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BUG: KFENCE: use-after-free read in __xfrm_state_lookup+0x319/0x8d0

Use-after-free read at 0xffff888136542d42 (in kfence-#160):
 __xfrm_state_lookup+0x319/0x8d0
 xfrm_input_state_lookup+0x6e9/0xa60
 esp6_gro_receive+0x543/0xfe0
 xfrm6_gro_udp_encap_rcv+0x4bd/0x8e0
 udp_gro_receive+0x254b/0x25e0
 ipv6_gro_receive+0x1200/0x1640
 dev_gro_receive+0x183f/0x23b0
 napi_gro_frags+0x5e6/0x1030
 tun_get_user+0x28cb/0x3e20
 tun_chr_write_iter+0x113/0x200
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

kfence-#160: 0xffff888136542000-0xffff8881365420ff, size=256, cache=vm_area_struct

allocated by task 8803 on cpu 1 at 166.784210s (7.867992s ago):
 vm_area_alloc+0x24/0x140
 mmap_region+0xdc7/0x20c0
 do_mmap+0xc45/0x10d0
 vm_mmap_pgoff+0x2a6/0x4d0
 ksys_mmap_pgoff+0x51f/0x760
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

freed by task 8803 on cpu 1 at 166.784553s (7.885447s ago):
 vms_complete_munmap_vmas+0x626/0x8a0
 mmap_region+0x11db/0x20c0
 do_mmap+0xc45/0x10d0
 vm_mmap_pgoff+0x2a6/0x4d0
 ksys_mmap_pgoff+0x51f/0x760
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 9033 Comm: syz.2.445 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
RIP: 0010:__xfrm_state_lookup+0x319/0x8d0
Code: 30 48 89 4c 24 38 48 c1 e9 03 48 89 4c 24 50 4c 8d b3 42 01 00 00 4c 89 f0 48 c1 e8 03 42 0f b6 04 20 84 c0 0f 85 7c 03 00 00 <45> 0f b7 36 44 89 f7 44 89 ee e8 d8 d9 9e f7 66 45 39 ee 0f 85 2f
RSP: 0018:ffffc900067cf240 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888136542c00 RCX: 1ffff11021fc21cd
RDX: ffff8880262ed640 RSI: 000000000000000a RDI: 000000000000000a
RBP: ffffc900067cf330 R08: dffffc0000000000 R09: 0000000000000002
R10: 000000000000000a R11: 0000000000000002 R12: dffffc0000000000
R13: 000000000000000a R14: ffff888136542d42 R15: 0000000000000001
FS:  00007f1a177f66c0(0000) GS:ffff8881a3c15000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff888136542d42 CR3: 000000011ba30000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 xfrm_input_state_lookup+0x6e9/0xa60
 esp6_gro_receive+0x543/0xfe0
 xfrm6_gro_udp_encap_rcv+0x4bd/0x8e0
 udp_gro_receive+0x254b/0x25e0
 ipv6_gro_receive+0x1200/0x1640
 dev_gro_receive+0x183f/0x23b0
 napi_gro_frags+0x5e6/0x1030
 tun_get_user+0x28cb/0x3e20
 tun_chr_write_iter+0x113/0x200
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1a1958eba9
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:00007f1a177f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f1a197d5fa0 RCX: 00007f1a1958eba9
RDX: 00000000000000d6 RSI: 00002000000003c0 RDI: 0000000000000005
RBP: 00007f1a19611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1a197d6038 R14: 00007f1a197d5fa0 R15: 00007fff310a3da8
 </TASK>
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