38 c1 0f 8c e2
RSP: 0018:ffffc90000170518 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffc90000170540 RCX: 0000000000170501
RDX: dffffc0000000000 RSI: ffffffff8128b66d RDI: ffffc9000017062c
RBP: ffffc90000170530 R08: ffffc90000170628 R09: 000000000000001f
R10: ffffc90000170630 R11: dffffc0000000001 R12: ffff888144e43b40
R13: 1ffff9200002e0c5 R14: ffffc900001706d0 R15: 1ffff9200002e0c6
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa54b4ad58e CR3: 00000001059fb000 CR4: 00000000003506a0
DR0: 0000000000000008 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 arch_stack_walk+0x101/0x140 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x113/0x1c0 kernel/stacktrace.c:121
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc0/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kmem_cache_free+0xa9/0x1e0 mm/slub.c:3219
 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:2542
 rtnl_notify+0x9c/0xd0 net/core/rtnetlink.c:737
 br_mdb_notify+0x9c3/0xca0 net/bridge/br_mdb.c:599
 br_multicast_host_leave net/bridge/br_multicast.c:1218 [inline]
 br_multicast_group_expired+0x30a/0x5e0 net/bridge/br_multicast.c:541
 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:lru_cache_disabled+0x0/0x40 mm/swap.c:971
Code: 3f d8 ff e8 f2 f2 ff ff 5d c3 55 48 89 e5 e8 57 3f d8 ff 31 ff e8 70 f4 ff ff 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <55> 48 89 e5 53 e8 36 3f d8 ff 48 c7 c7 80 f7 0b 87 be 04 00 00 00
RSP: 0018:ffffc900014a74d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888144e43b40
RDX: 0000000000000000 RSI: 00000000000001fe RDI: 0000000000000085
RBP: ffffc900014a7710 R08: ffffffff81a0b77e R09: fffff94000878417
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffea00043c2080 R14: ffff88813aeaed08 R15: 00007f0845da1000
 unmap_single_vma mm/memory.c:1551 [inline]
 unmap_vmas+0x37f/0x4f0 mm/memory.c:1583
 exit_mmap+0x2f2/0x5c0 mm/mmap.c:3355
 __mmput+0x95/0x2d0 kernel/fork.c:1153
 mmput+0x59/0x170 kernel/fork.c:1176
 exit_mm kernel/exit.c:539 [inline]
 do_exit+0xbda/0x2a50 kernel/exit.c:850
 do_group_exit+0x141/0x310 kernel/exit.c:985
 get_signal+0x10a0/0x1410 kernel/signal.c:2793
 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]
 syscall_exit_to_user_mode+0xa2/0x1a0 kernel/entry/common.c:274
 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0846c1df19
Code: Unable to access opcode bytes at RIP 0x7f0846c1deef.
RSP: 002b:00007f0845274058 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f0846de4080 RCX: 00007f0846c1df19
RDX: 00000000200006c0 RSI: 0000000000005452 RDI: 0000000000000009
RBP: 00007f0846c91986 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0846de4080 R15: 00007fff29077b08
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 7360 Comm: kworker/u4:6 Not tainted 5.10.226-syzkaller-00444-g220ce693f83f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: events_unbound toggle_allocation_gate
RIP: 0010:csd_lock_wait kernel/smp.c:229 [inline]
RIP: 0010:smp_call_function_single+0x289/0x510 kernel/smp.c:517
Code: 31 ff e8 fa ed 0a 00 41 83 e5 01 75 0a e8 3f ea 0a 00 e9 eb 00 00 00 f3 90 42 0f b6 04 23 84 c0 75 15 f7 44 24 48 01 00 00 00 <0f> 84 cd 00 00 00 e8 1c ea 0a 00 eb e0 44 89 f1 80 e1 07 80 c1 03
RSP: 0018:ffffc90001cff720 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff9200039feed RCX: ffff88811b5d62c0
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90001cff810 R08: ffffffff815fd236 R09: ffffed103ee2aec9
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000001 R14: ffffc90001cff768 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8ea3d8efa0 CR3: 000000000660f000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 smp_call_function_many_cond+0x94e/0xa30 kernel/smp.c:653
 smp_call_function_many kernel/smp.c:716 [inline]
 smp_call_function kernel/smp.c:738 [inline]
 on_each_cpu+0xa8/0x1a0 kernel/smp.c:837
 text_poke_sync arch/x86/kernel/alternative.c:1318 [inline]
 text_poke_bp_batch+0x47f/0x600 arch/x86/kernel/alternative.c:1562
 text_poke_flush arch/x86/kernel/alternative.c:1677 [inline]
 text_poke_finish+0x1a/0x30 arch/x86/kernel/alternative.c:1684
 arch_jump_label_transform_apply+0x15/0x30 arch/x86/kernel/jump_label.c:126
 __jump_label_update+0x36a/0x380 kernel/jump_label.c:459
 jump_label_update+0x379/0x400 kernel/jump_label.c:825
 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:624
 process_one_work+0x6dc/0xbd0 kernel/workqueue.c:2301
 worker_thread+0xaea/0x1510 kernel/workqueue.c:2447
