Extracting prog: 1m18.24721766s Minimizing prog: 1m11.039402277s Simplifying prog options: 3m23.210542848s Extracting C: 1m41.107326472s Simplifying C: 8m15.500462783s extracting reproducer from 24 programs first checking the prog from the crash report single: executing 1 programs separately with timeout 30s testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) (fail_nth: 2) program crashed: general protection fault in put_ipc_ns single: successfully extracted reproducer found reproducer with 1 syscalls minimizing guilty program testing program (duration=45.868690468s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) program did not crash extracting C reproducer testing compiled C program (duration=45.868690468s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: stack segment fault in nsproxy_free a never seen crash title: stack segment fault in nsproxy_free, ignore simplifying guilty program options testing program (duration=45.868690468s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) (fail_nth: 2) program crashed: general protection fault in put_ipc_ns extracting C reproducer testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns simplifying C reproducer testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program did not crash testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns testing compiled C program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare program crashed: general protection fault in put_ipc_ns testing program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) (fail_nth: 2) program crashed: general protection fault in put_ipc_ns validation run: crashed=true testing program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) (fail_nth: 2) program crashed: general protection fault in put_ipc_ns validation run: crashed=true testing program (duration=45.868690468s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): unshare detailed listing: executing program 0: unshare(0x6a040000) (fail_nth: 2) program crashed: general protection fault in put_ipc_ns validation run: crashed=true reproducing took 19m44.919902307s repro crashed as (corrupted=false): RSP: 002b:00007fff968e5608 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fe58a3e5fa0 RCX: 00007fe58a18f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007fff968e5660 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fe58a3e5fa0 R14: 00007fe58a3e5fa0 R15: 0000000000000001 Oops: general protection fault, probably for non-canonical address 0xdffffc000000012f: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000978-0x000000000000097f] CPU: 1 UID: 0 PID: 6021 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:is_ns_init_id include/linux/ns_common.h:25 [inline] RIP: 0010:__ns_ref_dec_and_lock include/linux/ns_common.h:108 [inline] RIP: 0010:put_ipc_ns+0x7f/0x3d0 ipc/namespace.c:204 Code: b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 e8 08 6b 85 fd 48 85 db 0f 84 ea 00 00 00 4c 8d a3 88 09 00 00 4d 89 e6 49 c1 ee 03 <43> 80 3c 3e 00 74 08 4c 89 e7 e8 02 c4 eb fd 4d 8b 3c 24 31 ff 4c RSP: 0018:ffffc900034a7c60 EFLAGS: 00010203 RAX: ffffffff843c7548 RBX: fffffffffffffff4 RCX: ffff88805c080000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: fffffffffffffff4 RBP: ffffc900034a7cf8 R08: ffff8880325cd59f R09: 1ffff110064b9ab3 R10: dffffc0000000000 R11: ffffed10064b9ab4 R12: 000000000000097c R13: 1ffff92000694f8c R14: 000000000000012f R15: dffffc0000000000 FS: 0000555582176500(0000) GS:ffff888125b78000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555582176808 CR3: 00000000751d2000 CR4: 00000000003526f0 Call Trace: nsproxy_free+0x1ef/0x7c0 kernel/nsproxy.c:67 __free_nsproxy_free kernel/nsproxy.c:76 [inline] create_new_namespaces+0x47a/0x540 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:197 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3129 __do_sys_unshare kernel/fork.c:3200 [inline] __se_sys_unshare kernel/fork.c:3198 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3198 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe58a18f6c9 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:00007fff968e5608 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fe58a3e5fa0 RCX: 00007fe58a18f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007fff968e5660 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fe58a3e5fa0 R14: 00007fe58a3e5fa0 R15: 0000000000000001 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:is_ns_init_id include/linux/ns_common.h:25 [inline] RIP: 0010:__ns_ref_dec_and_lock include/linux/ns_common.h:108 [inline] RIP: 0010:put_ipc_ns+0x7f/0x3d0 ipc/namespace.c:204 Code: b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 e8 08 6b 85 fd 48 85 db 0f 84 ea 00 00 00 4c 8d a3 88 09 00 00 4d 89 e6 49 c1 ee 03 <43> 80 3c 3e 00 74 08 4c 89 e7 e8 02 c4 eb fd 4d 8b 3c 24 31 ff 4c RSP: 0018:ffffc900034a7c60 EFLAGS: 00010203 RAX: ffffffff843c7548 