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BUG: KMSAN: kernel-infoleak in __copy_to_user include/linux/uaccess.h:121 [inline]
BUG: KMSAN: kernel-infoleak in __kvm_write_guest_page+0x2e1/0x490 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1855
CPU: 0 PID: 15363 Comm: syz-executor1 Not tainted 4.20.0-rc7+ #14
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+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 kmsan_internal_check_memory+0x9d4/0xb00 mm/kmsan/kmsan.c:704
 kmsan_copy_to_user+0xab/0xc0 mm/kmsan/kmsan_hooks.c:601
 __copy_to_user include/linux/uaccess.h:121 [inline]
 __kvm_write_guest_page+0x2e1/0x490 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1855
 kvm_vcpu_write_guest_page+0x5c8/0x600 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1876
 nested_release_vmcs12+0x2e2/0x490 arch/x86/kvm/vmx.c:8489
 handle_vmptrld+0x207c/0x2280 arch/x86/kvm/vmx.c:9328
 vmx_handle_exit+0x1582/0x9a00 arch/x86/kvm/vmx.c:10632
 vcpu_enter_guest arch/x86/kvm/x86.c:7811 [inline]
 vcpu_run arch/x86/kvm/x86.c:7874 [inline]
 kvm_arch_vcpu_ioctl_run+0xa5ad/0x11400 arch/x86/kvm/x86.c:8074
 kvm_vcpu_ioctl+0xfe9/0x1d20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2596
 do_vfs_ioctl+0xeeb/0x2c80 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x457759
Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f669d803c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457759
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000005
RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f669d8046d4
R13: 00000000004c06ba R14: 00000000004d1e30 R15: 00000000ffffffff

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmem_cache_alloc_trace+0x55a/0xb90 mm/slub.c:2789
 kmalloc include/linux/slab.h:546 [inline]
 enter_vmx_operation+0x104/0x1130 arch/x86/kvm/vmx.c:8315
 vmx_set_nested_state+0xdc5/0x18a0 arch/x86/kvm/vmx.c:14922
 kvm_arch_vcpu_ioctl+0x4a5e/0x7320 arch/x86/kvm/x86.c:4190
 kvm_vcpu_ioctl+0xc6d/0x1d20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2748
 do_vfs_ioctl+0xeeb/0x2c80 fs/ioctl.c:46
 ksys_ioctl fs/ioctl.c:713 [inline]
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl+0x1da/0x270 fs/ioctl.c:718
 __x64_sys_ioctl+0x4a/0x70 fs/ioctl.c:718
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Bytes 1000-4095 of 4096 are uninitialized
Memory access of size 4096 starts at ffff88817353b000
Data copied to user address 0000000020000000
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