 kthread+0x34b/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298
NMI backtrace for cpu 1
CPU: 1 PID: 7309 Comm: syz.3.913 Tainted: G             L    5.10.226-syzkaller-00444-g220ce693f83f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:preempt_count_sub+0x2b/0x160 kernel/sched/core.c:4486
Code: 48 89 e5 41 56 53 89 fb 48 c7 c0 00 e9 08 87 48 c1 e8 03 49 be 00 00 00 00 00 fc ff df 42 0f b6 04 30 84 c0 0f 85 c1 00 00 00 <83> 3d 7e c7 bf 05 00 75 22 65 8b 05 01 4c b9 7e 89 c1 81 e1 ff ff
RSP: 0018:ffffc90000170820 EFLAGS: 00000097
RAX: 0000000000000004 RBX: 0000000000000001 RCX: ffffffff8708e903
RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000001
RBP: ffffc90000170830 R08: dffffc0000000000 R09: ffffed10270acf11
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000046
R13: ffff888138567880 R14: dffffc0000000000 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa54b4ad58e CR3: 00000001059fb000 CR4: 00000000003506a0
DR0: 0000000000000008 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <NMI>
 </NMI>
 <IRQ>
 __raw_read_unlock_irqrestore include/linux/rwlock_api_smp.h:236 [inline]
 _raw_read_unlock_irqrestore+0x33/0x50 kernel/locking/spinlock.c:263
 send_sigio+0x1eb/0x230 fs/fcntl.c:810
 kill_fasync_rcu fs/fcntl.c:1014 [inline]
 kill_fasync+0x167/0x250 fs/fcntl.c:1028
 perf_event_wakeup kernel/events/core.c:6450 [inline]
 perf_pending_event+0x325/0x520 kernel/events/core.c:6506
 irq_work_single kernel/irq_work.c:148 [inline]
 irq_work_run_list+0x1c4/0x2c0 kernel/irq_work.c:170
 irq_work_run+0x69/0xf0 kernel/irq_work.c:179
 __sysvec_irq_work+0x66/0x1b0 arch/x86/kernel/irq_work.c:22
 run_sysvec_on_irqstack_cond arch/x86/include/asm/irq_stack.h:91 [inline]
 sysvec_irq_work+0xb7/0xd0 arch/x86/kernel/irq_work.c:17
 asm_sysvec_irq_work+0x12/0x20 arch/x86/include/asm/idtentry.h:661
RIP: 0010:__nlmsg_put+0xa1/0x1a0 net/netlink/af_netlink.c:2173
Code: 10 84 c0 0f 85 a1 00 00 00 44 89 3b 48 8d 7b 06 48 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 aa 00 00 00 8b 45 d4 66 89 43 06 <48> 8d 7b 0c 48 89 f8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 ab 00 00
RSP: 0018:ffffc90000170b18 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88812c4f9800 RCX: ffff888144e43b40
RDX: dffffc0000000000 RSI: 0000000000000080 RDI: ffff88812c4f9806
RBP: ffffc90000170b50 R08: ffffffff83bf7124 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000018
R13: 0000000000000055 R14: 0000000000000008 R15: 0000000000000018
 nlmsg_put include/net/netlink.h:920 [inline]
 nlmsg_populate_mdb_fill net/bridge/br_mdb.c:386 [inline]
 br_mdb_notify+0x599/0xca0 net/bridge/br_mdb.c:593
 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:lru_cache_disabled+0x0/0x40 mm/swap.c:971
Code: 3f d8 ff e8 f2 f2 ff ff 5d c3 55 48 89 e5 e8 57 3f d8 ff 31 ff e8 70 f4 ff ff 5d c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 <55> 48 89 e5 53 e8 36 3f d8 ff 48 c7 c7 80 f7 0b 87 be 04 00 00 00
RSP: 0018:ffffc900014a74d8 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888144e43b40
RDX: 0000000000000000 RSI: 00000000000001fe RDI: 0000000000000085
RBP: ffffc900014a7710 R08: ffffffff81a0b77e R09: fffff94000878417
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffea00043c2080 R14: ffff88813aeaed08 R15: 00007f0845da1000
 unmap_single_vma mm/memory.c:1551 [inline]
 unmap_vmas+0x37f/0x4f0 mm/memory.c:1583
 exit_mmap+0x2f2/0x5c0 mm/mmap.c:3355
 __mmput+0x95/0x2d0 kernel/fork.c:1153
 mmput+0x59/0x170 kernel/fork.c:1176
 exit_mm kernel/exit.c:539 [inline]
 do_exit+0xbda/0x2a50 kernel/exit.c:850
 do_group_exit+0x141/0x310 kernel/exit.c:985
 get_signal+0x10a0/0x1410 kernel/signal.c:2793
 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]
 syscall_exit_to_user_mode+0xa2/0x1a0 kernel/entry/common.c:274
 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f0846c1df19
Code: Unable to access opcode bytes at RIP 0x7f0846c1deef.
RSP: 002b:00007f0845274058 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: 0000000000000000 RBX: 00007f0846de4080 RCX: 00007f0846c1df19
RDX: 00000000200006c0 RSI: 0000000000005452 RDI: 0000000000000009
RBP: 00007f0846c91986 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f0846de4080 R15: 00007fff29077b08

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/05 23:19 android13-5.10-lts 220ce693f83f 29f61fce .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10-perf BUG: soft lockup in br_multicast_group_expired
* Struck through repros no longer work on HEAD.