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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff888123429b30 by task kworker/u8:2/5830

CPU: 1 UID: 0 PID: 5830 Comm: kworker/u8:2 Not tainted 6.16.0-syzkaller-06600-g1dbf1d590d10-dirty #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
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:free_tail_page_prepare+0x72/0x4f0
Code: 3c 28 00 74 08 48 89 df e8 ab e7 0d 00 48 c7 03 00 00 00 00 89 e8 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc <f3> 0f 1e fa 48 89 d8 48 89 3c 24 48 29 f8 48 c1 f8 06 48 83 f8 03
RSP: 0018:ffffc900031bf900 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffffea0000d04440 RCX: 0000000000000003
RDX: 0000000000000000 RSI: ffffea0000d04440 RDI: ffffea0000d04400
RBP: 0000000000000000 R08: ffffea0000d04407 R09: 1ffffd40001a0880
R10: dffffc0000000000 R11: fffff940001a0881 R12: ffffea0000d04400
R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000
 __free_frozen_pages+0x8aa/0xe70
 skb_release_data+0x62d/0x7c0
 consume_skb+0x9e/0xf0
 batadv_forw_packet_free+0x65/0x1f0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 9927:
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 xfrm_state_alloc+0x24/0x2f0
 __find_acq_core+0x8a7/0x1c00
 xfrm_find_acq+0x78/0xa0
 xfrm_alloc_userspi+0x6b3/0xc90
 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

Freed by task 5857:
 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 ffff888123429b00
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888123429b00, ffff888123429ea0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88812342ad00 pfn:0x123428
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff88801af7f8c0 dead000000000122 0000000000000000
raw: ffff88812342ad00 00000000800e0009 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801af7f8c0 dead000000000122 0000000000000000
head: ffff88812342ad00 00000000800e0009 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00048d0a01 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 5906, tgid 5901 (syz.2.4), ts 47545212048, free_ts 47494346575
 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
 __find_acq_core+0x8a7/0x1c00
 xfrm_find_acq+0x78/0xa0
 pfkey_getspi+0x65d/0xee0
 pfkey_sendmsg+0xbfe/0x1090
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
page last free pid 5900 tgid 5900 stack trace:
 __free_frozen_pages+0xc71/0xe70
 __put_partials+0x161/0x1c0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2f7/0x400
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 vm_area_dup+0x2b/0x680
 __split_vma+0x1a9/0xa00
 vma_modify+0x13b3/0x1970
 vma_modify_flags+0x1e8/0x230
 mprotect_fixup+0x400/0x9b0
 do_mprotect_pkey+0x8cd/0xce0
 __x64_sys_mprotect+0x80/0x90
 do_syscall_64+0xfa/0x3b0

Memory state around the buggy address:
 ffff888123429a00: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888123429a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888123429b00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888123429b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888123429c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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