====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #0 Not tainted ------------------------------------------------------ syz-executor.1/7903 is trying to acquire lock: ffff88808597d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88808597d0d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_errqueue+0x96/0x150 net/can/j1939/socket.c:1083 but task is already holding lock: ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x47/0x480 net/can/j1939/transport.c:2183 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+0x35/0x50 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+0x51/0x3e0 net/can/j1939/transport.c:1564 j1939_sk_queue_activate_next_locked net/can/j1939/socket.c:181 [inline] j1939_sk_queue_activate_next+0x26c/0x3f0 net/can/j1939/socket.c:208 j1939_session_deactivate_activate_next net/can/j1939/transport.c:1108 [inline] j1939_session_completed net/can/j1939/transport.c:1222 [inline] j1939_xtp_rx_eoma_one net/can/j1939/transport.c:1395 [inline] j1939_xtp_rx_eoma+0x323/0x530 net/can/j1939/transport.c:1410 j1939_tp_cmd_recv net/can/j1939/transport.c:2099 [inline] j1939_tp_recv+0x88e/0x1050 net/can/j1939/transport.c:2144 j1939_can_recv+0x732/0xb20 net/can/j1939/main.c:112 deliver net/can/af_can.c:572 [inline] can_rcv_filter+0x349/0x7c0 net/can/af_can.c:606 can_receive+0x319/0x470 net/can/af_can.c:663 can_rcv+0x144/0x260 net/can/af_can.c:687 __netif_receive_skb_one_core net/core/dev.c:5527 [inline] __netif_receive_skb+0x1ca/0x530 net/core/dev.c:5641 process_backlog+0x385/0x760 net/core/dev.c:5969 __napi_poll+0xc7/0x470 net/core/dev.c:6531 napi_poll net/core/dev.c:6598 [inline] net_rx_action+0x78b/0x1010 net/core/dev.c:6731 __do_softirq+0x2ab/0x908 kernel/softirq.c:553 do_softirq+0x11b/0x1e0 kernel/softirq.c:454 __local_bh_enable_ip+0x1b5/0x1f0 kernel/softirq.c:381 ieee80211_rx_bss_info net/mac80211/ibss.c:1196 [inline] ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1613 [inline] ieee80211_ibss_rx_queued_mgmt+0x1aeb/0x2ce0 net/mac80211/ibss.c:1642 ieee80211_iface_process_skb net/mac80211/iface.c:1604 [inline] ieee80211_iface_work+0x7bd/0xcf0 net/mac80211/iface.c:1658 cfg80211_wiphy_work+0x21e/0x250 net/wireless/core.c:435 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x90f/0x1400 kernel/workqueue.c:2703 worker_thread+0xa5f/0xff0 kernel/workqueue.c:2784 kthread+0x2d3/0x370 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 -> #1 (&jsk->sk_session_queue_lock){+.-.}-{2:2}: __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_queue_drop_all+0x3a/0x240 net/can/j1939/socket.c:139 j1939_sk_netdev_event_netdown+0xed/0x160 net/can/j1939/socket.c:1282 j1939_netdev_notify+0x20d/0x2e0 net/can/j1939/main.c:381 notifier_call_chain+0x18c/0x3a0 kernel/notifier.c:93 __dev_notify_flags+0x359/0x650 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8678 do_setlink+0xfb2/0x4340 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3671 [inline] rtnl_newlink+0x17f6/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x87e/0x1030 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2558 ___sys_sendmsg net/socket.c:2612 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2641 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 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:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x39ff/0x7f70 kernel/locking/lockdep.c:5136 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_errqueue+0x96/0x150 net/can/j1939/socket.c:1083 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0xff/0x460 net/can/j1939/transport.c:299 j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_cancel_active_session+0x354/0x480 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x205/0x2e0 net/can/j1939/main.c:380 notifier_call_chain+0x18c/0x3a0 kernel/notifier.c:93 __dev_notify_flags+0x359/0x650 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8678 do_setlink+0xfb2/0x4340 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3671 [inline] rtnl_newlink+0x17f6/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x87e/0x1030 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2558 ___sys_sendmsg net/socket.c:2612 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2641 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 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.1/7903: #0: ffffffff8e4d2948 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:78 [inline] #0: ffffffff8e4d2948 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x828/0x1030 net/core/rtnetlink.c:6441 #1: ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_session_list_lock net/can/j1939/transport.c:238 [inline] #1: ffff88808597d088 (&priv->active_session_list_lock){+.-.}-{2:2}, at: j1939_cancel_active_session+0x47/0x480 net/can/j1939/transport.c:2183 stack backtrace: CPU: 0 PID: 7903 Comm: syz-executor.1 Not tainted 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #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+0x1e7/0x2d0 lib/dump_stack.c:106 check_noncircular+0x375/0x4a0 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+0x39ff/0x7f70 kernel/locking/lockdep.c:5136 lock_acquire+0x1e3/0x520 kernel/locking/lockdep.c:5753 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x35/0x50 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] j1939_sk_errqueue+0x96/0x150 net/can/j1939/socket.c:1083 __j1939_session_release net/can/j1939/transport.c:294 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0xff/0x460 net/can/j1939/transport.c:299 j1939_session_deactivate_locked net/can/j1939/transport.c:1086 [inline] j1939_cancel_active_session+0x354/0x480 net/can/j1939/transport.c:2194 j1939_netdev_notify+0x205/0x2e0 net/can/j1939/main.c:380 notifier_call_chain+0x18c/0x3a0 kernel/notifier.c:93 __dev_notify_flags+0x359/0x650 dev_change_flags+0xf0/0x1a0 net/core/dev.c:8678 do_setlink+0xfb2/0x4340 net/core/rtnetlink.c:2880 __rtnl_newlink net/core/rtnetlink.c:3671 [inline] rtnl_newlink+0x17f6/0x2070 net/core/rtnetlink.c:3718 rtnetlink_rcv_msg+0x87e/0x1030 net/core/rtnetlink.c:6444 netlink_rcv_skb+0x1df/0x430 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline] netlink_unicast+0x7dc/0x970 net/netlink/af_netlink.c:1368 netlink_sendmsg+0xa37/0xd70 net/netlink/af_netlink.c:1910 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2558 ___sys_sendmsg net/socket.c:2612 [inline] __sys_sendmsg+0x2b0/0x3a0 net/socket.c:2641 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f673647cae9 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:00007f6734dcc0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f673659c120 RCX: 00007f673647cae9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000006 RBP: 00007f67364c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f673659c120 R15: 00007ffd845d1838