====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc2-syzkaller-00266-g4b2b606075e5 #0 Not tainted ------------------------------------------------------ syz-executor.5/20981 is trying to acquire lock: ffff8880350aa5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880350aa5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_drop_all+0x3b/0x2f0 net/can/j1939/socket.c:139 but task is already holding lock: ffff8880360bd0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff8880360bd0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2c/0x160 net/can/j1939/socket.c:1276 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&priv->j1939_socks_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_errqueue+0xaa/0x1a0 net/can/j1939/socket.c:1083 j1939_session_destroy+0x276/0x4f0 net/can/j1939/transport.c:271 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put net/can/j1939/transport.c:299 [inline] j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_session_deactivate_locked+0x28c/0x330 net/can/j1939/transport.c:1074 j1939_cancel_active_session+0x183/0x360 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x19a/0x1d0 net/can/j1939/main.c:380 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8638 dev_change_flags+0x122/0x170 net/core/dev.c:8674 devinet_ioctl+0x13ef/0x1f00 net/ipv4/devinet.c:1167 inet_ioctl+0x3a6/0x3f0 net/ipv4/af_inet.c:990 sock_do_ioctl+0x113/0x270 net/socket.c:1220 sock_ioctl+0x229/0x6b0 net/socket.c:1339 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #1 (&priv->active_session_list_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x4b/0x4a0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x2bc/0x4d0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_session_completed+0xb7/0x170 net/can/j1939/transport.c:1222 j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1395 [inline] j1939_xtp_rx_eoma+0x293/0x600 net/can/j1939/transport.c:1410 j1939_tp_cmd_recv net/can/j1939/transport.c:2099 [inline] j1939_tp_recv+0x718/0xf50 net/can/j1939/transport.c:2144 j1939_can_recv+0x78b/0xa70 net/can/j1939/main.c:112 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x2a5/0x8e0 net/can/af_can.c:606 can_receive+0x31b/0x5c0 net/can/af_can.c:663 can_rcv+0x1dc/0x270 net/can/af_can.c:687 __netif_receive_skb_one_core+0x115/0x180 net/core/dev.c:5523 __netif_receive_skb+0x1f/0x1b0 net/core/dev.c:5637 process_backlog+0x101/0x6b0 net/core/dev.c:5965 __napi_poll.constprop.0+0xb4/0x530 net/core/dev.c:6527 napi_poll net/core/dev.c:6594 [inline] net_rx_action+0x956/0xe90 net/core/dev.c:6727 __do_softirq+0x218/0x965 kernel/softirq.c:553 do_softirq kernel/softirq.c:454 [inline] do_softirq+0xaa/0xe0 kernel/softirq.c:441 __local_bh_enable_ip+0xf8/0x120 kernel/softirq.c:381 spin_unlock_bh include/linux/spinlock.h:396 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] nsim_dev_trap_report_work+0x86a/0xc70 drivers/net/netdevsim/dev.c:850 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 -> #0 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_queue_drop_all+0x3b/0x2f0 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0x7f/0x160 net/can/j1939/socket.c:1282 j1939_netdev_notify+0x1a2/0x1d0 net/can/j1939/main.c:381 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8638 dev_change_flags+0x122/0x170 net/core/dev.c:8674 devinet_ioctl+0x13ef/0x1f00 net/ipv4/devinet.c:1167 inet_ioctl+0x3a6/0x3f0 net/ipv4/af_inet.c:990 sock_do_ioctl+0x113/0x270 net/socket.c:1220 sock_ioctl+0x229/0x6b0 net/socket.c:1339 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &jsk->sk_session_queue_lock --> &priv->active_session_list_lock --> &priv->j1939_socks_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->j1939_socks_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); lock(&jsk->sk_session_queue_lock); *** DEADLOCK *** 2 locks held by syz-executor.5/20981: #0: ffffffff8e6014e8 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x1d3/0x1f00 net/ipv4/devinet.c:1091 #1: ffff8880360bd0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff8880360bd0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2c/0x160 net/can/j1939/socket.c:1276 stack backtrace: CPU: 0 PID: 20981 Comm: syz-executor.5 Not tainted 6.6.0-rc2-syzkaller-00266-g4b2b606075e5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_queue_drop_all+0x3b/0x2f0 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0x7f/0x160 net/can/j1939/socket.c:1282 j1939_netdev_notify+0x1a2/0x1d0 net/can/j1939/main.c:381 notifier_call_chain+0xb6/0x3b0 kernel/notifier.c:93 call_netdevice_notifiers_info+0xb9/0x130 net/core/dev.c:1970 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline] call_netdevice_notifiers net/core/dev.c:2022 [inline] __dev_notify_flags+0x1f5/0x2e0 net/core/dev.c:8638 dev_change_flags+0x122/0x170 net/core/dev.c:8674 devinet_ioctl+0x13ef/0x1f00 net/ipv4/devinet.c:1167 inet_ioctl+0x3a6/0x3f0 net/ipv4/af_inet.c:990 sock_do_ioctl+0x113/0x270 net/socket.c:1220 sock_ioctl+0x229/0x6b0 net/socket.c:1339 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl fs/ioctl.c:857 [inline] __x64_sys_ioctl+0x18f/0x210 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f44c187cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f44c263c0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f44c199c050 RCX: 00007f44c187cae9 RDX: 0000000020000300 RSI: 0000000000008914 RDI: 0000000000000004 RBP: 00007f44c18c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f44c199c050 R15: 00007ffe1dc58b38