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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x666/0xca0
Write of size 8 at addr ffff88810fff0da8 by task kworker/u8:4/5896

CPU: 1 UID: 0 PID: 5896 Comm: kworker/u8:4 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: netns cleanup_net
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 __xfrm_state_delete+0x666/0xca0
 __xfrm_state_delete+0x87b/0xca0
 xfrm_state_flush+0x45f/0x770
 xfrm6_tunnel_net_exit+0x3c/0x100
 ops_undo_list+0x49a/0x990
 cleanup_net+0x4c5/0x800
 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 16475:
 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 5971:
 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 ffff88810fff0d80
 which belongs to the cache xfrm_state of size 928
The buggy address is located 40 bytes inside of
 freed 928-byte region [ffff88810fff0d80, ffff88810fff1120)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88810fff0480 pfn:0x10fff0
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 ffff888104bddc80 dead000000000122 0000000000000000
raw: ffff88810fff0480 00000000800e000d 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff888104bddc80 dead000000000122 0000000000000000
head: ffff88810fff0480 00000000800e000d 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00043ffc01 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 6726, tgid 6724 (syz.0.204), ts 90396600020, free_ts 90142086514
 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 51 tgid 51 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 free_large_kmalloc+0x13a/0x1f0
 device_release+0x9c/0x1c0
 kobject_put+0x22b/0x480
 usbhid_disconnect+0x9f/0xc0
 usb_unbind_interface+0x26e/0x910
 device_release_driver_internal+0x4d9/0x800
 bus_remove_device+0x34d/0x410
 device_del+0x511/0x8e0
 usb_disable_device+0x3e9/0x8a0
 usb_disconnect+0x330/0x950
 hub_event+0x1cf5/0x4a20
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770

Memory state around the buggy address:
 ffff88810fff0c80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88810fff0d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88810fff0d80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88810fff0e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810fff0e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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