============================================ WARNING: possible recursive locking detected 6.12.0-rc5-syzkaller-01142-gecf99864ea6b #0 Not tainted -------------------------------------------- kworker/1:5/5898 is trying to acquire lock: ffff88806315ef30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88806315ef30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: hsr_dev_xmit+0x13e/0x1d0 net/hsr/hsr_device.c:234 but task is already holding lock: ffff888029810f30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888029810f30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x27c/0xcc0 net/hsr/hsr_device.c:317 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&hsr->seqnr_lock); lock(&hsr->seqnr_lock); *** DEADLOCK *** May be due to missing lock nesting notation 10 locks held by kworker/1:5/5898: #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3204 [inline] #0: ffff88801ac80948 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x93b/0x1850 kernel/workqueue.c:3310 #1: ffffc9000462fd00 ((work_completion)(&w->work)#2){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3205 [inline] #1: ffffc9000462fd00 ((work_completion)(&w->work)#2){+.+.}-{0:0}, at: process_scheduled_works+0x976/0x1850 kernel/workqueue.c:3310 #2: ffffffff8fd46788 (nf_conntrack_mutex){+.+.}-{3:3}, at: nf_ct_iterate_cleanup+0x41/0x4f0 net/netfilter/nf_conntrack_core.c:2364 #3: ffffc90000a18c00 ((&hsr->announce_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1791 #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #4: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: hsr_announce+0xaa/0x3a0 net/hsr/hsr_device.c:406 #5: ffff888029810f30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #5: ffff888029810f30 (&hsr->seqnr_lock){+.-.}-{2:2}, at: send_hsr_supervision_frame+0x27c/0xcc0 net/hsr/hsr_device.c:317 #6: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #6: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #6: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: hsr_forward_skb+0xaf/0x2b90 net/hsr/hsr_forward.c:714 #7: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #7: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:901 [inline] #7: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2da/0x3f30 net/core/dev.c:4359 #8: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #8: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #8: ffffffff8e937da0 (rcu_read_lock){....}-{1:2}, at: br_dev_xmit+0x21d/0x1b10 net/bridge/br_device.c:50 #9: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #9: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:901 [inline] #9: ffffffff8e937e00 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2da/0x3f30 net/core/dev.c:4359 stack backtrace: CPU: 1 UID: 0 PID: 5898 Comm: kworker/1:5 Not tainted 6.12.0-rc5-syzkaller-01142-gecf99864ea6b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events iterate_cleanup_work Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_deadlock_bug+0x483/0x620 kernel/locking/lockdep.c:3037 check_deadlock kernel/locking/lockdep.c:3089 [inline] validate_chain+0x15e2/0x5920 kernel/locking/lockdep.c:3891 __lock_acquire+0x1384/0x2050 kernel/locking/lockdep.c:5202 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5825 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] hsr_dev_xmit+0x13e/0x1d0 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:4985 [inline] netdev_start_xmit include/linux/netdevice.h:4994 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3606 __dev_queue_xmit+0x1b56/0x3f30 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3151 [inline] br_dev_queue_push_xmit+0x703/0x8d0 net/bridge/br_forward.c:53 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 br_forward_finish+0xd8/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x3a7/0x460 include/linux/netfilter.h:314 __br_forward+0x489/0x660 net/bridge/br_forward.c:115 br_dev_xmit+0x11fc/0x1b10 __netdev_start_xmit include/linux/netdevice.h:4985 [inline] netdev_start_xmit include/linux/netdevice.h:4994 [inline] xmit_one net/core/dev.c:3590 [inline] dev_hard_start_xmit+0x27a/0x7e0 net/core/dev.c:3606 __dev_queue_xmit+0x1b56/0x3f30 net/core/dev.c:4434 dev_queue_xmit include/linux/netdevice.h:3151 [inline] hsr_xmit net/hsr/hsr_forward.c:418 [inline] hsr_forward_do net/hsr/hsr_forward.c:559 [inline] hsr_forward_skb+0x17d7/0x2b90 net/hsr/hsr_forward.c:719 send_hsr_supervision_frame+0x63b/0xcc0 net/hsr/hsr_device.c:351 hsr_announce+0x1f8/0x3a0 net/hsr/hsr_device.c:408 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1794 expire_timers kernel/time/timer.c:1845 [inline] __run_timers kernel/time/timer.c:2419 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2430 run_timer_base kernel/time/timer.c:2439 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2449 handle_softirqs+0x2c5/0x980 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210 Code: 89 fb e8 23 00 00 00 48 8b 3d 34 f8 9c 0c 48 89 de 5b e9 73 d6 5d 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 c0 d5 03 00 65 8b 15 90 fb RSP: 0018:ffffc9000462fa90 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff888031093c00 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff88802450e800 R08: ffffffff89df23c0 R09: 1ffffffff285a911 R10: dffffc0000000000 R11: fffffbfff285a912 R12: ffffc9000462fb20 R13: 1ffff110048a1d00 R14: dffffc0000000000 R15: ffffc9000462fb28 get_next_corpse net/netfilter/nf_conntrack_core.c:2314 [inline] nf_ct_iterate_cleanup+0x4a9/0x4f0 net/netfilter/nf_conntrack_core.c:2365 iterate_cleanup_work+0x146/0x260 net/netfilter/nf_nat_masquerade.c:87 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 IPVS: lblc: UDP 224.0.0.2:0 - no destination available ---------------- Code disassembly (best guess): 0: 89 fb mov %edi,%ebx 2: e8 23 00 00 00 call 0x2a 7: 48 8b 3d 34 f8 9c 0c mov 0xc9cf834(%rip),%rdi # 0xc9cf842 e: 48 89 de mov %rbx,%rsi 11: 5b pop %rbx 12: e9 73 d6 5d 00 jmp 0x5dd68a 17: 0f 1f 00 nopl (%rax) 1a: 90 nop 1b: 90 nop 1c: 90 nop 1d: 90 nop 1e: 90 nop 1f: 90 nop 20: 90 nop 21: 90 nop 22: 90 nop 23: 90 nop 24: 90 nop 25: 90 nop 26: 90 nop 27: 90 nop 28: 90 nop 29: 90 nop * 2a: f3 0f 1e fa endbr64 <-- trapping instruction 2e: 48 8b 04 24 mov (%rsp),%rax 32: 65 48 8b 0c 25 c0 d5 mov %gs:0x3d5c0,%rcx 39: 03 00 3b: 65 gs 3c: 8b .byte 0x8b 3d: 15 .byte 0x15 3e: 90 nop 3f: fb sti