============================================ WARNING: possible recursive locking detected 6.15.0-rc4-syzkaller-00808-ga7371be8c8f5 #0 Not tainted -------------------------------------------- syz.1.1002/9453 is trying to acquire lock: ffff88805cf66f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88805cf66f30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 but task is already holding lock: ffff88805825cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88805825cf30 (&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 syz.1.1002/9453: #0: ffff888059a73208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline] #0: ffff888059a73208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline] #0: ffff888059a73208 (&sb->s_type->i_mutex_key#11){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391 #1: ffff888058186258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline] #1: ffff888058186258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_release+0x798/0xce0 net/packet/af_packet.c:3203 #2: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #2: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #2: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1155 [inline] #2: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0xa5/0x2390 arch/x86/kernel/unwind_orc.c:479 #3: ffffc90000007be0 ((&ndev->rs_timer)){+.-.}-{0:0}, at: call_timer_fn+0xbe/0x5f0 kernel/time/timer.c:1786 #4: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #4: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #4: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: ndisc_send_skb+0x208/0x1400 net/ipv6/ndisc.c:484 #5: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #5: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #5: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: ip6_finish_output2+0x701/0x16a0 net/ipv6/ip6_output.c:126 #6: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #6: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #6: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4606 #7: ffff88805825cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #7: ffff88805825cf30 (&hsr->seqnr_lock){+.-.}-{3:3}, at: hsr_dev_xmit+0x19a/0x220 net/hsr/hsr_device.c:234 #8: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #8: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #8: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: hsr_forward_skb+0x9e/0x2860 net/hsr/hsr_forward.c:728 #9: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #9: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #9: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4606 #10: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #10: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #10: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: br_dev_xmit+0x185/0x1840 net/bridge/br_device.c:52 #11: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: local_bh_disable include/linux/bottom_half.h:20 [inline] #11: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: rcu_read_lock_bh include/linux/rcupdate.h:892 [inline] #11: ffffffff8df3b8c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit+0x27e/0x3a70 net/core/dev.c:4606 stack backtrace: CPU: 0 UID: 0 PID: 9453 Comm: syz.1.1002 Not tainted 6.15.0-rc4-syzkaller-00808-ga7371be8c8f5 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025 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:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3828 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3844 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4681 dev_queue_xmit include/linux/netdevice.h:3349 [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:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3828 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3844 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4681 dev_queue_xmit include/linux/netdevice.h:3349 [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:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3828 [inline] dev_hard_start_xmit+0x2d4/0x830 net/core/dev.c:3844 __dev_queue_xmit+0x1adf/0x3a70 net/core/dev.c:4681 neigh_output include/net/neighbour.h:539 [inline] ip6_finish_output2+0x11fb/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:4038 call_timer_fn+0x17b/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:on_stack arch/x86/include/asm/stacktrace.h:55 [inline] RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline] RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline] RIP: 0010:unwind_next_frame+0xabc/0x2390 arch/x86/kernel/unwind_orc.c:585 Code: 76 01 83 e6 07 83 fe 04 4c 89 64 24 10 0f 84 49 04 00 00 83 fe 03 0f 84 f3 01 00 00 83 fe 02 0f 85 a1 07 00 00 4c 89 7c 24 28 <4d> 8d 7e 08 4c 89 fd 48 c1 ed 03 48 b8 00 00 00 00 00 fc ff df 80 RSP: 0018:ffffc9001af17618 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffffffff909fa905 RCX: ffffffff8ff42020 RDX: ffffffff909fa900 RSI: 0000000000000002 RDI: ffffffff8bc1cfc0 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: ffffffff817199f5 R12: ffffc9001af17d28 R13: ffffc9001af17738 R14: ffffc9001af176e8 R15: 1ffffffff213f520 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 save_stack+0xf7/0x1f0 mm/page_owner.c:156 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:308 reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1258 [inline] __free_frozen_pages+0xb14/0xce0 mm/page_alloc.c:2721 free_pg_vec net/packet/af_packet.c:4396 [inline] packet_set_ring+0x1899/0x2380 net/packet/af_packet.c:4615 packet_release+0x83e/0xce0 net/packet/af_packet.c:3211 __sock_release net/socket.c:647 [inline] sock_close+0xc0/0x240 net/socket.c:1391 __fput+0x449/0xa70 fs/file_table.c:465 task_work_run+0x1d1/0x260 kernel/task_work.c:227 resume_user_mode_work+0x5e/0x80 include/linux/resume_user_mode.h:50 exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x9a/0x120 kernel/entry/common.c:218 do_syscall_64+0x103/0x210 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f919998e969 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd866cb6b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007f9199bb7ba0 RCX: 00007f919998e969 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00007f9199bb7ba0 R08: 0000000000000200 R09: 0000001d866cb9af R10: 00000000003ffbdc R11: 0000000000000246 R12: 000000000004d9b8 R13: 00007f9199bb6160 R14: ffffffffffffffff R15: 00007ffd866cb7d0 ---------------- Code disassembly (best guess): 0: 76 01 jbe 0x3 2: 83 e6 07 and $0x7,%esi 5: 83 fe 04 cmp $0x4,%esi 8: 4c 89 64 24 10 mov %r12,0x10(%rsp) d: 0f 84 49 04 00 00 je 0x45c 13: 83 fe 03 cmp $0x3,%esi 16: 0f 84 f3 01 00 00 je 0x20f 1c: 83 fe 02 cmp $0x2,%esi 1f: 0f 85 a1 07 00 00 jne 0x7c6 25: 4c 89 7c 24 28 mov %r15,0x28(%rsp) * 2a: 4d 8d 7e 08 lea 0x8(%r14),%r15 <-- trapping instruction 2e: 4c 89 fd mov %r15,%rbp 31: 48 c1 ed 03 shr $0x3,%rbp 35: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 3c: fc ff df 3f: 80 .byte 0x80