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BUG: KASAN: slab-out-of-bounds in __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
BUG: KASAN: slab-out-of-bounds in _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
Read of size 1 at addr ffff888053755a60 by task syz.0.195/6758

CPU: 3 UID: 0 PID: 6758 Comm: syz.0.195 Not tainted 6.16.0-rc2-syzkaller-00024-g9afe652958c3 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:408 [inline]
 print_report+0xcd/0x680 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 __kasan_check_byte+0x36/0x50 mm/kasan/common.c:557
 kasan_check_byte include/linux/kasan.h:399 [inline]
 lock_acquire kernel/locking/lockdep.c:5845 [inline]
 lock_acquire+0xfc/0x350 kernel/locking/lockdep.c:5828
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 futex_rehash_private kernel/futex/core.c:213 [inline]
 __futex_pivot_hash+0x1dd/0x540 kernel/futex/core.c:251
 futex_hash_allocate+0xad1/0xf00 kernel/futex/core.c:1662
 futex_hash_prctl+0x1f4/0x650 kernel/futex/core.c:1757
 __do_sys_prctl+0x171f/0x24c0 kernel/sys.c:2825
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f477838e929
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:00007f4779282038 EFLAGS: 00000246 ORIG_RAX: 000000000000009d
RAX: ffffffffffffffda RBX: 00007f47785b6160 RCX: 00007f477838e929
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000004e
RBP: 00007f4778410b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f47785b6160 R15: 00007ffc761171f8
 </TASK>

Allocated by task 6752:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4328 [inline]
 __kvmalloc_node_noprof+0x27b/0x620 mm/slub.c:5015
 futex_hash_allocate+0x49d/0xf00 kernel/futex/core.c:1601
 futex_hash_prctl+0x1f4/0x650 kernel/futex/core.c:1757
 __do_sys_prctl+0x171f/0x24c0 kernel/sys.c:2825
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888053755a00
 which belongs to the cache kmalloc-cg-64 of size 64
The buggy address is located 32 bytes to the right of
 allocated 64-byte region [ffff888053755a00, ffff888053755a40)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x53755
memcg:ffff888034bede01
ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88801b849a40 ffffea00014a4a80 0000000000000003
raw: 0000000000000000 0000000080200020 00000000f5000000 ffff888034bede01
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5948, tgid 5948 (syz-executor), ts 52019510808, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1704
 prep_new_page mm/page_alloc.c:1712 [inline]
 get_page_from_freelist+0x1321/0x3890 mm/page_alloc.c:3669
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:4959
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2419
 alloc_slab_page mm/slub.c:2451 [inline]
 allocate_slab mm/slub.c:2619 [inline]
 new_slab+0x23b/0x330 mm/slub.c:2673
 ___slab_alloc+0xd9c/0x1940 mm/slub.c:3859
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3949
 __slab_alloc_node mm/slub.c:4024 [inline]
 slab_alloc_node mm/slub.c:4185 [inline]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kvmalloc_node_noprof+0x3b1/0x620 mm/slub.c:5015
 alloc_netdev_mqs+0xfbe/0x1570 net/core/dev.c:11793
 vti6_init_net+0xf5/0x490 net/ipv6/ip6_vti.c:1146
 ops_init+0x1df/0x5f0 net/core/net_namespace.c:138
 setup_net+0x1ff/0x510 net/core/net_namespace.c:442
 copy_net_ns+0x2a6/0x5f0 net/core/net_namespace.c:574
 create_new_namespaces+0x3ea/0xa90 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:218
 ksys_unshare+0x45b/0xa40 kernel/fork.c:3121
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888053755900: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff888053755980: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
>ffff888053755a00: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                                       ^
 ffff888053755a80: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888053755b00: fa fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
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