============================================ WARNING: possible recursive locking detected 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 Not tainted -------------------------------------------- dhcpcd-run-hook/8964 is trying to acquire lock: ffff888059d7af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888059d7af30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 but task is already holding lock: ffff88807fadcf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88807fadcf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 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 12 locks held by dhcpcd-run-hook/8964: #0: ffff8880305881e0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:146 [inline] #0: ffff8880305881e0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1bd/0x4c0 mm/util.c:577 #1: ffff88802295ea18 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: i_mmap_lock_write include/linux/fs.h:545 [inline] #1: ffff88802295ea18 (&mapping->i_mmap_rwsem){++++}-{4:4}, at: vma_prepare+0x12f/0x4b0 mm/vma.c:264 #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: is_bpf_text_address+0x26/0x2b0 kernel/bpf/core.c:772 #3: ffffc90000007be0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbe/0x5f0 kernel/time/timer.c:1786 #4: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #4: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #4: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: ndisc_send_skb+0x208/0x1400 net/ipv6/ndisc.c:484 #5: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #5: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: ip6_finish_output2+0x701/0x16a0 net/ipv6/ip6_output.c:126 #6: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #6: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #6: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4554 #7: ffff88807fadcf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #7: ffff88807fadcf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 #8: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #8: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #8: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0x9e/0x2860 net/hsr/hsr_forward.c:728 #9: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #9: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #9: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4554 #10: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #10: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #10: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x185/0x1840 net/bridge/br_device.c:52 #11: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #11: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #11: ffffffff8df3dd40 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4554 stack backtrace: CPU: 0 UID: 0 PID: 8964 Comm: dhcpcd-run-hook Not tainted 6.15.0-rc6-syzkaller-00278-g172a9d94339c #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_deadlock_bug+0x28b/0x2a0 kernel/locking/lockdep.c:3042 check_deadlock kernel/locking/lockdep.c:3094 [inline] validate_chain+0x1a3f/0x2140 kernel/locking/lockdep.c:3896 __lock_acquire+0xaac/0xd20 kernel/locking/lockdep.c:5235 lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x36/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 __netdev_start_xmit include/linux/netdevice.h:5204 [inline] netdev_start_xmit include/linux/netdevice.h:5213 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x302/0x880 net/core/dev.c:3792 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4629 dev_queue_xmit include/linux/netdevice.h:3350 [inline] br_dev_queue_push_xmit+0x6c5/0x890 net/bridge/br_forward.c:53 NF_HOOK+0x31d/0x3c0 include/linux/netfilter.h:314 br_forward_finish+0xd3/0x130 net/bridge/br_forward.c:66 NF_HOOK+0x31d/0x3c0 include/linux/netfilter.h:314 __br_forward+0x41e/0x600 net/bridge/br_forward.c:115 deliver_clone net/bridge/br_forward.c:131 [inline] maybe_deliver+0xb5/0x160 net/bridge/br_forward.c:190 br_flood+0x31a/0x6a0 net/bridge/br_forward.c:237 br_dev_xmit+0x11b3/0x1840 net/bridge/br_device.c:108 __netdev_start_xmit include/linux/netdevice.h:5204 [inline] netdev_start_xmit include/linux/netdevice.h:5213 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x302/0x880 net/core/dev.c:3792 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4629 dev_queue_xmit include/linux/netdevice.h:3350 [inline] hsr_xmit net/hsr/hsr_forward.c:430 [inline] hsr_forward_do net/hsr/hsr_forward.c:571 [inline] hsr_forward_skb+0x158b/0x2860 net/hsr/hsr_forward.c:733 hsr_dev_xmit+0x1a5/0x220 net/hsr/hsr_device.c:235 __netdev_start_xmit include/linux/netdevice.h:5204 [inline] netdev_start_xmit include/linux/netdevice.h:5213 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x302/0x880 net/core/dev.c:3792 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4629 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x11fe/0x16a0 net/ipv6/ip6_output.c:141 __ip6_finish_output net/ipv6/ip6_output.c:-1 [inline] ip6_finish_output+0x234/0x7d0 net/ipv6/ip6_output.c:226 NF_HOOK include/linux/netfilter.h:314 [inline] ndisc_send_skb+0xb47/0x1400 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x369/0x670 net/ipv6/addrconf.c:4041 call_timer_fn+0x17e/0x5f0 kernel/time/timer.c:1789 expire_timers kernel/time/timer.c:1840 [inline] __run_timers kernel/time/timer.c:2414 [inline] __run_timer_base+0x61a/0x860 kernel/time/timer.c:2426 run_timer_base kernel/time/timer.c:2435 [inline] run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2445 handle_softirqs+0x283/0x870 kernel/softirq.c:579 __do_softirq kernel/softirq.c:613 [inline] invoke_softirq kernel/softirq.c:453 [inline] __irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696 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:__lt_find include/linux/rbtree_latch.h:-1 [inline] RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:210 [inline] RIP: 0010:bpf_ksym_find kernel/bpf/core.c:740 [inline] RIP: 0010:is_bpf_text_address+0xf0/0x2b0 kernel/bpf/core.c:773 Code: bd 00 00 00 00 00 fc ff df 44 8b 25 da 58 f2 0b 44 89 e3 83 e3 01 4c 8d 3c dd f0 13 c1 8d 4c 89 f8 48 c1 e8 03 42 80 3c 28 00 <74> 08 4c 89 ff e8 36 30 53 00 4d 8b 3f 4d 85 ff 0f 84 c1 00 00 00 RSP: 0018:ffffc9000380e7f0 EFLAGS: 00000246 RAX: 1ffffffff1b8227e RBX: 0000000000000000 RCX: ffff88802e8fda00 RDX: 0000000000000000 RSI: ffffffff8bc1f320 RDI: ffffffff8bc1f2e0 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff81ceba36 R12: 0000000000000004 R13: dffffc0000000000 R14: 00007f29f31df242 R15: ffffffff8dc113f0 kernel_text_address+0xa5/0xe0 kernel/extable.c:125 __kernel_text_address+0xd/0x40 kernel/extable.c:79 unwind_get_return_address+0x4d/0x90 arch/x86/kernel/unwind_orc.c:369 arch_stack_walk+0xfc/0x150 arch/x86/kernel/stacktrace.c:26 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47 kasan_record_aux_stack+0xbc/0xd0 mm/kasan/generic.c:548 __call_rcu_common kernel/rcu/tree.c:3082 [inline] call_rcu+0x142/0x990 kernel/rcu/tree.c:3202 mas_wr_node_store lib/maple_tree.c:3863 [inline] mas_wr_store_entry+0x1eaf/0x2550 lib/maple_tree.c:4083 mas_store_prealloc+0xb02/0xf60 lib/maple_tree.c:5475 vma_iter_store_new mm/vma.h:455 [inline] vma_complete+0x224/0xa90 mm/vma.c:323 __split_vma+0x84f/0x9b0 mm/vma.c:523 vms_gather_munmap_vmas+0x4ab/0x12b0 mm/vma.c:1336 __mmap_prepare mm/vma.c:2303 [inline] __mmap_region mm/vma.c:2506 [inline] mmap_region+0x5f5/0x1e50 mm/vma.c:2597 do_mmap+0xc68/0x1100 mm/mmap.c:561 vm_mmap_pgoff+0x31b/0x4c0 mm/util.c:579 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:607 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f29f31df242 Code: 08 00 04 00 00 eb e2 90 41 f7 c1 ff 0f 00 00 75 27 55 89 cd 53 48 89 fb 48 85 ff 74 33 41 89 ea 48 89 df b8 09 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5e 5b 5d c3 0f 1f 00 c7 05 46 40 01 00 16 00 RSP: 002b:00007ffeaa60af18 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f29f2eb1000 RCX: 00007f29f31df242 RDX: 0000000000000001 RSI: 0000000000002000 RDI: 00007f29f2eb1000 RBP: 0000000000000812 R08: 0000000000000003 R09: 0000000000005000 R10: 0000000000000812 R11: 0000000000000206 R12: 00007ffeaa60afa0 R13: 00007f29f2eb60c0 R14: 00007ffeaa60b350 R15: 00000fffd54c15e6 ---------------- Code disassembly (best guess): 0: bd 00 00 00 00 mov $0x0,%ebp 5: 00 fc add %bh,%ah 7: ff (bad) 8: df 44 8b 25 filds 0x25(%rbx,%rcx,4) c: da 58 f2 ficompl -0xe(%rax) f: 0b 44 89 e3 or -0x1d(%rcx,%rcx,4),%eax 13: 83 e3 01 and $0x1,%ebx 16: 4c 8d 3c dd f0 13 c1 lea -0x723eec10(,%rbx,8),%r15 1d: 8d 1e: 4c 89 f8 mov %r15,%rax 21: 48 c1 e8 03 shr $0x3,%rax 25: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) * 2a: 74 08 je 0x34 <-- trapping instruction 2c: 4c 89 ff mov %r15,%rdi 2f: e8 36 30 53 00 call 0x53306a 34: 4d 8b 3f mov (%r15),%r15 37: 4d 85 ff test %r15,%r15 3a: 0f 84 c1 00 00 00 je 0x101