[[0;32m OK [0m] Started Getty on tty2.
[[0;32m OK [0m] Started Getty on tty1.
[[0;32m OK [0m] Started Serial Getty on ttyS0.
[[0;32m OK [0m] Reached target Login Prompts.
[[0;32m OK [0m] Reached target Multi-User System.
[[0;32m OK [0m] Reached target Graphical Interface.
Starting Update UTMP about System Runlevel Changes...
[[0;32m OK [0m] Started Update UTMP about System Runlevel Changes.
Starting Load/Save RF Kill Switch Status...
[[0;32m OK [0m] Started Load/Save RF Kill Switch Status.
Debian GNU/Linux 9 syzkaller ttyS0
Warning: Permanently added '10.128.10.12' (ECDSA) to the list of known hosts.
executing program
syzkaller login: [ 56.111824][ T6804] IPVS: ftp: loaded support on port[0] = 21
[ 56.233176][ C1] ------------[ cut here ]------------
[ 56.238708][ C1] kernel BUG at net/l2tp/l2tp_core.c:1572!
[ 56.244874][ C1] invalid opcode: 0000 [#1] PREEMPT SMP KASAN
[ 56.250939][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.7.0-syzkaller #0
[ 56.258467][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 56.268602][ C1] RIP: 0010:l2tp_session_free+0x218/0x250
[ 56.274537][ C1] 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
[ 56.294206][ C1] RSP: 0018:ffffc90000da8d28 EFLAGS: 00010246
[ 56.300244][ C1] RAX: ffff8880a9632340 RBX: ffff88809e1e1800 RCX: ffffffff8740393d
[ 56.308282][ C1] RDX: 0000000000000000 RSI: ffffffff87403a88 RDI: 0000000000000005
[ 56.316234][ C1] RBP: ffff88809f5f1000 R08: ffff8880a9632340 R09: ffffed1013ebe21a
[ 56.324198][ C1] R10: ffff88809f5f10cb R11: ffffed1013ebe219 R12: 0000000000000000
[ 56.332151][ C1] R13: ffff88809f53b4a8 R14: ffffc90000da8e98 R15: ffff8880a9632340
[ 56.340444][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
[ 56.349343][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 56.355912][ C1] CR2: 000000000049f410 CR3: 0000000009879000 CR4: 00000000001406e0
[ 56.363857][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 56.371801][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 56.380015][ C1] Call Trace:
[ 56.383270][ C1]
[ 56.386103][ C1] pppol2tp_session_destruct+0x12e/0x180
[ 56.391721][ C1] ? pppol2tp_recvmsg+0x270/0x270
[ 56.396717][ C1] __sk_destruct+0x4b/0x7c0
[ 56.401291][ C1] sk_destruct+0xc6/0x100
[ 56.405688][ C1] __sk_free+0xef/0x3d0
[ 56.409824][ C1] sk_free+0x78/0xa0
[ 56.413690][ C1] pppol2tp_put_sk+0x9b/0xd0
[ 56.418975][ C1] rcu_core+0x59f/0x1370
[ 56.423202][ C1] ? __rcu_read_unlock+0x560/0x560
[ 56.428294][ C1] ? rcu_read_lock_sched_held+0x9c/0xd0
[ 56.433809][ C1] ? rcu_read_lock_any_held.part.0+0x50/0x50
[ 56.439761][ C1] __do_softirq+0x26c/0x9f7
[ 56.444261][ C1] irq_exit+0x192/0x1d0
[ 56.448388][ C1] smp_apic_timer_interrupt+0x19e/0x600
[ 56.453974][ C1] apic_timer_interrupt+0xf/0x20
[ 56.459190][ C1]
[ 56.462186][ C1] RIP: 0010:native_safe_halt+0xe/0x10
[ 56.467672][ C1] 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 cc 41 56 41 55 41 54 55 53 e8 33 9c 83 f9 e8 be c8 bf fb 0f 1f
[ 56.487272][ C1] RSP: 0018:ffffc90000d3fc70 EFLAGS: 00000293 ORIG_RAX: ffffffffffffff13
[ 56.496023][ C1] RAX: ffff8880a9632340 RBX: 0000000000000000 RCX: 1ffffffff15173ba
[ 56.504951][ C1] RDX: 0000000000000000 RSI: ffffffff87de1248 RDI: ffff8880a9632bc0
[ 56.513272][ C1] RBP: ffff88821af0a864 R08: 0000000000000000 R09: 0000000000000001
[ 56.521244][ C1] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88821af0a864
[ 56.529209][ C1] R13: 1ffff920001a7f99 R14: ffff88821af0a865 R15: 0000000000000001
[ 56.537183][ C1] ? acpi_safe_halt+0x88/0x110
[ 56.541922][ C1] acpi_safe_halt+0x8d/0x110
[ 56.546584][ C1] acpi_idle_do_entry+0xa9/0xe0
[ 56.551411][ C1] acpi_idle_enter+0x437/0xb20
[ 56.556147][ C1] ? acpi_idle_enter_bm+0x2d0/0x2d0
[ 56.561328][ C1] ? kvm_clock_read+0x14/0x30
[ 56.565981][ C1] ? kvm_sched_clock_read+0x5/0x10
[ 56.571062][ C1] ? sched_clock+0x2a/0x40
[ 56.575449][ C1] ? sched_clock_cpu+0x18/0x1b0
[ 56.580369][ C1] cpuidle_enter_state+0xdd/0xd60
[ 56.585365][ C1] ? assoc_array_gc+0x1200/0x1250
[ 56.590378][ C1] cpuidle_enter+0x4a/0xa0
[ 56.594791][ C1] do_idle+0x42f/0x690
[ 56.598843][ C1] ? arch_cpu_idle_exit+0x70/0x70
[ 56.603848][ C1] cpu_startup_entry+0x14/0x20
[ 56.608581][ C1] start_secondary+0x2f8/0x410
[ 56.613328][ C1] ? set_cpu_sibling_map+0x1ed0/0x1ed0
[ 56.618786][ C1] secondary_startup_64+0xa4/0xb0
[ 56.623799][ C1] Modules linked in:
[ 56.627758][ C1] ---[ end trace 47d528f33fca2214 ]---
[ 56.633256][ C1] RIP: 0010:l2tp_session_free+0x218/0x250
[ 56.638971][ C1] 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
[ 56.658624][ C1] RSP: 0018:ffffc90000da8d28 EFLAGS: 00010246
[ 56.665004][ C1] RAX: ffff8880a9632340 RBX: ffff88809e1e1800 RCX: ffffffff8740393d
[ 56.673059][ C1] RDX: 0000000000000000 RSI: ffffffff87403a88 RDI: 0000000000000005
[ 56.681024][ C1] RBP: ffff88809f5f1000 R08: ffff8880a9632340 R09: ffffed1013ebe21a
[ 56.689024][ C1] R10: ffff88809f5f10cb R11: ffffed1013ebe219 R12: 0000000000000000
[ 56.697219][ C1] R13: ffff88809f53b4a8 R14: ffffc90000da8e98 R15: ffff8880a9632340
[ 56.705262][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
[ 56.714394][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 56.721112][ C1] CR2: 000000000049f410 CR3: 0000000009879000 CR4: 00000000001406e0
[ 56.729168][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 56.737277][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 56.745742][ C1] Kernel panic - not syncing: Fatal exception in interrupt
[ 56.754245][ C1] Kernel Offset: disabled
[ 56.758671][ C1] Rebooting in 86400 seconds..