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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff888120924db0 by task syz-executor/5782

CPU: 1 UID: 0 PID: 5782 Comm: syz-executor 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
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
 do_softirq+0xec/0x180
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x17d/0x1c0
 __dev_queue_xmit+0x1d79/0x3b50
 ip_finish_output2+0xd03/0x1160
 ip_output+0x2a1/0x3c0
 __ip_queue_xmit+0x1106/0x1b00
 __tcp_transmit_skb+0x2215/0x3680
 tcp_write_xmit+0x1862/0x67f0
 tcp_sendmsg_locked+0x2b9f/0x5620
 tcp_sendmsg+0x2f/0x50
 __sock_sendmsg+0x19c/0x270
 sock_write_iter+0x258/0x330
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d1e38d620
Code: 40 00 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 80 3d 41 af 21 00 00 74 17 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 58 c3 0f 1f 80 00 00 00 00 48 83 ec 28 48 89
RSP: 002b:00007ffd1f92d538 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000035e1f200 RCX: 00007f4d1e38d620
RDX: 0000000000024560 RSI: 00007f4d18fdbaa0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000007 R09: 00000000003ffde8
R10: 68894afb159c4f48 R11: 0000000000000202 R12: 0000000000024560
R13: 000055555e576980 R14: 00007ffd1f92da00 R15: 00007f4d18fdbaa0
 </TASK>

Allocated by task 10342:
 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 24:
 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+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff888120924d80
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888120924d80, ffff888120925120)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888120924d80 pfn:0x120924
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 ffff88801c32cb40 dead000000000122 0000000000000000
raw: ffff888120924d80 00000000800e0007 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff88801c32cb40 dead000000000122 0000000000000000
head: ffff888120924d80 00000000800e0007 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea0004824901 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 6859, tgid 6858 (syz.2.255), ts 74652296739, free_ts 74583667701
 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/0x1420
 kmem_cache_alloc_noprof+0x283/0x3c0
 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
page last free pid 6853 tgid 6850 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 stack_depot_save_flags+0x436/0x860
 ref_tracker_alloc+0x18a/0x460
 ___neigh_create+0xc9e/0x2260
 ip6_finish_output2+0xb4d/0x16a0
 ip6_send_skb+0x1d5/0x390
 icmp6_send+0x12c6/0x1940
 ip6_link_failure+0x3b/0x4c0
 ip6_tnl_xmit+0xe08/0x2b10
 ip6_tnl_start_xmit+0xc1d/0x1150
 dev_hard_start_xmit+0x2d7/0x830
 __dev_queue_xmit+0x1b8d/0x3b50
 ip6_finish_output2+0x11fe/0x16a0
 ip6_fragment+0x1857/0x1e20
 ip6_send_skb+0x1d5/0x390
 ping_v6_sendmsg+0xf08/0x1210

Memory state around the buggy address:
 ffff888120924c80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888120924d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888120924d80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888120924e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888120924e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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