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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff8881235d5fb0 by task syz.1.3285/18799

CPU: 1 UID: 0 PID: 18799 Comm: syz.1.3285 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:irqentry_exit_to_user_mode+0x51/0x120
Code: 07 85 c0 0f 85 c3 00 00 00 e8 bb 5f 30 f6 65 4c 8b 34 25 08 60 a0 92 49 8b 3e f7 c7 1e 30 02 00 74 53 49 89 ff e8 af 5e 30 f6 <4c> 89 f8 a8 18 74 08 e8 63 1a 01 00 4c 89 f8 a9 00 10 00 00 74 0b
RSP: 0000:ffffc900092b7f38 EFLAGS: 00000286
RAX: 79da8b7e3da6e700 RBX: ffffc900092b7f58 RCX: 79da8b7e3da6e700
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff81aa3f25
RBP: 0000000000000000 R08: ffffffff8fa38437 R09: 1ffffffff1f47086
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88810bf5b980 R15: 0000000000000008
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0033:0x7f76e944d9f3
Code: 00 00 00 0f 1f 40 00 41 89 fb 44 8d 56 04 4c 8d 0d 22 46 35 00 89 f0 4c 8d 05 19 26 35 00 89 c2 81 e2 ff 1f 00 00 49 8b 0c d1 <48> 39 f1 74 28 48 85 c9 74 29 45 38 1c 10 75 23 83 c0 01 44 39 d0
RSP: 002b:00007ffe27082d48 EFLAGS: 00000206
RAX: 0000000081cea16a RBX: 00007f76ea2e5720 RCX: ffffffff81cea16a
RDX: 000000000000016a RSI: ffffffff81cea16a RDI: 0000000000000011
RBP: ffffffff81cea16a R08: 00007f76e97a0000 R09: 00007f76e97a2000
R10: 0000000081cea16e R11: 0000000000000011 R12: 0000000000000011
R13: 00000000000008c4 R14: ffffffff81cea16a R15: 0000000000019f6a
 </TASK>

Allocated by task 16569:
 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 6657:
 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 ffff8881235d5f80
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff8881235d5f80, ffff8881235d6320)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8881235d5f80 pfn:0x1235d4
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000240(workingset|head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000240 ffff88801cb58b40 ffff8881053884c8 ffffea00044ab110
raw: ffff8881235d5f80 00000000000e0001 00000000f5000000 0000000000000000
head: 057ff00000000240 ffff88801cb58b40 ffff8881053884c8 ffffea00044ab110
head: ffff8881235d5f80 00000000000e0001 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00048d7501 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 14160, tgid 14149 (syz.1.2119), ts 177831136619, free_ts 163183900820
 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_state_find+0x37d4/0x5400
 xfrm_resolve_and_create_bundle+0x768/0x2f80
 xfrm_lookup_with_ifid+0x2a7/0x1a70
 xfrm_lookup_route+0x3c/0x1c0
 udp_sendmsg+0x142e/0x2170
 __sock_sendmsg+0x19c/0x270
 ____sys_sendmsg+0x52d/0x830
 ___sys_sendmsg+0x21f/0x2a0
page last free pid 5845 tgid 5845 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __put_partials+0x156/0x1a0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2d5/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 dup_task_struct+0x52/0x860
 copy_process+0x54b/0x3c00
 kernel_clone+0x21e/0x840
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8881235d5e80: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881235d5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881235d5f80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff8881235d6000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881235d6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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