R13: 00007fbcb15e6038 R14: 00007fbcb15e5fa0 R15: 00007fbcb170fa28 ------------[ cut here ]------------ ida_free called for id=2187 which is not allocated. WARNING: CPU: 0 PID: 14576 at lib/idr.c:592 ida_free+0x280/0x310 lib/idr.c:592 Modules linked in: CPU: 0 UID: 0 PID: 14576 Comm: syz.8.2104 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:ida_free+0x280/0x310 lib/idr.c:592 Code: 00 00 00 00 fc ff df 48 8b 5c 24 10 48 8b 7c 24 40 48 89 de e8 71 2c 0c 00 90 48 c7 c7 a0 7b 76 8c 44 89 fe e8 41 11 54 f6 90 <0f> 0b 90 90 eb 34 e8 85 a2 90 f6 49 bd 00 00 00 00 00 fc ff df eb RSP: 0018:ffffc900175a7b60 EFLAGS: 00010246 RAX: 3aea96b38881d500 RBX: 0000000000000a02 RCX: ffff888025790000 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc900175a7c60 R08: ffff8880b8824293 R09: 1ffff11017104852 R10: dffffc0000000000 R11: ffffed1017104853 R12: 1ffff92002eb4f70 R13: dffffc0000000000 R14: ffff88804a1eef00 R15: 000000000000088b FS: 00007fbcb23046c0(0000) GS:ffff888126373000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b34163fff CR3: 0000000055c92000 CR4: 00000000003526f0 Call Trace: copy_mnt_ns+0x197/0x820 fs/namespace.c:4168 create_new_namespaces+0xd1/0x720 kernel/nsproxy.c:78 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:218 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3132 __do_sys_unshare kernel/fork.c:3203 [inline] __se_sys_unshare kernel/fork.c:3201 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fbcb138eec9 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:00007fbcb2304038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fbcb15e5fa0 RCX: 00007fbcb138eec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000002a020400 RBP: 00007fbcb2304090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007fbcb15e6038 R14: 00007fbcb15e5fa0 R15: 00007fbcb170fa28