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BUG: KASAN: slab-out-of-bounds in xfrm_policy_inexact_list_reinsert+0x599/0x650 net/xfrm/xfrm_policy.c:855
Read of size 1 at addr ffff8881e600bbd8 by task syz.4.834/2455

CPU: 1 PID: 2455 Comm: syz.4.834 Not tainted 5.4.289-syzkaller-00025-g49530c73f82d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
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
 xfrm_policy_inexact_list_reinsert+0x599/0x650 net/xfrm/xfrm_policy.c:855
 xfrm_policy_inexact_node_merge net/xfrm/xfrm_policy.c:987 [inline]
 xfrm_policy_inexact_insert_node+0x8f3/0xb00 net/xfrm/xfrm_policy.c:1043
 xfrm_policy_inexact_alloc_chain+0x4f9/0xb10 net/xfrm/xfrm_policy.c:1159
 xfrm_policy_inexact_insert+0x69/0x10e0 net/xfrm/xfrm_policy.c:1202
 xfrm_policy_insert+0xe1/0x8a0 net/xfrm/xfrm_policy.c:1585
 xfrm_add_policy+0x4f2/0x980 net/xfrm/xfrm_user.c:1720
 xfrm_user_rcv_msg+0x689/0x9b0 net/xfrm/xfrm_user.c:2775
 netlink_rcv_skb+0x1d5/0x420 net/netlink/af_netlink.c:2467
 xfrm_netlink_rcv+0x6e/0x80 net/xfrm/xfrm_user.c:2797
 netlink_unicast_kernel net/netlink/af_netlink.c:1306 [inline]
 netlink_unicast+0x936/0xb20 net/netlink/af_netlink.c:1332
 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 ____sys_sendmsg+0x5ac/0x8f0 net/socket.c:2306
 ___sys_sendmsg net/socket.c:2360 [inline]
 __sys_sendmsg+0x28b/0x380 net/socket.c:2406
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7efc4f3bdda9
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:00007efc4da28038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007efc4f5d6fa0 RCX: 00007efc4f3bdda9
RDX: 0000000000004000 RSI: 0000000020000580 RDI: 0000000000000005
RBP: 00007efc4f43f2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007efc4f5d6fa0 R15: 00007ffc990e1c98

Allocated by task 2455:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529
 kmalloc include/linux/slab.h:561 [inline]
 sk_prot_alloc+0xbd/0x3e0 net/core/sock.c:1622
 sk_alloc+0x35/0x2f0 net/core/sock.c:1680
 pfkey_create+0x122/0x670 net/key/af_key.c:154
 __sock_create+0x3cb/0x7a0 net/socket.c:1427
 sock_create net/socket.c:1478 [inline]
 __sys_socket+0x132/0x370 net/socket.c:1520
 __do_sys_socket net/socket.c:1529 [inline]
 __se_sys_socket net/socket.c:1527 [inline]
 __x64_sys_socket+0x76/0x80 net/socket.c:1527
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 352:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook mm/slub.c:1494 [inline]
 slab_free mm/slub.c:3080 [inline]
 kfree+0x123/0x370 mm/slub.c:4071
 skb_release_all net/core/skbuff.c:675 [inline]
 __kfree_skb net/core/skbuff.c:689 [inline]
 consume_skb+0xa5/0x2a0 net/core/skbuff.c:849
 netlink_unicast_kernel net/netlink/af_netlink.c:1307 [inline]
 netlink_unicast+0x93e/0xb20 net/netlink/af_netlink.c:1332
 netlink_sendmsg+0xa18/0xcf0 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:638 [inline]
 __sock_sendmsg net/socket.c:650 [inline]
 ____sys_sendmsg+0x5ac/0x8f0 net/socket.c:2306
 ___sys_sendmsg net/socket.c:2360 [inline]
 __sys_sendmsg+0x28b/0x380 net/socket.c:2406
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

The buggy address belongs to the object at ffff8881e600b800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 984 bytes inside of
 1024-byte region [ffff8881e600b800, ffff8881e600bc00)
The buggy address belongs to the page:
page:ffffea0007980200 refcount:1 mapcount:0 mapping:ffff8881f5c02280 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5c02280
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)
 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_slab_page+0x39/0x3c0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x97/0x440 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x2fe/0x490 mm/slub.c:2667
 __slab_alloc+0x62/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 __kmalloc+0x19b/0x2e0 mm/slub.c:3909
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kzalloc_node include/linux/slab.h:701 [inline]
 qdisc_alloc+0x78/0x7b0 net/sched/sch_generic.c:864
 qdisc_create_dflt+0x60/0x250 net/sched/sch_generic.c:937
 mq_init+0x2c8/0x6b0 net/sched/sch_mq.c:90
 qdisc_create_dflt+0x129/0x250 net/sched/sch_generic.c:944
 attach_default_qdiscs net/sched/sch_generic.c:1113 [inline]
 dev_activate+0x11f/0xc00 net/sched/sch_generic.c:1154
 __dev_open+0x302/0x420 net/core/dev.c:1335
 __dev_change_flags+0x1db/0x6e0 net/core/dev.c:7958
 dev_change_flags+0x87/0x190 net/core/dev.c:8029
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
 __free_slab+0x221/0x2e0 mm/slub.c:1774
 free_slab mm/slub.c:1789 [inline]
 discard_slab mm/slub.c:1795 [inline]
 unfreeze_partials+0x14e/0x180 mm/slub.c:2288
 put_cpu_partial+0x44/0x180 mm/slub.c:2324
 __slab_free+0x297/0x360 mm/slub.c:2971
 qlist_free_all+0x43/0xb0 mm/kasan/quarantine.c:167
 quarantine_reduce+0x1d9/0x210 mm/kasan/quarantine.c:260
 __kasan_kmalloc+0x41/0x210 mm/kasan/common.c:507
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842
 getname_flags+0xb8/0x4e0 fs/namei.c:141
 user_path_at_empty+0x28/0x50 fs/namei.c:2703
 user_path_at include/linux/namei.h:49 [inline]
 vfs_statx+0x115/0x210 fs/stat.c:187
 vfs_fstatat include/linux/fs.h:3387 [inline]
 __do_sys_newfstatat fs/stat.c:367 [inline]
 __se_sys_newfstatat+0xce/0x770 fs/stat.c:361
 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Memory state around the buggy address:
 ffff8881e600ba80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e600bb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881e600bb80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
                                                    ^
 ffff8881e600bc00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881e600bc80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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