====================================================== WARNING: possible circular locking dependency detected 6.2.0-syzkaller-13467-g0988a0ea7919 #0 Not tainted ------------------------------------------------------ syz-executor.5/14734 is trying to acquire lock: ffff8880731035c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff8880731035c8 (&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: ffff88807da490d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] ffff88807da490d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2c/0x160 net/can/j1939/socket.c:1269 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: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_session_cancel+0x16a/0x250 net/can/j1939/transport.c:1139 j1939_tp_txtimer+0x1349/0x2be0 net/can/j1939/transport.c:1194 __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 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 (&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 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_call_function_single+0x97/0xc0 arch/x86/kernel/smp.c:243 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:653 lock_is_held_type+0x103/0x140 kernel/locking/lockdep.c:5717 xa_entry include/linux/xarray.h:1198 [inline] xas_next include/linux/xarray.h:1865 [inline] filemap_get_read_batch+0x693/0x910 mm/filemap.c:2378 filemap_get_pages+0x1b7/0x1620 mm/filemap.c:2594 filemap_read+0x35e/0xc70 mm/filemap.c:2693 generic_file_read_iter+0x3ad/0x5b0 mm/filemap.c:2840 ext4_file_read_iter+0x1d9/0x690 fs/ext4/file.c:147 call_read_iter include/linux/fs.h:1845 [inline] generic_file_splice_read+0x182/0x4b0 fs/splice.c:402 do_splice_to+0x1b9/0x240 fs/splice.c:885 splice_direct_to_actor+0x2ab/0x8a0 fs/splice.c:957 do_splice_direct+0x1ab/0x280 fs/splice.c:1066 do_sendfile+0xb19/0x12c0 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1323 [inline] __se_sys_sendfile64 fs/read_write.c:1309 [inline] __x64_sys_sendfile64+0x1d0/0x210 fs/read_write.c:1309 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 (&jsk->sk_session_queue_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_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_close_many+0x309/0x630 net/core/dev.c:1530 unregister_netdevice_many_notify+0x416/0x19f0 net/core/dev.c:10816 rtnl_delete_link net/core/rtnetlink.c:3191 [inline] rtnl_dellink+0x3a8/0xac0 net/core/rtnetlink.c:3243 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 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.5/14734: #0: ffffffff8e103108 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:75 [inline] #0: ffffffff8e103108 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x3e8/0xd50 net/core/rtnetlink.c:6171 #1: ffff88807da490d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:355 [inline] #1: ffff88807da490d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x2c/0x160 net/can/j1939/socket.c:1269 stack backtrace: CPU: 0 PID: 14734 Comm: syz-executor.5 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_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_close_many+0x309/0x630 net/core/dev.c:1530 unregister_netdevice_many_notify+0x416/0x19f0 net/core/dev.c:10816 rtnl_delete_link net/core/rtnetlink.c:3191 [inline] rtnl_dellink+0x3a8/0xac0 net/core/rtnetlink.c:3243 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 RIP: 0033:0x7fb7f4e8c0f9 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:00007fb7f5b4b168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fb7f4fabf80 RCX: 00007fb7f4e8c0f9 RDX: 0000000000000000 RSI: 00000000200002c0 RDI: 000000000000000d RBP: 00007fb7f4ee7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd156cd36f R14: 00007fb7f5b4b300 R15: 0000000000022000