syzbot

------------[ cut here ]------------
ida_free called for id=1969 which is not allocated.
WARNING: CPU: 0 PID: 14212 at lib/idr.c:592 ida_free+0x1f9/0x2e0 lib/idr.c:592
Modules linked in:
CPU: 0 UID: 0 PID: 14212 Comm: syz-executor Tainted: G     U              syzkaller #0 PREEMPT(full) 
Tainted: [U]=USER
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:ida_free+0x1f9/0x2e0 lib/idr.c:592
Code: 7c f6 41 83 fe 3e 76 72 e8 d4 44 7c f6 48 8b 7c 24 28 4c 89 ee e8 77 01 0d 00 90 48 c7 c7 c0 73 cf 8c 89 ee e8 a8 1a 3b f6 90 <0f> 0b 90 90 e8 ae 44 7c f6 48 b8 00 00 00 00 00 fc ff df 48 01 c3
RSP: 0000:ffffc900033bf980 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 1ffff92000677f31 RCX: ffffffff81797ce8
RDX: ffff8880789bdac0 RSI: ffffffff81797cf5 RDI: 0000000000000001
RBP: 00000000000007b1 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: fffffffffffd36a0 R12: ffff888032ec1600
R13: 0000000000000293 R14: 00000000000003b1 R15: ffff888032ec1670
FS:  0000000000000000(0000) GS:ffff888124e8c000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b32d01ff8 CR3: 000000006a4c2000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 free_mnt_ns+0xe0/0x110 fs/namespace.c:4096
 namespace_unlock+0x542/0x920 fs/namespace.c:1701
 put_mnt_ns fs/namespace.c:6135 [inline]
 put_mnt_ns+0xf5/0x120 fs/namespace.c:6126
 free_nsproxy+0x3a/0x400 kernel/nsproxy.c:188
 put_nsproxy include/linux/nsproxy.h:107 [inline]
 switch_task_namespaces+0xeb/0x100 kernel/nsproxy.c:241
 do_exit+0x86a/0x2bf0 kernel/exit.c:965
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1107
 get_signal+0x2671/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x790 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x85/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x419/0x4b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f917c78d8dc
Code: Unable to access opcode bytes at 0x7f917c78d8b2.
RSP: 002b:00007ffd3ae93c80 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: fffffffffffffe00 RBX: 0000000000000003 RCX: 00007f917c78d8dc
RDX: 0000000000000030 RSI: 00007ffd3ae93d40 RDI: 00000000000000f9
RBP: 00007ffd3ae93cec R08: 0000000000000000 R09: 00007ffd3ae939f7
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000263
R13: 00000000000927c0 R14: 000000000011e23a R15: 00007ffd3ae93d40
 </TASK>