====================================================== WARNING: possible circular locking dependency detected 6.6.0-rc6-syzkaller-00043-gdd72f9c7e512 #0 Not tainted ------------------------------------------------------ syz-executor744/5106 is trying to acquire lock: ffff888028eab5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888028eab5c8 (&jsk->sk_session_queue_lock){+.-.}-{2:2}, at: j1939_sk_queue_drop_all+0x3a/0x240 net/can/j1939/socket.c:139 but task is already holding lock: ffff888079f690d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] ffff888079f690d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x31/0x160 net/can/j1939/socket.c:1276 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+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 -> #1 (&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 invoke_softirq kernel/softirq.c:427 [inline] __irq_exit_rcu+0xf1/0x1b0 kernel/softirq.c:632 irq_exit_rcu+0x9/0x20 kernel/softirq.c:644 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:1042 [inline] debug_check_no_obj_freed+0x39e/0x420 lib/debugobjects.c:1063 free_pages_prepare mm/page_alloc.c:1142 [inline] free_unref_page_prepare+0x241/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 __slab_free+0x2f6/0x390 mm/slub.c:3715 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x14b/0x160 mm/kasan/quarantine.c:292 ____kasan_kmalloc mm/kasan/common.c:340 [inline] __kasan_kmalloc+0x23/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] syslog_print+0x121/0x9b0 kernel/printk/printk.c:1553 do_syslog+0x505/0x890 kernel/printk/printk.c:1732 __do_sys_syslog kernel/printk/printk.c:1824 [inline] __se_sys_syslog kernel/printk/printk.c:1822 [inline] __x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1822 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 (&jsk->sk_session_queue_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_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 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-executor744/5106: #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: ffff888079f690d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: spin_lock_bh include/linux/spinlock.h:356 [inline] #1: ffff888079f690d0 (&priv->j1939_socks_lock){+.-.}-{2:2}, at: j1939_sk_netdev_event_netdown+0x31/0x160 net/can/j1939/socket.c:1276 stack backtrace: CPU: 1 PID: 5106 Comm: syz-executor744 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_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 RIP: 0033:0x7fc42a6e92b9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 1a 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:00007fc42a683218 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc42a7791f8 RCX: 00007fc42a6e92b9 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 RBP: 00007fc42a7791f0 R08: 00007fc42a682fa4 R09: 0000000000000000 R10: 0000000000000014 R11: 0000000000000246 R12: 00007fc42a7791fc R13: 00007fc42a73f5dc R14: 6c756e2f7665642f R15: 00007fc42a73f01d