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BUG: KASAN: slab-use-after-free in __xfrm_state_delete+0x696/0xca0
Write of size 8 at addr ffff888031cc0030 by task modprobe/8173

CPU: 0 UID: 0 PID: 8173 Comm: modprobe 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:___slab_alloc+0x4a2/0x1420
Code: 24 08 00 02 00 00 0f 84 c3 fb ff ff fb 89 dd e9 bb fb ff ff e8 7f 0d 63 09 f7 c3 00 02 00 00 0f 84 96 fe ff ff fb 8b 6c 24 20 <eb> 19 48 8b 74 24 20 48 c7 46 10 00 00 00 00 4c 8b 2c 24 4c 89 ef
RSP: 0018:ffffc90006a07330 EFLAGS: 00000206
RAX: a5000d0c63b28c00 RBX: 0000000000000246 RCX: a5000d0c63b28c00
RDX: 0000000000000006 RSI: ffffffff8d9ba64d RDI: ffffffff8be33f00
RBP: 00000000ffffffff R08: ffffffff8fa39237 R09: 1ffffffff1f47246
R10: dffffc0000000000 R11: fffffbfff1f47247 R12: 0000000000000000
R13: ffff88801a44bc80 R14: ffff88804b03f530 R15: ffff88804b03f550
 kmem_cache_alloc_noprof+0x283/0x3c0
 mas_alloc_nodes+0x2e9/0x8e0
 mas_store_gfp+0x46c/0x860
 do_vmi_align_munmap+0x2a7/0x420
 do_vmi_munmap+0x253/0x2e0
 __vm_munmap+0x23b/0x3d0
 elf_load+0x2c3/0x6c0
 load_elf_binary+0x1079/0x2740
 bprm_execve+0x99c/0x1450
 kernel_execve+0x8f0/0x9f0
 call_usermodehelper_exec_async+0x210/0x360
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 6047:
 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 9:
 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 ffff888031cc0000
 which belongs to the cache xfrm_state of size 928
The buggy address is located 48 bytes inside of
 freed 928-byte region [ffff888031cc0000, ffff888031cc03a0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888031cc1f80 pfn:0x31cc0
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 ffff888104cc1780 dead000000000122 0000000000000000
raw: ffff888031cc1f80 00000000800e0008 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff888104cc1780 dead000000000122 0000000000000000
head: ffff888031cc1f80 00000000800e0008 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000c73001 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 6047, tgid 6046 (syz.2.42), ts 70456160642, free_ts 70439984316
 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 5955 tgid 5954 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 stack_depot_save_flags+0x436/0x860
 kasan_save_track+0x4f/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 kmalloc_reserve+0xbd/0x290
 __alloc_skb+0x142/0x2d0
 inet6_ifmcaddr_notify+0xeb/0x1d0
 __ipv6_dev_mc_inc+0x8a9/0xa50
 ipv6_add_dev+0xe63/0x1370
 addrconf_notify+0x794/0x1010
 notifier_call_chain+0x1b6/0x3e0
 register_netdevice+0x1608/0x1ae0
 nsim_create+0xae8/0xf10
 __nsim_dev_port_add+0x6b6/0xb10
 nsim_dev_port_add_all+0x37/0xf0

Memory state around the buggy address:
 ffff888031cbff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888031cbff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888031cc0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888031cc0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888031cc0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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