------------[ cut here ]------------ kernel BUG at net/l2tp/l2tp_core.c:1572! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.8.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:l2tp_session_free+0x218/0x250 net/l2tp/l2tp_core.c:1572 Code: 89 ef e8 8b 4a 4d fc e9 4b ff ff ff e8 41 b2 29 fa 4c 89 e7 e8 49 f4 e1 fe e9 39 ff ff ff e8 2f b2 29 fa 0f 0b e8 28 b2 29 fa <0f> 0b 4c 89 e7 e8 1e 01 69 fa e9 48 fe ff ff 48 89 df e8 11 01 69 RSP: 0018:ffffc90000da8d60 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888095ffa400 RCX: ffffffff87499cfd RDX: ffff8880a9632340 RSI: ffffffff87499e48 RDI: 0000000000000005 RBP: ffff888097f97800 R08: 0000000000000000 R09: ffff888097f978cb R10: 0000000042114dda R11: 0000000000000000 R12: 0000000000000000 R13: ffff88809f435030 R14: 0000000000000000 R15: ffff8880a9632340 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1b5cb0ae78 CR3: 0000000009a79000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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/0x860 net/core/sock.c:1785 sk_destruct+0xbd/0xe0 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+0x5c7/0x1160 kernel/rcu/tree.c:2623 __do_softirq+0x34c/0xa60 kernel/softirq.c:292 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:711 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline] run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline] do_softirq_own_stack+0x111/0x170 arch/x86/kernel/irq_64.c:77 invoke_softirq kernel/softirq.c:387 [inline] __irq_exit_rcu kernel/softirq.c:417 [inline] irq_exit_rcu+0x229/0x270 kernel/softirq.c:429 sysvec_apic_timer_interrupt+0x12d/0x220 arch/x86/kernel/apic/apic.c:1091 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:596 RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61 Code: ff 4c 89 ef e8 83 9c cb f9 e9 8e fe ff ff 48 89 df e8 76 9c cb f9 eb 8a cc cc cc cc e9 07 00 00 00 0f 00 2d 24 a9 61 00 fb f4 90 e9 07 00 00 00 0f 00 2d 14 a9 61 00 f4 c3 cc cc 55 53 e8 c9 RSP: 0018:ffffc90000d3fc88 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff155cad2 RDX: ffff8880a9632340 RSI: ffffffff87e706f8 RDI: ffff8880a9632bc0 RBP: ffff8880a6655864 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880a6655864 R13: 1ffff920001a7f9b R14: ffff8880a6655865 R15: 0000000000000001 arch_safe_halt arch/x86/include/asm/paravirt.h:150 [inline] acpi_safe_halt+0x8d/0x110 drivers/acpi/processor_idle.c:111 acpi_idle_do_entry+0x15c/0x1b0 drivers/acpi/processor_idle.c:525 acpi_idle_enter+0x3f9/0xab0 drivers/acpi/processor_idle.c:651 cpuidle_enter_state+0xff/0x960 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+0x431/0x6a0 kernel/sched/idle.c:269 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:365 start_secondary+0x2b3/0x370 arch/x86/kernel/smpboot.c:268 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 Modules linked in: ---[ end trace 2ea598228637e285 ]--- RIP: 0010:l2tp_session_free+0x218/0x250 net/l2tp/l2tp_core.c:1572 Code: 89 ef e8 8b 4a 4d fc e9 4b ff ff ff e8 41 b2 29 fa 4c 89 e7 e8 49 f4 e1 fe e9 39 ff ff ff e8 2f b2 29 fa 0f 0b e8 28 b2 29 fa <0f> 0b 4c 89 e7 e8 1e 01 69 fa e9 48 fe ff ff 48 89 df e8 11 01 69 RSP: 0018:ffffc90000da8d60 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff888095ffa400 RCX: ffffffff87499cfd RDX: ffff8880a9632340 RSI: ffffffff87499e48 RDI: 0000000000000005 RBP: ffff888097f97800 R08: 0000000000000000 R09: ffff888097f978cb R10: 0000000042114dda R11: 0000000000000000 R12: 0000000000000000 R13: ffff88809f435030 R14: 0000000000000000 R15: ffff8880a9632340 FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1b5cb0ae78 CR3: 0000000009a79000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400