------------[ cut here ]------------
ida_free called for id=1536 which is not allocated.
WARNING: CPU: 0 PID: 7104 at lib/idr.c:592 ida_free+0x280/0x310
Modules linked in:
CPU: 0 UID: 0 PID: 7104 Comm: syz.0.490 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:ida_free+0x280/0x310
Code: 00 00 00 00 fc ff df 48 8b 5c 24 10 48 8b 7c 24 40 48 89 de e8 d1 8a 0c 00 90 48 c7 c7 80 ee ba 8c 44 89 fe e8 11 87 12 f6 90 <0f> 0b 90 90 eb 34 e8 95 02 4f f6 49 bd 00 00 00 00 00 fc ff df eb
RSP: 0018:ffffc90001d2f980 EFLAGS: 00010246
RAX: 876c797e99de3a00 RBX: 0000000000000a02 RCX: ffff88802349b980
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: ffffc90001d2fa70 R08: ffff88804b024293 R09: 1ffff11009604852
R10: dffffc0000000000 R11: ffffed1009604853 R12: 1ffff920003a5f34
R13: dffffc0000000000 R14: ffff88810e8f1200 R15: 0000000000000600
FS:  00007f8127ca86c0(0000) GS:ffff8880b8613000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2b266e CR3: 0000000028f48000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 free_uts_ns+0x101/0x160
 free_nsproxy+0x9b/0x350
 do_exit+0x6b0/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8126d8eba9
Code: Unable to access opcode bytes at 0x7f8126d8eb7f.
RSP: 002b:00007f8127ca80e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007f8126fd5fa8 RCX: 00007f8126d8eba9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f8126fd5fac
RBP: 00007f8126fd5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8126fd6038 R14: 00007ffecd5e6890 R15: 00007ffecd5e6978
 </TASK>
