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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff888112b31230 by task kworker/u8:1/13

CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #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_nc_worker
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:lock_acquire+0xc9/0x360
Code: 03 11 85 c0 0f 85 eb 00 00 00 65 48 8b 04 25 08 80 a0 92 83 b8 ec 0a 00 00 00 0f 85 d5 00 00 00 48 c7 44 24 30 00 00 00 00 9c <8f> 44 24 30 4c 89 74 24 10 4d 89 fe 4c 8b 7c 24 30 fa 48 c7 c7 05
RSP: 0018:ffffc90000107908 EFLAGS: 00000246
RAX: ffff88801c688000 RBX: 0000000000000000 RCX: efa356818bfd7100
RDX: 0000000000000000 RSI: ffffffff8b47c54b RDI: 1ffffffff1c273e4
RBP: ffffffff8b47c52a R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: 0000000000000002
R13: ffffffff8e139f20 R14: 0000000000000000 R15: 0000000000000000
 batadv_nc_process_nc_paths+0xdb/0x3a0
 batadv_nc_worker+0x429/0x610
 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 15693:
 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 5883:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kmem_cache_free+0x18f/0x400
 xfrm_state_gc_task+0x52d/0x6b0
 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 ffff888112b31200
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888112b31200, ffff888112b315a0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888112b30000 pfn:0x112b30
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 ffff88801af46780 dead000000000122 0000000000000000
raw: ffff888112b30000 00000000800e000d 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801af46780 dead000000000122 0000000000000000
head: ffff888112b30000 00000000800e000d 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00044acc01 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 7712, tgid 7711 (syz.1.687), ts 124236003973, free_ts 124030036489
 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/0x370
 ___slab_alloc+0xbeb/0x1410
 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 7697 tgid 7695 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 stack_depot_save_flags+0x436/0x860
 kasan_save_track+0x4f/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 __ipv6_dev_mc_inc+0x44f/0xa50
 __ipv6_sock_mc_join+0x535/0x9c0
 ipv6_mcast_join_leave+0x177/0x1f0
 do_ipv6_setsockopt+0x17e8/0x2eb0
 ipv6_setsockopt+0x59/0x170
 do_sock_setsockopt+0x17c/0x1b0
 __x64_sys_setsockopt+0x13f/0x1b0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888112b31100: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888112b31180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888112b31200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888112b31280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888112b31300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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