Warning: Permanently added '10.128.0.168' (ECDSA) to the list of known hosts.
executing program
syzkaller login: [   74.881748][ T9804] IPVS: ftp: loaded support on port[0] = 21
[   74.915018][ T9804] netlink: 16 bytes leftover after parsing attributes in process `syz-executor738'.
[   74.966172][ T9804] ------------[ cut here ]------------
[   74.971710][ T9804] refcount_t: underflow; use-after-free.
[   74.977802][ T9804] WARNING: CPU: 1 PID: 9804 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0
[   74.987181][ T9804] Kernel panic - not syncing: panic_on_warn set ...
[   74.993768][ T9804] CPU: 1 PID: 9804 Comm: syz-executor738 Not tainted 5.6.0-rc6-syzkaller #0
[   75.002427][ T9804] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   75.012521][ T9804] Call Trace:
[   75.015806][ T9804]  dump_stack+0x188/0x20d
[   75.020143][ T9804]  ? refcount_warn_saturate+0x170/0x1e0
[   75.025684][ T9804]  panic+0x2e3/0x75c
[   75.029582][ T9804]  ? add_taint.cold+0x16/0x16
[   75.034284][ T9804]  ? __probe_kernel_read+0x188/0x1d0
[   75.039558][ T9804]  ? __warn.cold+0x14/0x35
[   75.043982][ T9804]  ? __warn+0xd5/0x1c8
[   75.048052][ T9804]  ? refcount_warn_saturate+0x1d1/0x1e0
[   75.053607][ T9804]  __warn.cold+0x2f/0x35
[   75.057868][ T9804]  ? refcount_warn_saturate+0x1d1/0x1e0
[   75.063403][ T9804]  report_bug+0x27b/0x2f0
[   75.067728][ T9804]  do_error_trap+0x12b/0x220
[   75.072310][ T9804]  ? refcount_warn_saturate+0x1d1/0x1e0
[   75.077853][ T9804]  do_invalid_op+0x32/0x40
[   75.082260][ T9804]  ? refcount_warn_saturate+0x1d1/0x1e0
[   75.087799][ T9804]  invalid_op+0x23/0x30
[   75.091946][ T9804] RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0
[   75.098111][ T9804] Code: e9 db fe ff ff 48 89 df e8 0c 06 20 fe e9 8a fe ff ff e8 d2 47 e3 fd 48 c7 c7 00 aa 51 88 c6 05 24 4e d2 06 01 e8 b7 58 b5 fd <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55
[   75.117705][ T9804] RSP: 0018:ffffc90002077d38 EFLAGS: 00010286
[   75.123762][ T9804] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   75.131723][ T9804] RDX: 0000000000000000 RSI: ffffffff815c06c1 RDI: fffff5200040ef99
[   75.139682][ T9804] RBP: 0000000000000003 R08: ffff88808ee0a400 R09: 0000000000000000
[   75.147644][ T9804] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809eba2040
[   75.155602][ T9804] R13: ffff88809eba2044 R14: 00000000000002ab R15: ffff8880a97340c0
[   75.163581][ T9804]  ? vprintk_func+0x81/0x17e
[   75.168171][ T9804]  ? refcount_warn_saturate+0x1d1/0x1e0
[   75.173709][ T9804]  free_nsproxy+0x445/0x4a0
[   75.178208][ T9804]  switch_task_namespaces+0xaa/0xc0
[   75.183412][ T9804]  do_exit+0xb2f/0x2dd0
[   75.187588][ T9804]  ? mm_update_next_owner+0x7a0/0x7a0
[   75.192955][ T9804]  ? up_read+0x1ab/0x750
[   75.197227][ T9804]  ? mark_held_locks+0x9f/0xe0
[   75.201986][ T9804]  ? down_read_non_owner+0x470/0x470
[   75.207265][ T9804]  ? handle_mm_fault+0x491/0xa10
[   75.212191][ T9804]  do_group_exit+0x125/0x340
[   75.216772][ T9804]  __x64_sys_exit_group+0x3a/0x50
[   75.221787][ T9804]  do_syscall_64+0xf6/0x7d0
[   75.226291][ T9804]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   75.232171][ T9804] RIP: 0033:0x43f998
[   75.236059][ T9804] Code: Bad RIP value.
[   75.240107][ T9804] RSP: 002b:00007ffc602c8c48 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[   75.248506][ T9804] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000043f998
[   75.256513][ T9804] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
[   75.264475][ T9804] RBP: 00000000004bfa10 R08: 00000000000000e7 R09: ffffffffffffffd0
[   75.272441][ T9804] R10: 0000000120080522 R11: 0000000000000246 R12: 0000000000000001
[   75.280424][ T9804] R13: 00000000006d11c0 R14: 0000000000000000 R15: 0000000000000000
[   75.290008][ T9804] Kernel Offset: disabled
[   75.294434][ T9804] Rebooting in 86400 seconds..