------------[ cut here ]------------ ida_free called for id=2050 which is not allocated. WARNING: CPU: 0 PID: 6354 at lib/idr.c:592 ida_free+0x280/0x310 lib/idr.c:592 Modules linked in: CPU: 0 UID: 0 PID: 6354 Comm: syz.4.113 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 81 2c 0c 00 90 48 c7 c7 20 27 74 8c 44 89 fe e8 91 1c 59 f6 90 <0f> 0b 90 90 eb 34 e8 75 ae 95 f6 49 bd 00 00 00 00 00 fc ff df eb RSP: 0018:ffffc9000b177880 EFLAGS: 00010246 RAX: 5895f9b26f6df800 RBX: 0000000000000a06 RCX: ffff888028fb9e40 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000002 RBP: ffffc9000b177968 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1b7a118 R12: 1ffff9200162ef14 R13: dffffc0000000000 R14: 000000000000003b R15: 0000000000000802 FS: 0000000000000000(0000) GS:ffff88812639b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fda6c3156c0 CR3: 0000000072fb0000 CR4: 00000000003526f0 Call Trace: free_mnt_ns+0x52/0xe0 fs/namespace.c:4096 namespace_unlock+0x529/0x760 fs/namespace.c:1701 free_nsproxy+0x3e/0x350 kernel/nsproxy.c:188 do_exit+0x6b0/0x2300 kernel/exit.c:960 do_group_exit+0x21c/0x2d0 kernel/exit.c:1102 get_signal+0x1285/0x1340 kernel/signal.c:3034 arch_do_signal_or_restart+0xa0/0x790 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop+0x72/0x110 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+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fea1078eec9 Code: Unable to access opcode bytes at 0x7fea1078ee9f. RSP: 002b:00007fea1161d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: fffffffffffffff4 RBX: 00007fea109e6180 RCX: 00007fea1078eec9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000022020400 RBP: 00007fea10811f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fea109e6218 R14: 00007fea109e6180 R15: 00007ffcc5929868