vxcan0: j1939_tp_rxtimer: 0xffff88808c4cb800: rx timeout, send abort ====================================================== WARNING: possible circular locking dependency detected 6.2.0-rc1-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/3393 is trying to acquire lock: ffff88807b9510d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88807b9510d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 but task is already holding lock: ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 (&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:355 [inline] j1939_session_list_lock net/can/j1939/transport.c:238 [inline] j1939_session_activate+0x47/0x4b0 net/can/j1939/transport.c:1561 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x1b6/0x450 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1109 [inline] j1939_session_completed+0x19a/0x1f0 net/can/j1939/transport.c:1222 j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1392 [inline] j1939_xtp_rx_eoma+0x2a1/0x5e0 net/can/j1939/transport.c:1407 j1939_tp_cmd_recv net/can/j1939/transport.c:2096 [inline] j1939_tp_recv+0x71c/0xcd0 net/can/j1939/transport.c:2141 j1939_can_recv net/can/j1939/main.c:112 [inline] j1939_can_recv+0x78e/0xa30 net/can/j1939/main.c:38 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x5d4/0x8d0 net/can/af_can.c:606 can_receive+0x31d/0x580 net/can/af_can.c:663 can_rcv+0x1e1/0x230 net/can/af_can.c:687 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5482 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5596 process_backlog+0x3e4/0x810 net/core/dev.c:5924 __napi_poll+0xb8/0x770 net/core/dev.c:6485 napi_poll net/core/dev.c:6552 [inline] net_rx_action+0xa00/0xde0 net/core/dev.c:6663 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 run_ksoftirqd kernel/softirq.c:934 [inline] run_ksoftirqd+0x31/0x60 kernel/softirq.c:926 smpboot_thread_fn+0x659/0xa20 kernel/smpboot.c:164 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 -> #1 (&jsk->sk_session_queue_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:355 [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:1275 j1939_netdev_notify+0x19d/0x1d0 net/can/j1939/main.c:379 notifier_call_chain+0xb5/0x200 kernel/notifier.c:87 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1944 call_netdevice_notifiers_extack net/core/dev.c:1982 [inline] call_netdevice_notifiers net/core/dev.c:1996 [inline] __dev_notify_flags+0x1ea/0x2d0 net/core/dev.c:8571 dev_change_flags+0x11b/0x170 net/core/dev.c:8607 do_setlink+0x9f1/0x3bb0 net/core/rtnetlink.c:2827 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3590 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3637 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd -> #0 (&priv->j1939_socks_lock){+.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __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:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 rcu_rnp_online_cpus kernel/rcu/tree.c:225 [inline] rcu_rdp_cpu_online kernel/rcu/tree.c:235 [inline] rcu_lockdep_current_cpu_online kernel/rcu/tree.c:768 [inline] rcu_lockdep_current_cpu_online+0xc9/0x140 kernel/rcu/tree.c:752 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x5cf/0x810 kernel/locking/lockdep.c:5679 rcu_lock_release include/linux/rcupdate.h:330 [inline] rcu_read_unlock include/linux/rcupdate.h:797 [inline] inet_twsk_purge+0x562/0x8a0 net/ipv4/inet_timewait_sock.c:312 ops_exit_list+0x125/0x170 net/core/net_namespace.c:174 setup_net+0x9bd/0xe60 net/core/net_namespace.c:356 copy_net_ns+0x31b/0x6b0 net/core/net_namespace.c:483 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x3b3/0x4a0 kernel/nsproxy.c:179 copy_process+0x30d3/0x7520 kernel/fork.c:2269 kernel_clone+0xeb/0x990 kernel/fork.c:2681 __do_sys_clone3+0x1cd/0x2e0 kernel/fork.c:2980 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &priv->j1939_socks_lock --> &jsk->sk_session_queue_lock --> &priv->active_session_list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&priv->active_session_list_lock); lock(&jsk->sk_session_queue_lock); lock(&priv->active_session_list_lock); lock(&priv->j1939_socks_lock); *** DEADLOCK *** 3 locks held by syz-executor.0/3393: #0: ffffffff8e0a9f50 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x2f8/0x6b0 net/core/net_namespace.c:479 #1: ffffffff8c7917c0 (rcu_read_lock){....