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BUG: KASAN: use-after-free in xfrm_alloc_spi+0x570/0xf30
Read of size 4 at addr ffff8880288400c4 by task syz.0.2011/11120

CPU: 0 UID: 0 PID: 11120 Comm: syz.0.2011 Not tainted 6.17.0-rc1-syzkaller-00036-gdfc0f6373094-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 xfrm_alloc_spi+0x570/0xf30
 xfrm_alloc_userspi+0x70b/0xc90
 xfrm_user_rcv_msg+0x7a3/0xab0
 netlink_rcv_skb+0x208/0x470
 xfrm_netlink_rcv+0x79/0x90
 netlink_unicast+0x82f/0x9e0
 netlink_sendmsg+0x805/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbca178ebe9
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:00007fbca2525038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007fbca19b5fa0 RCX: 00007fbca178ebe9
RDX: 0000000000000000 RSI: 0000200000000540 RDI: 0000000000000003
RBP: 00007fbca1811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbca19b6038 R14: 00007fbca19b5fa0 R15: 00007ffe2dd0c508
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1fe pfn:0x28840
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f0(buddy)
raw: 00fff00000000000 ffffea00007a3908 ffffea0000e76d08 0000000000000000
raw: 00000000000001fe 0000000000000002 00000000f0000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x152c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 5947, tgid 5947 (udevd), ts 182121808257, free_ts 182180980350
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 alloc_pages_noprof+0xa9/0x190
 folio_alloc_noprof+0x1e/0x30
 filemap_alloc_folio_noprof+0xdf/0x470
 page_cache_ra_unbounded+0x2b9/0x7b0
 page_cache_sync_ra+0x3b9/0xb10
 filemap_get_pages+0x43c/0x1ea0
 filemap_read+0x3f6/0x11a0
 blkdev_read_iter+0x30a/0x440
 vfs_read+0x55a/0xa30
 ksys_read+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 8164 tgid 8164 stack trace:
 free_unref_folios+0xdbd/0x1520
 folios_put_refs+0x559/0x640
 mapping_try_invalidate+0x324/0x410
 ext4_put_super+0x813/0xc40
 generic_shutdown_super+0x135/0x2c0
 kill_block_super+0x44/0x90
 ext4_kill_sb+0x68/0xb0
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x425/0x4c0
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88802883ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888028840000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888028840080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                           ^
 ffff888028840100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888028840180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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