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BUG: KASAN: slab-out-of-bounds in hlist_add_head include/linux/list.h:814 [inline]
BUG: KASAN: slab-out-of-bounds in enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
Write of size 8 at addr ffff8881dab371c8 by task syz-executor/3003

CPU: 1 PID: 3003 Comm: syz-executor Not tainted 5.4.276-syzkaller-00021-g58de09405d1e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x241 lib/dump_stack.c:118
 print_address_description+0x8c/0x600 mm/kasan/report.c:384
 __kasan_report+0xf3/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 hlist_add_head include/linux/list.h:814 [inline]
 enqueue_timer+0xb7/0x300 kernel/time/timer.c:541
 __internal_add_timer kernel/time/timer.c:554 [inline]
 internal_add_timer+0x240/0x430 kernel/time/timer.c:604
 __mod_timer+0x6f1/0x13e0 kernel/time/timer.c:1065
 tun_flow_init drivers/net/tun.c:1446 [inline]
 tun_net_init+0x287/0x540 drivers/net/tun.c:1055
 register_netdevice+0x1c0/0x12a0 net/core/dev.c:9120
 tun_set_iff+0x7f7/0xdc0 drivers/net/tun.c:2919
 __tun_chr_ioctl+0x8a9/0x1d00 drivers/net/tun.c:3184
 do_vfs_ioctl+0x742/0x1720 fs/ioctl.c:47
 ksys_ioctl fs/ioctl.c:742 [inline]
 __do_sys_ioctl fs/ioctl.c:749 [inline]
 __se_sys_ioctl fs/ioctl.c:747 [inline]
 __x64_sys_ioctl+0xd4/0x110 fs/ioctl.c:747
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7f3274ac379b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007ffdd06a50e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f3274c51f20 RCX: 00007f3274ac379b
RDX: 00007ffdd06a5160 RSI: 00000000400454ca RDI: 00000000000000c8
RBP: 00007f3274c52a18 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000009

The buggy address belongs to the page:
page:ffffea00076acd00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 compound_mapcount: 0
flags: 0x8000000000010000(head)
raw: 8000000000010000 dead000000000100 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x140dc0(GFP_USER|__GFP_COMP|__GFP_ZERO)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x18f/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893
 __alloc_pages include/linux/gfp.h:503 [inline]
 __alloc_pages_node include/linux/gfp.h:516 [inline]
 alloc_pages_node include/linux/gfp.h:530 [inline]
 kmalloc_order mm/slab_common.c:1342 [inline]
 kmalloc_order_trace+0x2a/0x100 mm/slab_common.c:1358
 kmalloc_large include/linux/slab.h:485 [inline]
 kmalloc include/linux/slab.h:549 [inline]
 kzalloc include/linux/slab.h:690 [inline]
 tipc_nametbl_init+0x94/0x260 net/tipc/name_table.c:738
 tipc_init_net+0x22d/0x360 net/tipc/core.c:74
 ops_init+0x1d4/0x4a0 net/core/net_namespace.c:141
 setup_net+0x214/0x990 net/core/net_namespace.c:348
 copy_net_ns+0x30d/0x510 net/core/net_namespace.c:489
 create_new_namespaces+0x47a/0x570 kernel/nsproxy.c:103
 unshare_nsproxy_namespaces+0x119/0x170 kernel/nsproxy.c:202
 ksys_unshare+0x544/0x990 kernel/fork.c:2908
 __do_sys_unshare kernel/fork.c:2976 [inline]
 __se_sys_unshare kernel/fork.c:2974 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:2974
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x847/0x950 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4955 [inline]
 __free_pages+0x91/0x140 mm/page_alloc.c:4961
 bpf_check+0x8aaa/0xb340 kernel/bpf/verifier.c:9731
 bpf_prog_load kernel/bpf/syscall.c:1724 [inline]
 __do_sys_bpf kernel/bpf/syscall.c:2891 [inline]
 __se_sys_bpf+0x8139/0xbcb0 kernel/bpf/syscall.c:2849
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881dab37080: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff8881dab37100: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
>ffff8881dab37180: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
                                              ^
 ffff8881dab37200: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
 ffff8881dab37280: fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe fe
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