vxcan0: j1939_tp_rxtimer: 0xffff88806ef99c00: rx timeout, send abort vxcan0: j1939_tp_rxtimer: 0xffff88806ef9b400: rx timeout, send abort ====================================================== WARNING: possible circular locking dependency detected 6.2.0-syzkaller-10217-ga93e884edf61 #0 Not tainted ------------------------------------------------------ kworker/1:5/5171 is trying to acquire lock: ffff88804d6250d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88804d6250d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0xa3/0x1a0 net/can/j1939/socket.c:1081 but task is already holding lock: ffff88804d625088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88804d625088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88804d625088 (&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:5477 __netif_receive_skb+0x1f/0x1c0 net/core/dev.c:5591 process_backlog+0x279/0x850 net/core/dev.c:5919 __napi_poll+0xb8/0x870 net/core/dev.c:6480 napi_poll net/core/dev.c:6547 [inline] net_rx_action+0x9fd/0xdc0 net/core/dev.c:6657 __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:8566 dev_change_flags+0x11b/0x170 net/core/dev.c:8602 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:649 find_next_bit include/linux/find.h:65 [inline] srcu_readers_unlock_idx kernel/rcu/srcutree.c:435 [inline] srcu_readers_active_idx_check kernel/rcu/srcutree.c:455 [inline] try_check_zero+0x171/0x430 kernel/rcu/srcutree.c:1072 srcu_advance_state kernel/rcu/srcutree.c:1629 [inline] process_srcu+0x38b/0x1210 kernel/rcu/srcutree.c:1730 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 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 *** 4 locks held by kworker/1:5/5171: #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:639 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:666 [inline] #0: ffff888012472538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x86d/0x1820 kernel/workqueue.c:2361 #1: ffffc9000494fda8 ((work_completion)(&(&ssp->work)->work)){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1820 kernel/workqueue.c:2365 #2: ffffffff91e1cf78 (&ssp->srcu_gp_mutex){+.+.}-{3:3}, at: srcu_advance_state kernel/rcu/srcutree.c:1578 [inline] #2: ffffffff91e1cf78 (&ssp->srcu_gp_mutex){+.+.}-{3:3}, at: process_srcu+0x30/0x1210 kernel/rcu/srcutree.c:1730 #3: ffff88804d625088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #3: ffff88804d625088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #3: ffff88804d625088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_tp_rxtimer+0xe4/0x4b0 net/can/j1939/transport.c:1244 stack backtrace: CPU: 1 PID: 5171 Comm: kworker/1:5 Not tainted 6.2.0-syzkaller-10217-ga93e884edf61 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 Workqueue: rcu_gp process_srcu 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:649 RIP: 0010:find_next_bit include/linux/find.h:65 [inline] RIP: 0010:srcu_readers_unlock_idx kernel/rcu/srcutree.c:435 [inline] RIP: 0010:srcu_readers_active_idx_check kernel/rcu/srcutree.c:455 [inline] RIP: 0010:try_check_zero+0x171/0x430 kernel/rcu/srcutree.c:1072 Code: 44 24 20 41 0f b6 04 24 48 63 d2 40 38 c5 7c 08 84 c0 0f 85 ed 01 00 00 8b 35 8b 83 0a 0d 48 c7 c7 58 d9 77 8e e8 6f b3 ae 02 <49> 89 c5 41 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 b5 01 00 00 44 RSP: 0018:ffffc9000494fbc8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: ffff888020b78000 RSI: ffffffff841c0c4b RDI: 0000000000000007 RBP: 0000000000000003 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000000 R12: fffffbfff1cefb68 R13: ffffffff91e1d100 R14: ffff88801d420000 R15: ffffffff91e1ce20 srcu_advance_state kernel/rcu/srcutree.c:1629 [inline] process_srcu+0x38b/0x1210 kernel/rcu/srcutree.c:1730 process_one_work+0x9bf/0x1820 kernel/workqueue.c:2390 worker_thread+0x669/0x1090 kernel/workqueue.c:2537 kthread+0x2e8/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 vxcan0: j1939_xtp_rx_abort_one: 0xffff88806ef99c00: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. vxcan0: j1939_xtp_rx_abort_one: 0xffff88806ef9b400: 0x00000: (3) A timeout occurred and this is the connection abort to close the session. ---------------- Code disassembly (best guess): 0: 44 24 20 rex.R and $0x20,%al 3: 41 0f b6 04 24 movzbl (%r12),%eax 8: 48 63 d2 movslq %edx,%rdx b: 40 38 c5 cmp %al,%bpl e: 7c 08 jl 0x18 10: 84 c0 test %al,%al 12: 0f 85 ed 01 00 00 jne 0x205 18: 8b 35 8b 83 0a 0d mov 0xd0a838b(%rip),%esi # 0xd0a83a9 1e: 48 c7 c7 58 d9 77 8e mov $0xffffffff8e77d958,%rdi 25: e8 6f b3 ae 02 callq 0x2aeb399 * 2a: 49 89 c5 mov %rax,%r13 <-- trapping instruction 2d: 41 0f b6 04 24 movzbl (%r12),%eax 32: 40 38 c5 cmp %al,%bpl 35: 7c 08 jl 0x3f 37: 84 c0 test %al,%al 39: 0f 85 b5 01 00 00 jne 0x1f4 3f: 44 rex.R