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BUG: KASAN: slab-out-of-bounds in xfrm_policy_inexact_list_reinsert+0x606/0x6c0 net/xfrm/xfrm_policy.c:853
Read of size 1 at addr ffff8881269323d8 by task syz.4.574/2671

CPU: 1 PID: 2671 Comm: syz.4.574 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x1a7/0x208 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+0x606/0x6c0 net/xfrm/xfrm_policy.c:853
 xfrm_policy_inexact_node_merge net/xfrm/xfrm_policy.c:985 [inline]
 xfrm_policy_inexact_insert_node+0x938/0xb50 net/xfrm/xfrm_policy.c:1041
 xfrm_policy_inexact_alloc_chain+0x53d/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+0x4ed/0x850 net/xfrm/xfrm_user.c:1733
 xfrm_user_rcv_msg+0x4d0/0x7b0 net/xfrm/xfrm_user.c:2789
 netlink_rcv_skb+0x1f5/0x440 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+0x89c/0xb50 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2376
 ___sys_sendmsg+0x236/0x2e0 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+0x1f9/0x2c0 net/socket.c:2466
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7ff0eb582799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff0e9fdd028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ff0eb7fbfa0 RCX: 00007ff0eb582799
RDX: 0000000000000000 RSI: 0000200000000580 RDI: 0000000000000008
RBP: 00007ff0eb618c99 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ff0eb7fc038 R14: 00007ff0eb7fbfa0 R15: 00007ffc7d65a918

Allocated by task 2671:
 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+0x1a4/0x330 mm/slub.c:4038
 kmalloc include/linux/slab.h:560 [inline]
 sk_prot_alloc+0xb2/0x340 net/core/sock.c:1718
 sk_alloc+0x38/0x4e0 net/core/sock.c:1779
 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

The buggy address belongs to the object at ffff888126932000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 984 bytes inside of
 1024-byte region [ffff888126932000, ffff888126932400)
The buggy address belongs to the page:
page:ffffea00049a4c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x126930
head:ffffea00049a4c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 0000000000000000 0000000100000001 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 2323, ts 106755407317, free_ts 106691769986
 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+0x223b/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x290/0x620 mm/page_alloc.c:5384
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1813 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1874
 new_slab_objects mm/slub.c:2632 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2796
 __slab_alloc+0x63/0xa0 mm/slub.c:2836
 slab_alloc_node mm/slub.c:2918 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 __kmalloc_track_caller+0x1ec/0x320 mm/slub.c:4541
 __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
 netdev_queue_add_kobject net/core/net-sysfs.c:1660 [inline]
 netdev_queue_update_kobjects+0x1a7/0x390 net/core/net-sysfs.c:1694
 register_queue_kobjects net/core/net-sysfs.c:1755 [inline]
 netdev_register_kobject+0x2af/0x360 net/core/net-sysfs.c:2001
 register_netdevice+0xdf0/0x13e0 net/core/dev.c:10069
 veth_newlink+0x853/0xb60 drivers/net/veth.c:1387
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+0x80b/0x830 mm/page_alloc.c:1629
 free_the_page mm/page_alloc.c:5445 [inline]
 __free_pages+0xd8/0x3b0 mm/page_alloc.c:5454
 __free_slab+0xcf/0x190 mm/slub.c:1899
 free_slab mm/slub.c:1914 [inline]
 discard_slab mm/slub.c:1920 [inline]
 unfreeze_partials+0x15f/0x190 mm/slub.c:2415
 put_cpu_partial+0xc1/0x180 mm/slub.c:2451
 __slab_free+0x2c9/0x3a0 mm/slub.c:3100
 do_slab_free mm/slub.c:3196 [inline]
 ___cache_free+0x10e/0x130 mm/slub.c:3215
 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:580
 slab_alloc_node mm/slub.c:2952 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc+0x162/0x2d0 mm/slub.c:2965
 kmem_cache_alloc_node include/linux/slab.h:426 [inline]
 __alloc_skb+0x9e/0x520 net/core/skbuff.c:200
 alloc_skb include/linux/skbuff.h:1126 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1178 [inline]
 netlink_sendmsg+0x605/0xb50 net/netlink/af_netlink.c:1889
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 __sys_sendto+0x467/0x620 net/socket.c:2006

Memory state around the buggy address:
 ffff888126932280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888126932300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888126932380: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
                                                    ^
 ffff888126932400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888126932480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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