}-{1:2}, at: inet_twsk_purge+0xeb/0x8a0 net/ipv4/inet_timewait_sock.c:276 #2: ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #2: ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #2: ffff88807b951088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe9/0x220 net/can/j1939/transport.c:1248 stack backtrace: CPU: 0 PID: 3393 Comm: syz-executor.0 Not tainted 6.2.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2177 check_prev_add kernel/locking/lockdep.c:3097 [inline] check_prevs_add kernel/locking/lockdep.c:3216 [inline] validate_chain kernel/locking/lockdep.c:3831 [inline] __lock_acquire+0x2a43/0x56d0 kernel/locking/lockdep.c:5055 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __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:355 [inline] j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 __j1939_session_cancel+0x3b9/0x460 net/can/j1939/transport.c:1132 j1939_tp_rxtimer.cold+0x1f6/0x24f net/can/j1939/transport.c:1257 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0xfb0 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x1fb/0xadc kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x123/0x180 kernel/softirq.c:650 irq_exit_rcu+0x9/0x20 kernel/softirq.c:662 sysvec_apic_timer_interrupt+0x97/0xc0 arch/x86/kernel/apic/apic.c:1107 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:225 [inline] RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:235 [inline] RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:768 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0xc9/0x140 kernel/rcu/tree.c:752 Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 75 72 48 b8 00 00 00 00 00 fc ff df 48 8b 5b 18 48 8d 7b 70 48 89 fa 48 c1 ea 03 80 3c 02 00 <75> 5a 48 8b 53 70 b8 01 00 00 00 48 85 d5 74 0c 65 ff 0d 78 7b 98 RSP: 0018:ffffc90004f37718 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffffff8c79bd00 RCX: ffffffff8163f019 RDX: 1ffffffff18f37ae RSI: 0000000000000002 RDI: ffffffff8c79bd70 RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8e72d397 R10: fffffbfff1ce5a72 R11: 1ffffffff18f37b9 R12: 0000000000000001 R13: ffffc90004f37990 R14: 0000000000000000 R15: 00000000000589b7 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x29/0x70 kernel/rcu/update.c:123 trace_lock_release include/trace/events/lock.h:69 [inline] lock_release+0x5cf/0x810 kernel/locking/lockdep.c:5679 rcu_lock_release include/linux/rcupdate.h:330 [inline] rcu_read_unlock include/linux/rcupdate.h:797 [inline] inet_twsk_purge+0x562/0x8a0 net/ipv4/inet_timewait_sock.c:312 ops_exit_list+0x125/0x170 net/core/net_namespace.c:174 setup_net+0x9bd/0xe60 net/core/net_namespace.c:356 copy_net_ns+0x31b/0x6b0 net/core/net_namespace.c:483 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110 copy_namespaces+0x3b3/0x4a0 kernel/nsproxy.c:179 copy_process+0x30d3/0x7520 kernel/fork.c:2269 kernel_clone+0xeb/0x990 kernel/fork.c:2681 __do_sys_clone3+0x1cd/0x2e0 kernel/fork.c:2980 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f34cd28c0a9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f34cdf74038 EFLAGS: 00000246 ORIG_RAX: 00000000000001b3 RAX: ffffffffffffffda RBX: 00007f34cd3abf80 RCX: 00007f34cd28c0a9 RDX: 0000000000000000 RSI: 0000000000000058 RDI: 00007f34cdf74050 RBP: 00007f34cd2e7ae9 R08: 0000000000000000 R09: 0000000000000058 R10: 00007f34cdf74050 R11: 0000000000000246 R12: 0000000000000058 R13: 00007f34cd4cfb1f R14: 00007f34cdf74300 R15: 0000000000022000 vxcan0: j1939_tp_rxtimer: 0xffff88808c4cb800: abort rx timeout. Force session deactivation ---------------- Code disassembly (best guess): 0: 48 89 fa mov %rdi,%rdx 3: 48 c1 ea 03 shr $0x3,%rdx 7: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) b: 75 72 jne 0x7f d: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 14: fc ff df 17: 48 8b 5b 18 mov 0x18(%rbx),%rbx 1b: 48 8d 7b 70 lea 0x70(%rbx),%rdi 1f: 48 89 fa mov %rdi,%rdx 22: 48 c1 ea 03 shr $0x3,%rdx 26: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) * 2a: 75 5a jne 0x86 <-- trapping instruction 2c: 48 8b 53 70 mov 0x70(%rbx),%rdx 30: b8 01 00 00 00 mov $0x1,%eax 35: 48 85 d5 test %rdx,%rbp 38: 74 0c je 0x46 3a: 65 gs 3b: ff .byte 0xff 3c: 0d .byte 0xd 3d: 78 7b js 0xba 3f: 98 cwtl