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BUG: KASAN: slab-out-of-bounds in xfrm_policy_inexact_list_reinsert+0x620/0x6d0 net/xfrm/xfrm_policy.c:853
Read of size 1 at addr ffff88810bc2dbd8 by task syz.9.6438/19966

CPU: 0 PID: 19966 Comm: syz.9.6438 Not tainted 5.10.240-syzkaller-00225-g1154f779f3f3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report_generic.c:306
 xfrm_policy_inexact_list_reinsert+0x620/0x6d0 net/xfrm/xfrm_policy.c:853
 xfrm_policy_inexact_node_reinsert net/xfrm/xfrm_policy.c:941 [inline]
 xfrm_policy_inexact_node_merge net/xfrm/xfrm_policy.c:976 [inline]
 xfrm_policy_inexact_insert_node+0x5a7/0xb50 net/xfrm/xfrm_policy.c:1041
 xfrm_policy_inexact_alloc_chain+0x53a/0xb30 net/xfrm/xfrm_policy.c:1157
 xfrm_policy_inexact_insert+0x70/0x1130 net/xfrm/xfrm_policy.c:1200
 xfrm_policy_insert+0x126/0x9a0 net/xfrm/xfrm_policy.c:1586
 xfrm_add_policy+0x4d1/0x830 net/xfrm/xfrm_user.c:1733
 xfrm_user_rcv_msg+0x450/0x6d0 net/xfrm/xfrm_user.c:2789
 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503
 xfrm_netlink_rcv+0x72/0x90 net/xfrm/xfrm_user.c:2811
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2376
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2430
 __sys_sendmsg net/socket.c:2459 [inline]
 __do_sys_sendmsg net/socket.c:2468 [inline]
 __se_sys_sendmsg net/socket.c:2466 [inline]
 __x64_sys_sendmsg+0x1e2/0x2a0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f839d5059a9
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:00007f839bb6e038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f839d72cfa0 RCX: 00007f839d5059a9
RDX: 0000000000000000 RSI: 0000200000000580 RDI: 000000000000000b
RBP: 00007f839d587d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f839d72cfa0 R15: 00007ffebdf4a8b8

Allocated by task 19966:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc mm/kasan/common.c:509 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 __kmalloc+0x1a7/0x330 mm/slub.c:4033
 kmalloc include/linux/slab.h:557 [inline]
 sk_prot_alloc+0xb2/0x340 net/core/sock.c:1716
 sk_alloc+0x38/0x4e0 net/core/sock.c:1774
 pfkey_create+0x12a/0x660 net/key/af_key.c:154
 __sock_create+0x38d/0x770 net/socket.c:1436
 sock_create net/socket.c:1487 [inline]
 __sys_socket+0xec/0x190 net/socket.c:1529
 __do_sys_socket net/socket.c:1538 [inline]
 __se_sys_socket net/socket.c:1536 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1536
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 kvfree_call_rcu+0x10c/0x620 kernel/rcu/tree.c:3539
 drop_sysctl_table+0x2ef/0x410 fs/proc/proc_sysctl.c:1684
 unregister_sysctl_table+0x75/0x120 fs/proc/proc_sysctl.c:1722
 unregister_net_sysctl_table+0x15/0x20 net/sysctl_net.c:127
 neigh_sysctl_unregister+0x78/0x90 net/core/neighbour.c:3737
 addrconf_sysctl_unregister net/ipv6/addrconf.c:7121 [inline]
 addrconf_ifdown+0x1598/0x1800 net/ipv6/addrconf.c:3940
 addrconf_notify+0x3bd/0xe90 net/ipv6/addrconf.c:-1
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:410
 call_netdevice_notifiers_info net/core/dev.c:2054 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2066 [inline]
 call_netdevice_notifiers net/core/dev.c:2080 [inline]
 unregister_netdevice_many+0xf8b/0x1980 net/core/dev.c:10767
 default_device_exit_batch+0x330/0x390 net/core/dev.c:11287
 ops_exit_list net/core/net_namespace.c:190 [inline]
 cleanup_net+0x5fb/0xb70 net/core/net_namespace.c:609
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff88810bc2d800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 984 bytes inside of
 1024-byte region [ffff88810bc2d800, ffff88810bc2dc00)
The buggy address belongs to the page:
page:ffffea00042f0a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10bc28
head:ffffea00042f0a00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100042f00
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 8150, ts 359765471959, free_ts 359762054219
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5357
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 __kmalloc_track_caller+0x1ef/0x320 mm/slub.c:4536
 __kmalloc_reserve net/core/skbuff.c:144 [inline]
 __alloc_skb+0xdc/0x520 net/core/skbuff.c:212
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_uevent_skb+0x85/0x240 lib/kobject_uevent.c:290
 uevent_net_broadcast_tagged lib/kobject_uevent.c:351 [inline]
 kobject_uevent_net_broadcast+0x1a6/0x5a0 lib/kobject_uevent.c:412
 kobject_uevent_env+0x52e/0x700 lib/kobject_uevent.c:608
 kobject_uevent+0x1d/0x30 lib/kobject_uevent.c:657
 rx_queue_add_kobject net/core/net-sysfs.c:1029 [inline]
 net_rx_queue_update_kobjects+0x1ec/0x420 net/core/net-sysfs.c:1069
 register_queue_kobjects net/core/net-sysfs.c:1750 [inline]
 netdev_register_kobject+0x229/0x320 net/core/net-sysfs.c:2001
 register_netdevice+0xddd/0x13c0 net/core/dev.c:10056
 register_vlan_dev+0x2a0/0x5d0 net/8021q/vlan.c:177
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 __free_pages_ok+0x7fc/0x820 mm/page_alloc.c:1629
 free_the_page mm/page_alloc.c:5418 [inline]
 __free_pages+0xdd/0x380 mm/page_alloc.c:5427
 __free_slab+0xcf/0x190 mm/slub.c:1894
 free_slab mm/slub.c:1909 [inline]
 discard_slab mm/slub.c:1915 [inline]
 unfreeze_partials+0x15f/0x190 mm/slub.c:2410
 put_cpu_partial+0xc1/0x180 mm/slub.c:2446
 __slab_free+0x2c9/0x3a0 mm/slub.c:3095
 do_slab_free mm/slub.c:3191 [inline]
 ___cache_free+0x111/0x130 mm/slub.c:3210
 qlink_free+0x50/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:440
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:583
 slab_alloc_node mm/slub.c:2947 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 __kmalloc_track_caller+0x181/0x320 mm/slub.c:4536
 kvasprintf+0xd4/0x180 lib/kasprintf.c:25
 kvasprintf_const+0xf2/0x240 lib/kasprintf.c:49
 kobject_set_name_vargs+0x61/0x110 lib/kobject.c:297

Memory state around the buggy address:
 ffff88810bc2da80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88810bc2db00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88810bc2db80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                                    ^
 ffff88810bc2dc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88810bc2dc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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