IPVS: ftp: loaded support on port[0] = 21
netlink: 16 bytes leftover after parsing attributes in process `syz-executor632'.
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 7081 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 7081 Comm: syz-executor632 Not tainted 5.6.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x35 kernel/panic.c:582
 report_bug+0x27b/0x2f0 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:175 [inline]
 fixup_bug arch/x86/kernel/traps.c:170 [inline]
 do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0 lib/refcount.c:28
Code: e9 db fe ff ff 48 89 df e8 bc 14 1e fe e9 8a fe ff ff e8 62 8b e0 fd 48 c7 c7 c0 db 71 88 c6 05 45 5a f1 06 01 e8 87 03 b2 fd <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55
RSP: 0018:ffffc900018c7d38 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815ca081 RDI: fffff52000318f99
RBP: 0000000000000003 R08: ffff88809d6ca3c0 R09: ffffed1015ce66a1
R10: ffff8880ae733507 R11: ffffed1015ce66a0 R12: ffff88809d4da040
R13: ffff88809d4da044 R14: 00000000000002ab R15: ffff888092fda0c0
 refcount_sub_and_test include/linux/refcount.h:261 [inline]
 refcount_dec_and_test include/linux/refcount.h:281 [inline]
 put_net include/net/net_namespace.h:264 [inline]
 free_nsproxy+0x445/0x4a0 kernel/nsproxy.c:206
 switch_task_namespaces+0xaa/0xc0 kernel/nsproxy.c:252
 do_exit+0xb2f/0x2dd0 kernel/exit.c:794
 do_group_exit+0x125/0x340 kernel/exit.c:893
 __do_sys_exit_group kernel/exit.c:904 [inline]
 __se_sys_exit_group kernel/exit.c:902 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:902
 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x43f998
Code: Bad RIP value.
RSP: 002b:00007fff08450138 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000043f998
RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001
RBP: 00000000004bfa10 R08: 00000000000000e7 R09: ffffffffffffffd0
R10: 0000000120080522 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000006d11c0 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..