================================ WARNING: inconsistent lock state 6.1.0-rc5-syzkaller-01477-g7a168f560e3c #0 Not tainted -------------------------------- inconsistent {IN-SOFTIRQ-R} -> {SOFTIRQ-ON-W} usage. syz-executor.4/5249 [HC0[0]:SC0[0]:HE1:SE1] takes: ffff88807319b3b8 (clock-AF_INET6){+++-}-{2:2}, at: l2tp_tunnel_register+0x126/0x1210 net/l2tp/l2tp_core.c:1477 {IN-SOFTIRQ-R} state was registered at: lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_read_lock_bh include/linux/rwlock_api_smp.h:176 [inline] _raw_read_lock_bh+0x3f/0x70 kernel/locking/spinlock.c:252 rds_tcp_write_space+0x29/0x690 net/rds/tcp_send.c:184 tcp_new_space net/ipv4/tcp_input.c:5482 [inline] tcp_check_space+0x11b/0x810 net/ipv4/tcp_input.c:5501 tcp_write_xmit+0x1048/0x6140 net/ipv4/tcp_output.c:2700 tcp_tsq_write net/ipv4/tcp_output.c:1021 [inline] tcp_tsq_write+0x20c/0x360 net/ipv4/tcp_output.c:1008 tcp_tsq_handler+0x8e/0x200 net/ipv4/tcp_output.c:1030 tcp_tasklet_func+0x2d0/0x560 net/ipv4/tcp_output.c:1062 tasklet_action_common.constprop.0+0x201/0x2e0 kernel/softirq.c:797 __do_softirq+0x1fb/0xadc 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:306 irq event stamp: 175 hardirqs last enabled at (175): [] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline] hardirqs last enabled at (175): [] _raw_spin_unlock_irqrestore+0x54/0x70 kernel/locking/spinlock.c:194 hardirqs last disabled at (174): [] __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline] hardirqs last disabled at (174): [] _raw_spin_lock_irqsave+0x52/0x60 kernel/locking/spinlock.c:162 softirqs last enabled at (164): [] rcu_read_unlock_bh include/linux/rcupdate.h:816 [inline] softirqs last enabled at (164): [] l2tp_tunnel_get+0x3fb/0x750 net/l2tp/l2tp_core.c:219 softirqs last disabled at (162): [] rcu_read_unlock include/linux/rcupdate.h:779 [inline] softirqs last disabled at (162): [] net_generic include/net/netns/generic.h:48 [inline] softirqs last disabled at (162): [] l2tp_pernet net/l2tp/l2tp_core.c:125 [inline] softirqs last disabled at (162): [] l2tp_tunnel_get+0x14d/0x750 net/l2tp/l2tp_core.c:207 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(clock-AF_INET6); lock(clock-AF_INET6); *** DEADLOCK *** 1 lock held by syz-executor.4/5249: #0: ffff88804cb2f130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1721 [inline] #0: ffff88804cb2f130 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0xadc/0x1a10 net/l2tp/l2tp_ppp.c:675 stack backtrace: CPU: 1 PID: 5249 Comm: syz-executor.4 Not tainted 6.1.0-rc5-syzkaller-01477-g7a168f560e3c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 print_usage_bug kernel/locking/lockdep.c:222 [inline] valid_state kernel/locking/lockdep.c:3975 [inline] mark_lock_irq kernel/locking/lockdep.c:4184 [inline] mark_lock.part.0.cold+0x3a/0xd8 kernel/locking/lockdep.c:4634 mark_lock kernel/locking/lockdep.c:4598 [inline] mark_usage kernel/locking/lockdep.c:4547 [inline] __lock_acquire+0x893/0x56d0 kernel/locking/lockdep.c:5009 lock_acquire kernel/locking/lockdep.c:5668 [inline] lock_acquire+0x1e3/0x630 kernel/locking/lockdep.c:5633 __raw_write_lock include/linux/rwlock_api_smp.h:209 [inline] _raw_write_lock+0x2e/0x40 kernel/locking/spinlock.c:300 l2tp_tunnel_register+0x126/0x1210 net/l2tp/l2tp_core.c:1477 pppol2tp_connect+0xcdc/0x1a10 net/l2tp/l2tp_ppp.c:723 __sys_connect_file+0x153/0x1a0 net/socket.c:1976 __sys_connect+0x165/0x1a0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:2000 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: 0033:0x7f534b08c0d9 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:00007f534bd26168 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f534b1ac120 RCX: 00007f534b08c0d9 RDX: 000000000000002e RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00007f534b0e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd02504c8f R14: 00007f534bd26300 R15: 0000000000022000 BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 5249, name: syz-executor.4 preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 INFO: lockdep is turned off. Preemption disabled at: [<0000000000000000>] 0x0 CPU: 1 PID: 5249 Comm: syz-executor.4 Not tainted 6.1.0-rc5-syzkaller-01477-g7a168f560e3c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 __might_resched.cold+0x222/0x26b kernel/sched/core.c:9890 percpu_down_read include/linux/percpu-rwsem.h:49 [inline] cpus_read_lock+0x1b/0x140 kernel/cpu.c:310 static_key_slow_inc+0x12/0x20 kernel/jump_label.c:158 udp_tunnel_encap_enable include/net/udp_tunnel.h:187 [inline] setup_udp_tunnel_sock+0x43d/0x550 net/ipv4/udp_tunnel_core.c:81 l2tp_tunnel_register+0xc51/0x1210 net/l2tp/l2tp_core.c:1509 pppol2tp_connect+0xcdc/0x1a10 net/l2tp/l2tp_ppp.c:723 __sys_connect_file+0x153/0x1a0 net/socket.c:1976 __sys_connect+0x165/0x1a0 net/socket.c:1993 __do_sys_connect net/socket.c:2003 [inline] __se_sys_connect net/socket.c:2000 [inline] __x64_sys_connect+0x73/0xb0 net/socket.c:2000 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: 0033:0x7f534b08c0d9 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:00007f534bd26168 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f534b1ac120 RCX: 00007f534b08c0d9 RDX: 000000000000002e RSI: 0000000020000040 RDI: 0000000000000003 RBP: 00007f534b0e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffd02504c8f R14: 00007f534bd26300 R15: 0000000000022000