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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff88803ce396b0 by task syz.3.2175/14431

CPU: 1 UID: 0 PID: 14431 Comm: syz.3.2175 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
 __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:do_user_addr_fault+0xb91/0x1390
Code: 0f 84 d6 00 00 00 e8 5e dd 4b 00 48 8b 7c 24 48 48 81 c7 18 02 00 00 e8 cd 53 10 00 e9 c0 00 00 00 44 89 e6 81 e6 00 40 00 00 <31> ff e8 78 e1 4b 00 44 89 e0 25 00 40 00 00 0f 85 fa 02 00 00 0f
RSP: 0018:ffffc9000797f598 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000000002
RDX: ffff88810961b980 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff8881170fea80 R08: ffffffff8fa39037 R09: 1ffffffff1f47206
R10: dffffc0000000000 R11: fffffbfff1f47207 R12: 0000000000000000
R13: 0000200000601000 R14: 0000000000000000 R15: 0000000000000214
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0010:rep_movs_alternative+0x75/0x90
Code: 05 c3 cc cc cc cc 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01 c7 48 01 c6 48 29 c1 48 89 c8 48 c1 e9 03 83 e0 07 <f3> 48 a5 89 c1 85 c9 75 91 c3 cc cc cc cc 48 8d 0c c8 eb 86 cc cc
RSP: 0018:ffffc9000797f738 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8881320f8000 RCX: 0000000000000e28
RDX: 0000000000000001 RSI: 0000200000601000 RDI: ffff8881320f8ec0
RBP: ffffc9000797f8b0 R08: ffff8881320fffff R09: 1ffff1102641ffff
R10: dffffc0000000000 R11: ffffed1026420000 R12: 1ffff92000f2ff77
R13: 0000200000600140 R14: ffffc9000797fbc8 R15: 0000000000008000
 _copy_from_iter+0x24f/0x1790
 kcm_sendmsg+0xf00/0x2ad0
 __sock_sendmsg+0x21c/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: 0033:0x7f9f2978ebe9
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:00007f9f2a627038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f9f299c5fa0 RCX: 00007f9f2978ebe9
RDX: 00000000fffffdef RSI: 0000200000000140 RDI: 0000000000000006
RBP: 00007f9f29811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9f299c6038 R14: 00007f9f299c5fa0 R15: 00007ffd39ba9098
 </TASK>

Allocated by task 12768:
 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 10:
 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 ffff88803ce39680
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff88803ce39680, ffff88803ce39a20)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88803ce39680 pfn:0x3ce38
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 ffff888105472000 dead000000000122 0000000000000000
raw: ffff88803ce39680 00000000800e000c 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888105472000 dead000000000122 0000000000000000
head: ffff88803ce39680 00000000800e000c 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000f38e01 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 6258, tgid 6257 (syz.0.72), ts 63183950429, free_ts 0
 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
 __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_owner free stack trace missing

Memory state around the buggy address:
 ffff88803ce39580: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88803ce39600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803ce39680: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff88803ce39700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803ce39780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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