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kernel BUG at net/l2tp/l2tp_core.c:1572!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:l2tp_session_free net/l2tp/l2tp_core.c:1572 [inline]
RIP: 0010:l2tp_session_free+0x218/0x250 net/l2tp/l2tp_core.c:1565
Code: 89 ef e8 1b 04 5a fc e9 4b ff ff ff e8 51 94 33 fa 4c 89 e7 e8 b9 c8 e1 fe e9 39 ff ff ff e8 3f 94 33 fa 0f 0b e8 38 94 33 fa <0f> 0b 4c 89 e7 e8 7e a9 72 fa e9 48 fe ff ff 48 89 df e8 71 a9 72
RSP: 0018:ffffc90000007d28 EFLAGS: 00010246
RAX: ffffffff89886580 RBX: ffff8880a88d9800 RCX: ffffffff8740393d
RDX: 0000000000000000 RSI: ffffffff87403a88 RDI: 0000000000000005
RBP: ffff888092849800 R08: ffffffff89886580 R09: ffffed101250931a
R10: ffff8880928498cb R11: ffffed1012509319 R12: 0000000000000000
R13: ffff888097e084a8 R14: ffffc90000007e98 R15: ffffffff89886580
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000080e3dc8 CR3: 0000000009879000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 l2tp_session_dec_refcount net/l2tp/l2tp_core.h:257 [inline]
 pppol2tp_session_destruct+0x12e/0x180 net/l2tp/l2tp_ppp.c:424
 __sk_destruct+0x4b/0x7c0 net/core/sock.c:1785
 sk_destruct+0xc6/0x100 net/core/sock.c:1829
 __sk_free+0xef/0x3d0 net/core/sock.c:1840
 sk_free+0x78/0xa0 net/core/sock.c:1851
 sock_put include/net/sock.h:1780 [inline]
 pppol2tp_put_sk+0x9b/0xd0 net/l2tp/l2tp_ppp.c:408
 rcu_do_batch kernel/rcu/tree.c:2396 [inline]
 rcu_core+0x59f/0x1370 kernel/rcu/tree.c:2623
 __do_softirq+0x26c/0x9f7 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0x192/0x1d0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:546 [inline]
 smp_apic_timer_interrupt+0x19e/0x600 arch/x86/kernel/apic/apic.c:1107
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: cc cc cc cc cc cc cc cc cc cc cc cc e9 07 00 00 00 0f 00 2d 84 9c 4a 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 74 9c 4a 00 fb f4 <c3> cc 41 56 41 55 41 54 55 53 e8 33 9c 83 f9 e8 be c8 bf fb 0f 1f
RSP: 0018:ffffffff89807c50 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
RAX: ffffffff89886580 RBX: 0000000000000000 RCX: 1ffffffff15173ba
RDX: 0000000000000000 RSI: ffffffff87de1248 RDI: ffffffff89886e00
RBP: ffff88821a898064 R08: 0000000000000000 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88821a898064
R13: 1ffffffff1300f95 R14: ffff88821a898065 R15: 0000000000000001
 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:111 [inline]
 acpi_safe_halt+0x8d/0x110 drivers/acpi/processor_idle.c:108
 acpi_idle_do_entry+0xa9/0xe0 drivers/acpi/processor_idle.c:525
 acpi_idle_enter+0x437/0xb20 drivers/acpi/processor_idle.c:651
 cpuidle_enter_state+0xdd/0xd60 drivers/cpuidle/cpuidle.c:234
 cpuidle_enter+0x4a/0xa0 drivers/cpuidle/cpuidle.c:345
 call_cpuidle kernel/sched/idle.c:117 [inline]
 cpuidle_idle_call kernel/sched/idle.c:207 [inline]
 do_idle+0x42f/0x690 kernel/sched/idle.c:269
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:365
 start_kernel+0x9be/0x9fb init/main.c:1041
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242
Modules linked in:
---[ end trace 54b49e784da2e192 ]---
RIP: 0010:l2tp_session_free net/l2tp/l2tp_core.c:1572 [inline]
RIP: 0010:l2tp_session_free+0x218/0x250 net/l2tp/l2tp_core.c:1565
Code: 89 ef e8 1b 04 5a fc e9 4b ff ff ff e8 51 94 33 fa 4c 89 e7 e8 b9 c8 e1 fe e9 39 ff ff ff e8 3f 94 33 fa 0f 0b e8 38 94 33 fa <0f> 0b 4c 89 e7 e8 7e a9 72 fa e9 48 fe ff ff 48 89 df e8 71 a9 72
RSP: 0018:ffffc90000007d28 EFLAGS: 00010246
RAX: ffffffff89886580 RBX: ffff8880a88d9800 RCX: ffffffff8740393d
RDX: 0000000000000000 RSI: ffffffff87403a88 RDI: 0000000000000005
RBP: ffff888092849800 R08: ffffffff89886580 R09: ffffed101250931a
R10: ffff8880928498cb R11: ffffed1012509319 R12: 0000000000000000
R13: ffff888097e084a8 R14: ffffc90000007e98 R15: ffffffff89886580
FS:  0000000000000000(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000080e3dc8 CR3: 0000000009879000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400