R13: 00007fe09cfe6038 R14: 00007fe09cfe5fa0 R15: 00007fff55d7e6a8
 </TASK>
------------[ cut here ]------------
ida_free called for id=1418 which is not allocated.
WARNING: CPU: 3 PID: 10290 at lib/idr.c:592 ida_free+0x1f9/0x2e0 lib/idr.c:592
Modules linked in:
CPU: 3 UID: 0 PID: 10290 Comm: syz.2.1382 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:ida_free+0x1f9/0x2e0 lib/idr.c:592
Code: 75 f6 41 83 fe 3e 76 72 e8 34 3b 75 f6 48 8b 7c 24 28 4c 89 ee e8 47 39 0d 00 90 48 c7 c7 00 be cf 8c 89 ee e8 38 c6 33 f6 90 <0f> 0b 90 90 e8 0e 3b 75 f6 48 b8 00 00 00 00 00 fc ff df 48 01 c3
RSP: 0018:ffffc90004ca7940 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 1ffff92000994f29 RCX: ffffffff8179a5b8
RDX: ffff888022c02480 RSI: ffffffff8179a5c5 RDI: 0000000000000001
RBP: 000000000000058a R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888030b98f00
R13: 0000000000000293 R14: 000000000000018a R15: ffff888030b98f30
FS:  00007fe09db4d6c0(0000) GS:ffff8880d7171000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe09aff5f98 CR3: 0000000047af5000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 copy_mnt_ns+0x886/0xa90 fs/namespace.c:4168
 create_new_namespaces+0xd3/0xa90 kernel/nsproxy.c:78
 copy_namespaces+0x468/0x560 kernel/nsproxy.c:175
 copy_process+0x2820/0x76a0 kernel/fork.c:2183
 kernel_clone+0xfc/0x930 kernel/fork.c:2610
 __do_sys_clone+0xce/0x120 kernel/fork.c:2753
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4e0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe09cd8eec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe09db4cfe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007fe09cfe5fa0 RCX: 00007fe09cd8eec9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000a0400
RBP: 00007fe09db4d090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000002
R13: 00007fe09cfe6038 R14: 00007fe09cfe5fa0 R15: 00007fff55d7e6a8
 </TASK>