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BUG: KASAN: slab-use-after-free in xfrm_state_find+0x2cf2/0x5400
Read of size 1 at addr ffff888126d8a2b0 by task syz.2.3941/21908

CPU: 0 UID: 0 PID: 21908 Comm: syz.2.3941 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_find+0x2cf2/0x5400
 xfrm_resolve_and_create_bundle+0x768/0x2f80
 xfrm_lookup_with_ifid+0x58a/0x1a70
 xfrm_lookup_route+0x3c/0x1c0
 igmpv3_newpack+0x27d/0x11d0
 add_grhead+0x70/0x340
 add_grec+0x1122/0x13e0
 igmp_ifc_timer_expire+0x978/0xde0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 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:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 cb 46 4b f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> 43 ef 13 f6 65 8b 05 0c 42 24 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc900042df880 EFLAGS: 00000206
RAX: d6e3900fa0580100 RBX: 0000000000000a02 RCX: d6e3900fa0580100
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: 0000000000000001
RBP: ffffc900042df910 R08: ffffffff8fa38337 R09: 1ffffffff1f47066
R10: dffffc0000000000 R11: fffffbfff1f47067 R12: dffffc0000000000
R13: ffff88810b5c9a68 R14: ffff8880321d6640 R15: 1ffff9200085bf10
 unix_stream_read_generic+0x15a4/0x2480
 unix_stream_recvmsg+0x15d/0x1b0
 sock_recvmsg+0x22c/0x270
 __sys_recvfrom+0x1f6/0x340
 __x64_sys_recvfrom+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd6a758ebe9
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:00007fd6a842a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002d
RAX: ffffffffffffffda RBX: 00007fd6a77b5fa0 RCX: 00007fd6a758ebe9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000007
RBP: 00007fd6a7611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000010102 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd6a77b6038 R14: 00007fd6a77b5fa0 R15: 00007ffd4f4cf378
 </TASK>

Allocated by task 16671:
 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+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff888126d89f80
 which belongs to the cache xfrm_state of size 928
The buggy address is located 816 bytes inside of
 freed 928-byte region [ffff888126d89f80, ffff888126d8a320)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888126d88d80 pfn:0x126d88
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 ffff888104a608c0 dead000000000122 0000000000000000
raw: ffff888126d88d80 00000000800e0003 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff888104a608c0 dead000000000122 0000000000000000
head: ffff888126d88d80 00000000800e0003 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea00049b6201 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 5958, tgid 5956 (syz.1.8), ts 47215337778, free_ts 47214588664
 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
 pfkey_add+0x6e4/0x2e00
 pfkey_sendmsg+0xbfe/0x1090
 __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
page last free pid 5957 tgid 5956 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 stack_depot_save_flags+0x436/0x860
 kasan_save_track+0x4f/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_node_noprof+0x276/0x4e0
 alloc_slab_obj_exts+0x39/0xa0
 __memcg_slab_post_alloc_hook+0x31e/0x7f0
 __kvmalloc_node_noprof+0x466/0x5f0
 bpf_check+0xf20/0x1d2d0
 bpf_prog_load+0x1318/0x1930
 __sys_bpf+0x528/0x870
 __x64_sys_bpf+0x7c/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888126d8a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888126d8a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888126d8a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888126d8a300: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888126d8a380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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