vxcan0: j1939_tp_rxtimer: 0xffff888027689800: rx timeout, send abort ====================================================== WARNING: possible circular locking dependency detected 6.2.0-syzkaller-13467-g0988a0ea7919 #0 Not tainted ------------------------------------------------------ syz-executor.1/11135 is trying to acquire lock: ffff88802efb90d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88802efb90d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 but task is already holding lock: ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe4/0x4b0 net/can/j1939/transport.c:1244 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:1557 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x2bf/0x4d0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1105 [inline] j1939_session_completed+0xb6/0x170 net/can/j1939/transport.c:1218 j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1388 [inline] j1939_xtp_rx_eoma+0x2a1/0x680 net/can/j1939/transport.c:1403 j1939_tp_cmd_recv net/can/j1939/transport.c:2092 [inline] j1939_tp_recv+0x71e/0xf50 net/can/j1939/transport.c:2137 j1939_can_recv net/can/j1939/main.c:112 [inline] j1939_can_recv+0x78e/0xa80 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/0x5c0 net/can/af_can.c:663 can_rcv+0x1e1/0x280 net/can/af_can.c:687 __netif_receive_skb_one_core+0x114/0x180 net/core/dev.c:5479 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5593 process_backlog+0x279/0x850 net/core/dev.c:5921 __napi_poll+0xb8/0x870 net/core/dev.c:6482 napi_poll net/core/dev.c:6549 [inline] net_rx_action+0x9fd/0xdc0 net/core/dev.c:6659 __do_softirq+0x2e3/0xae3 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:1937 call_netdevice_notifiers_extack net/core/dev.c:1975 [inline] call_netdevice_notifiers net/core/dev.c:1989 [inline] __dev_notify_flags+0x1ea/0x2d0 net/core/dev.c:8568 dev_change_flags+0x11b/0x170 net/core/dev.c:8604 do_setlink+0x9f4/0x3d30 net/core/rtnetlink.c:2833 __rtnl_newlink+0xd69/0x1840 net/core/rtnetlink.c:3623 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3670 rtnetlink_rcv_msg+0x43d/0xd50 net/core/rtnetlink.c:6174 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2574 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 ____sys_sendmsg+0x71c/0x900 net/socket.c:2504 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2558 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2587 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:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056 lock_acquire kernel/locking/lockdep.c:5669 [inline] lock_acquire+0x1e3/0x670 kernel/locking/lockdep.c:5634 __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:1128 j1939_tp_rxtimer+0x3df/0x4b0 net/can/j1939/transport.c:1253 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0x1010 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x2e3/0xae3 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 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:645 rcu_rnp_online_cpus kernel/rcu/tree.c:4038 [inline] rcu_rdp_cpu_online kernel/rcu/tree.c:4048 [inline] rcu_lockdep_current_cpu_online kernel/rcu/tree.c:4082 [inline] rcu_lockdep_current_cpu_online+0xc9/0x140 kernel/rcu/tree.c:4066 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_skb_copy_datagram_iovec include/trace/events/skb.h:73 [inline] skb_copy_datagram_iter+0x29a/0x370 net/core/datagram.c:526 skb_copy_datagram_msg include/linux/skbuff.h:3933 [inline] __unix_dgram_recvmsg+0x403/0xb90 net/unix/af_unix.c:2485 unix_dgram_recvmsg+0xc4/0xf0 net/unix/af_unix.c:2543 sock_recvmsg_nosec net/socket.c:1015 [inline] ____sys_recvmsg+0x49c/0x5a0 net/socket.c:2721 ___sys_recvmsg+0xf2/0x180 net/socket.c:2765 do_recvmmsg+0x25e/0x6e0 net/socket.c:2859 __sys_recvmmsg net/socket.c:2938 [inline] __do_sys_recvmmsg net/socket.c:2961 [inline] __se_sys_recvmmsg net/socket.c:2954 [inline] __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2954 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 *** 2 locks held by syz-executor.1/11135: #0: ffff888043733d90 (&u->iolock){+.+.}-{3:3}, at: __unix_dgram_recvmsg+0x22a/0xb90 net/unix/af_unix.c:2443 #1: ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #1: ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #1: ffff88802efb9088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe4/0x4b0 net/can/j1939/transport.c:1244 stack backtrace: CPU: 1 PID: 11135 Comm: syz-executor.1 Not tainted 6.2.0-syzkaller-13467-g0988a0ea7919 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3098 [inline] check_prevs_add kernel/locking/lockdep.c:3217 [inline] validate_chain kernel/locking/lockdep.c:3832 [inline] __lock_acquire+0x2ec7/0x5d40 kernel/locking/lockdep.c:5056 lock_acquire kernel/locking/lockdep.c:5669 [inline] lock_acquire+0x1e3/0x670 kernel/locking/lockdep.c:5634 __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:1128 j1939_tp_rxtimer+0x3df/0x4b0 net/can/j1939/transport.c:1253 __run_hrtimer kernel/time/hrtimer.c:1685 [inline] __hrtimer_run_queues+0x690/0x1010 kernel/time/hrtimer.c:1749 hrtimer_run_softirq+0x17f/0x360 kernel/time/hrtimer.c:1766 __do_softirq+0x2e3/0xae3 kernel/softirq.c:571 invoke_softirq kernel/softirq.c:445 [inline] __irq_exit_rcu+0x114/0x190 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:645 RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:4038 [inline] RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:4048 [inline] RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:4082 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0xc9/0x140 kernel/rcu/tree.c:4066 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 c8 b7 95 RSP: 0018:ffffc90004a7f810 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffffffff8c7a0500 RCX: ffffc90006393000 RDX: 1ffffffff18f40ae RSI: 0000000000000002 RDI: ffffffff8c7a0570 RBP: 0000000000000002 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000000000 R15: ffffc90004a7fdc0 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_skb_copy_datagram_iovec include/trace/events/skb.h:73 [inline] skb_copy_datagram_iter+0x29a/0x370 net/core/datagram.c:526 skb_copy_datagram_msg include/linux/skbuff.h:3933 [inline] __unix_dgram_recvmsg+0x403/0xb90 net/unix/af_unix.c:2485 unix_dgram_recvmsg+0xc4/0xf0 net/unix/af_unix.c:2543 sock_recvmsg_nosec net/socket.c:1015 [inline] ____sys_recvmsg+0x49c/0x5a0 net/socket.c:2721 ___sys_recvmsg+0xf2/0x180 net/socket.c:2765 do_recvmmsg+0x25e/0x6e0 net/socket.c:2859 __sys_recvmmsg net/socket.c:2938 [inline] __do_sys_recvmmsg net/socket.c:2961 [inline] __se_sys_recvmmsg net/socket.c:2954 [inline] __x64_sys_recvmmsg+0x20f/0x260 net/socket.c:2954 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: 0033:0x7f987568c0f9 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:00007f987640d168 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007f98757ac050 RCX: 00007f987568c0f9 RDX: 0000000000010106 RSI: 00000000200000c0 RDI: 0000000000000004 RBP: 00007f98756e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f98758cfb1f R14: 00007f987640d300 R15: 0000000000022000 vxcan0: j1939_tp_rxtimer: 0xffff888027689800: 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: c8 .byte 0xc8 3e: b7 95 mov $0x95,%bh