====================================================== WARNING: possible circular locking dependency detected 6.14.0-rc3-syzkaller-ge6747d19291c #0 Not tainted ------------------------------------------------------ syz.9.833/11874 is trying to acquire lock: ffff800092cc7618 (nr_neigh_list_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff800092cc7618 (nr_neigh_list_lock){+...}-{3:3}, at: nr_remove_neigh net/netrom/nr_route.c:307 [inline] ffff800092cc7618 (nr_neigh_list_lock){+...}-{3:3}, at: nr_dec_obs net/netrom/nr_route.c:472 [inline] ffff800092cc7618 (nr_neigh_list_lock){+...}-{3:3}, at: nr_rt_ioctl+0x308/0xdf4 net/netrom/nr_route.c:692 but task is already holding lock: ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_node_lock include/net/netrom.h:152 [inline] ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_dec_obs net/netrom/nr_route.c:459 [inline] ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_rt_ioctl+0x180/0xdf4 net/netrom/nr_route.c:692 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&nr_node->node_lock){+...}-{3:3}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x48/0x60 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] nr_node_lock include/net/netrom.h:152 [inline] nr_dec_obs net/netrom/nr_route.c:459 [inline] nr_rt_ioctl+0x180/0xdf4 net/netrom/nr_route.c:692 nr_ioctl+0x19c/0x474 net/netrom/af_netrom.c:1254 sock_do_ioctl+0x134/0x2d0 net/socket.c:1199 sock_ioctl+0x4ec/0x838 net/socket.c:1318 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #1 (nr_node_list_lock){+...}-{3:3}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x48/0x60 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] nr_rt_device_down+0xb8/0x6f8 net/netrom/nr_route.c:517 nr_device_event+0x138/0x164 net/netrom/af_netrom.c:126 notifier_call_chain+0x1c4/0x550 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info net/core/dev.c:2141 [inline] call_netdevice_notifiers_extack net/core/dev.c:2179 [inline] call_netdevice_notifiers net/core/dev.c:2193 [inline] dev_close_many+0x308/0x474 net/core/dev.c:1717 dev_close+0x174/0x250 net/core/dev.c:1739 bpq_device_event+0x318/0x830 drivers/net/hamradio/bpqether.c:547 notifier_call_chain+0x1c4/0x550 kernel/notifier.c:85 raw_notifier_call_chain+0x3c/0x50 kernel/notifier.c:453 call_netdevice_notifiers_info net/core/dev.c:2141 [inline] call_netdevice_notifiers_extack net/core/dev.c:2179 [inline] call_netdevice_notifiers net/core/dev.c:2193 [inline] dev_close_many+0x308/0x474 net/core/dev.c:1717 dev_close+0x174/0x250 net/core/dev.c:1739 bond_setup_by_slave+0x70/0x39c drivers/net/bonding/bond_main.c:1631 bond_enslave+0x620/0x2f0c drivers/net/bonding/bond_main.c:2043 bond_do_ioctl+0x270/0xde8 drivers/net/bonding/bond_main.c:4685 dev_ifsioc+0x748/0x9a0 dev_ioctl+0x4d8/0xd34 net/core/dev_ioctl.c:826 sock_do_ioctl+0x1d4/0x2d0 net/socket.c:1213 sock_ioctl+0x4ec/0x838 net/socket.c:1318 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 -> #0 (nr_neigh_list_lock){+...}-{3:3}: check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x34f0/0x7904 kernel/locking/lockdep.c:5228 lock_acquire+0x23c/0x724 kernel/locking/lockdep.c:5851 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x48/0x60 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] nr_remove_neigh net/netrom/nr_route.c:307 [inline] nr_dec_obs net/netrom/nr_route.c:472 [inline] nr_rt_ioctl+0x308/0xdf4 net/netrom/nr_route.c:692 nr_ioctl+0x19c/0x474 net/netrom/af_netrom.c:1254 sock_do_ioctl+0x134/0x2d0 net/socket.c:1199 sock_ioctl+0x4ec/0x838 net/socket.c:1318 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 other info that might help us debug this: Chain exists of: nr_neigh_list_lock --> nr_node_list_lock --> &nr_node->node_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&nr_node->node_lock); lock(nr_node_list_lock); lock(&nr_node->node_lock); lock(nr_neigh_list_lock); *** DEADLOCK *** 2 locks held by syz.9.833/11874: #0: ffff800092cc7678 (nr_node_list_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #0: ffff800092cc7678 (nr_node_list_lock){+...}-{3:3}, at: nr_dec_obs net/netrom/nr_route.c:457 [inline] #0: ffff800092cc7678 (nr_node_list_lock){+...}-{3:3}, at: nr_rt_ioctl+0x104/0xdf4 net/netrom/nr_route.c:692 #1: ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_node_lock include/net/netrom.h:152 [inline] #1: ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_dec_obs net/netrom/nr_route.c:459 [inline] #1: ffff0000ef2f8370 (&nr_node->node_lock){+...}-{3:3}, at: nr_rt_ioctl+0x180/0xdf4 net/netrom/nr_route.c:692 stack backtrace: CPU: 1 UID: 0 PID: 11874 Comm: syz.9.833 Not tainted 6.14.0-rc3-syzkaller-ge6747d19291c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call trace: show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C) __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0xe4/0x150 lib/dump_stack.c:120 dump_stack+0x1c/0x28 lib/dump_stack.c:129 print_circular_bug+0x154/0x1c0 kernel/locking/lockdep.c:2076 check_noncircular+0x310/0x404 kernel/locking/lockdep.c:2208 check_prev_add kernel/locking/lockdep.c:3163 [inline] check_prevs_add kernel/locking/lockdep.c:3282 [inline] validate_chain kernel/locking/lockdep.c:3906 [inline] __lock_acquire+0x34f0/0x7904 kernel/locking/lockdep.c:5228 lock_acquire+0x23c/0x724 kernel/locking/lockdep.c:5851 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x48/0x60 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] nr_remove_neigh net/netrom/nr_route.c:307 [inline] nr_dec_obs net/netrom/nr_route.c:472 [inline] nr_rt_ioctl+0x308/0xdf4 net/netrom/nr_route.c:692 nr_ioctl+0x19c/0x474 net/netrom/af_netrom.c:1254 sock_do_ioctl+0x134/0x2d0 net/socket.c:1199 sock_ioctl+0x4ec/0x838 net/socket.c:1318 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl fs/ioctl.c:892 [inline] __arm64_sys_ioctl+0x14c/0x1cc fs/ioctl.c:892 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600