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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff888021809fb0 by task syz.1.1323/10952

CPU: 0 UID: 0 PID: 10952 Comm: syz.1.1323 Not tainted 6.16.0-syzkaller-06620-gae633388cae3 #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:
 <IRQ>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 __xfrm_state_delete+0x696/0xca0
 xfrm_timer_handler+0x18f/0xa00
 __hrtimer_run_queues+0x52c/0xc60
 hrtimer_run_softirq+0x187/0x2b0
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:shmem_add_to_page_cache+0xde/0xb10
Code: 89 df e8 75 5d 22 00 48 89 5c 24 08 48 8b 1b 48 89 de 48 83 e6 01 31 ff e8 4f 3f bf ff 48 83 e3 01 0f 85 22 09 00 00 4c 89 ef <be> 08 00 00 00 e8 b8 5f 22 00 4c 89 e8 48 c1 e8 03 48 89 44 24 10
RSP: 0018:ffffc90002a1f740 EFLAGS: 00000246
RAX: ffffffff82007641 RBX: 0000000000000000 RCX: ffff888122d30000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffea0000d089c0
RBP: ffffc90002a1f870 R08: 0000000000000cc0 R09: ffffffff822b78f9
R10: dffffc0000000000 R11: fffffbfff1f40f7f R12: 1ffff92000543ef4
R13: ffffea0000d089c0 R14: 0000000000000000 R15: dffffc0000000000
 shmem_alloc_and_add_folio+0x846/0xf60
 shmem_get_folio_gfp+0x59d/0x1660
 shmem_write_begin+0xf7/0x2b0
 generic_perform_write+0x2c5/0x900
 shmem_file_write_iter+0xf8/0x120
 vfs_write+0x54b/0xa90
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7bf2f8ebe9
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:00007f7bf3d6f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f7bf31b6090 RCX: 00007f7bf2f8ebe9
RDX: 0000000000806000 RSI: 0000200000000200 RDI: 0000000000000008
RBP: 00007f7bf3011e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7bf31b6128 R14: 00007f7bf31b6090 R15: 00007ffdfd734cf8
 </TASK>

Allocated by task 10764:
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 xfrm_state_alloc+0x24/0x2f0
 xfrm_add_sa+0x17d1/0x4070
 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

Freed by task 790:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x62/0x70
 kmem_cache_free+0x18f/0x400
 xfrm_state_gc_task+0x518/0x6a0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff888021809f80
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888021809f80, ffff88802180a320)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x21808
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff888104e1f140 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000e000e 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888104e1f140 dead000000000122 0000000000000000
head: 0000000000000000 00000000000e000e 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000860201 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5970, tgid 5969 (syz.2.19), ts 65083579371, free_ts 65047837594
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x3b0
 ___slab_alloc+0xbfc/0x1480
 kmem_cache_alloc_noprof+0x283/0x3c0
 xfrm_state_alloc+0x24/0x2f0
 xfrm_add_sa+0x17d1/0x4070
 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
page last free pid 5565 tgid 5565 stack trace:
 __free_frozen_pages+0xc71/0xe70
 __folio_put+0x21b/0x2c0
 free_large_kmalloc+0x145/0x200
 skb_release_data+0x62d/0x7c0
 consume_skb+0x9e/0xf0
 __unix_dgram_recvmsg+0x9f9/0xd60
 sock_recvmsg+0x22c/0x270
 sock_read_iter+0x231/0x2f0
 do_iter_readv_writev+0x56e/0x7f0
 vfs_readv+0x253/0x850
 do_readv+0x14d/0x2d0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888021809e80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888021809f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888021809f80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88802180a000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802180a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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