RBX: fffffffffffffff4 RCX: ffff88805c080000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: fffffffffffffff4 RBP: ffffc900034a7cf8 R08: ffff8880325cd59f R09: 1ffff110064b9ab3 R10: dffffc0000000000 R11: ffffed10064b9ab4 R12: 000000000000097c R13: 1ffff92000694f8c R14: 000000000000012f R15: dffffc0000000000 FS: 0000555582176500(0000) GS:ffff888125b78000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555582176808 CR3: 00000000751d2000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: b8 f1 f1 f1 f1 mov $0xf1f1f1f1,%eax 5: 00 f3 add %dh,%bl 7: f3 f3 4b 89 44 3d 00 repz xrelease mov %rax,0x0(%r13,%r15,1) e: e8 08 6b 85 fd call 0xfd856b1b 13: 48 85 db test %rbx,%rbx 16: 0f 84 ea 00 00 00 je 0x106 1c: 4c 8d a3 88 09 00 00 lea 0x988(%rbx),%r12 23: 4d 89 e6 mov %r12,%r14 26: 49 c1 ee 03 shr $0x3,%r14 * 2a: 43 80 3c 3e 00 cmpb $0x0,(%r14,%r15,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 e7 mov %r12,%rdi 34: e8 02 c4 eb fd call 0xfdebc43b 39: 4d 8b 3c 24 mov (%r12),%r15 3d: 31 ff xor %edi,%edi 3f: 4c rex.WR final repro crashed as (corrupted=false): RSP: 002b:00007fff968e5608 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fe58a3e5fa0 RCX: 00007fe58a18f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007fff968e5660 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fe58a3e5fa0 R14: 00007fe58a3e5fa0 R15: 0000000000000001 Oops: general protection fault, probably for non-canonical address 0xdffffc000000012f: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000978-0x000000000000097f] CPU: 1 UID: 0 PID: 6021 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:is_ns_init_id include/linux/ns_common.h:25 [inline] RIP: 0010:__ns_ref_dec_and_lock include/linux/ns_common.h:108 [inline] RIP: 0010:put_ipc_ns+0x7f/0x3d0 ipc/namespace.c:204 Code: b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 e8 08 6b 85 fd 48 85 db 0f 84 ea 00 00 00 4c 8d a3 88 09 00 00 4d 89 e6 49 c1 ee 03 <43> 80 3c 3e 00 74 08 4c 89 e7 e8 02 c4 eb fd 4d 8b 3c 24 31 ff 4c RSP: 0018:ffffc900034a7c60 EFLAGS: 00010203 RAX: ffffffff843c7548 RBX: fffffffffffffff4 RCX: ffff88805c080000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: fffffffffffffff4 RBP: ffffc900034a7cf8 R08: ffff8880325cd59f R09: 1ffff110064b9ab3 R10: dffffc0000000000 R11: ffffed10064b9ab4 R12: 000000000000097c R13: 1ffff92000694f8c R14: 000000000000012f R15: dffffc0000000000 FS: 0000555582176500(0000) GS:ffff888125b78000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555582176808 CR3: 00000000751d2000 CR4: 00000000003526f0 Call Trace: nsproxy_free+0x1ef/0x7c0 kernel/nsproxy.c:67 __free_nsproxy_free kernel/nsproxy.c:76 [inline] create_new_namespaces+0x47a/0x540 kernel/nsproxy.c:132 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:197 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3129 __do_sys_unshare kernel/fork.c:3200 [inline] __se_sys_unshare kernel/fork.c:3198 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3198 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe58a18f6c9 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:00007fff968e5608 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fe58a3e5fa0 RCX: 00007fe58a18f6c9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007fff968e5660 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007fe58a3e5fa0 R14: 00007fe58a3e5fa0 R15: 0000000000000001 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:is_ns_init_id include/linux/ns_common.h:25 [inline] RIP: 0010:__ns_ref_dec_and_lock include/linux/ns_common.h:108 [inline] RIP: 0010:put_ipc_ns+0x7f/0x3d0 ipc/namespace.c:204 Code: b8 f1 f1 f1 f1 00 f3 f3 f3 4b 89 44 3d 00 e8 08 6b 85 fd 48 85 db 0f 84 ea 00 00 00 4c 8d a3 88 09 00 00 4d 89 e6 49 c1 ee 03 <43> 80 3c 3e 00 74 08 4c 89 e7 e8 02 c4 eb fd 4d 8b 3c 24 31 ff 4c RSP: 0018:ffffc900034a7c60 EFLAGS: 00010203 RAX: ffffffff843c7548 RBX: fffffffffffffff4 RCX: ffff88805c080000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: fffffffffffffff4 RBP: ffffc900034a7cf8 R08: ffff8880325cd59f R09: 1ffff110064b9ab3 R10: dffffc0000000000 R11: ffffed10064b9ab4 R12: 000000000000097c R13: 1ffff92000694f8c R14: 000000000000012f R15: dffffc0000000000 FS: 0000555582176500(0000) GS:ffff888125b78000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000555582176808 CR3: 00000000751d2000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess): 0: b8 f1 f1 f1 f1 mov $0xf1f1f1f1,%eax 5: 00 f3 add %dh,%bl 7: f3 f3 4b 89 44 3d 00 repz xrelease mov %rax,0x0(%r13,%r15,1) e: e8 08 6b 85 fd call 0xfd856b1b 13: 48 85 db test %rbx,%rbx 16: 0f 84 ea 00 00 00 je 0x106 1c: 4c 8d a3 88 09 00 00 lea 0x988(%rbx),%r12 23: 4d 89 e6 mov %r12,%r14 26: 49 c1 ee 03 shr $0x3,%r14 * 2a: 43 80 3c 3e 00 cmpb $0x0,(%r14,%r15,1) <-- trapping instruction 2f: 74 08 je 0x39 31: 4c 89 e7 mov %r12,%rdi 34: e8 02 c4 eb fd call 0xfdebc43b 39: 4d 8b 3c 24 mov (%r12),%r15 3d: 31 ff xor %edi,%edi 3f: 4c rex.WR