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BUG: KASAN: use-after-free in kvm_iodevice_destructor include/kvm/iodev.h:72 [inline]
BUG: KASAN: use-after-free in kvm_io_bus_destroy arch/x86/kvm/../../../virt/kvm/kvm_main.c:3401 [inline]
BUG: KASAN: use-after-free in kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:740 [inline]
BUG: KASAN: use-after-free in kvm_put_kvm+0xd7c/0xff0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:770
Read of size 8 at addr ffff8881d96f4510 by task syz-executor1/12059

CPU: 0 PID: 12059 Comm: syz-executor1 Not tainted 4.20.0-rc7+ #281
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:433
 kvm_iodevice_destructor include/kvm/iodev.h:72 [inline]
 kvm_io_bus_destroy arch/x86/kvm/../../../virt/kvm/kvm_main.c:3401 [inline]
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:740 [inline]
 kvm_put_kvm+0xd7c/0xff0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:770
 kvm_vm_release+0x42/0x50 arch/x86/kvm/../../../virt/kvm/kvm_main.c:781
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_32_irqs_on arch/x86/entry/common.c:341 [inline]
 do_fast_syscall_32+0xcd5/0xfb2 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139
RIP: 0023:0xf7f1da29
Code: 85 d2 74 02 89 0a 5b 5d c3 8b 04 24 c3 8b 14 24 c3 8b 3c 24 c3 90 90 90 90 90 90 90 90 90 90 90 90 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:000000000845fdac EFLAGS: 00000216 ORIG_RAX: 0000000000000006
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 12060:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620
 kmalloc include/linux/slab.h:546 [inline]
 kzalloc include/linux/slab.h:741 [inline]
 kvm_vm_ioctl_register_coalesced_mmio+0xe8/0x4f0 arch/x86/kvm/../../../virt/kvm/coalesced_mmio.c:147
 kvm_vm_ioctl+0x594/0x1d60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3014
 kvm_vm_compat_ioctl+0x143/0x430 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3178
 __do_compat_sys_ioctl fs/compat_ioctl.c:1052 [inline]
 __se_compat_sys_ioctl fs/compat_ioctl.c:998 [inline]
 __ia32_compat_sys_ioctl+0x20e/0x630 fs/compat_ioctl.c:998
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 12060:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3817
 coalesced_mmio_destructor+0x1ad/0x2a0 arch/x86/kvm/../../../virt/kvm/coalesced_mmio.c:99
 kvm_iodevice_destructor include/kvm/iodev.h:73 [inline]
 kvm_vm_ioctl_unregister_coalesced_mmio+0x263/0x330 arch/x86/kvm/../../../virt/kvm/coalesced_mmio.c:184
 kvm_vm_ioctl+0x6bc/0x1d60 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3023
 kvm_vm_compat_ioctl+0x143/0x430 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3178
 __do_compat_sys_ioctl fs/compat_ioctl.c:1052 [inline]
 __se_compat_sys_ioctl fs/compat_ioctl.c:998 [inline]
 __ia32_compat_sys_ioctl+0x20e/0x630 fs/compat_ioctl.c:998
 do_syscall_32_irqs_on arch/x86/entry/common.c:326 [inline]
 do_fast_syscall_32+0x34d/0xfb2 arch/x86/entry/common.c:397
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

The buggy address belongs to the object at ffff8881d96f4500
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 16 bytes inside of
 64-byte region [ffff8881d96f4500, ffff8881d96f4540)
The buggy address belongs to the page:
page:ffffea000765bd00 count:1 mapcount:0 mapping:ffff8881da800340 index:0x0
flags: 0x2fffc0000000200(slab)
raw: 02fffc0000000200 ffffea0006dd1a08 ffffea0006ded048 ffff8881da800340
raw: 0000000000000000 ffff8881d96f4000 0000000100000020 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8881d96f4400: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881d96f4480: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff8881d96f4500: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                         ^
 ffff8881d96f4580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8881d96f4600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
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