L1TF CPU bug present and SMT on, data leak possible. See CVE-2018-3646 and https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/l1tf.html for details. ================================================================== BUG: KASAN: slab-out-of-bounds in search_memslots include/linux/kvm_host.h:1042 [inline] BUG: KASAN: slab-out-of-bounds in __gfn_to_memslot include/linux/kvm_host.h:1054 [inline] BUG: KASAN: slab-out-of-bounds in __kvm_gfn_to_hva_cache_init+0x53e/0x5f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2456 Read of size 8 at addr ffff888094a78468 by task syz-executor.3/8412 CPU: 1 PID: 8412 Comm: syz-executor.3 Not tainted 5.6.0-rc1-syzkaller #0 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+0x128/0x182 lib/dump_stack.c:118 print_address_description.constprop.8.cold.10+0x9/0x317 mm/kasan/report.c:374 __kasan_report.cold.11+0x1c/0x34 mm/kasan/report.c:506 kasan_report+0xe/0x20 mm/kasan/common.c:641 search_memslots include/linux/kvm_host.h:1042 [inline] __gfn_to_memslot include/linux/kvm_host.h:1054 [inline] __kvm_gfn_to_hva_cache_init+0x53e/0x5f0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2456 kvm_lapic_set_vapic_addr+0x72/0x140 arch/x86/kvm/lapic.c:2633 kvm_arch_vcpu_ioctl+0x1607/0x2980 arch/x86/kvm/x86.c:4353 kvm_vcpu_ioctl+0x1d0/0xa20 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3304 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0xb8/0x110 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770 do_syscall_64+0xc6/0x5e0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c849 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fd968201c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fd9682026d4 RCX: 000000000045c849 RDX: 0000000020000000 RSI: 000000004008ae93 RDI: 0000000000000005 RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000003dc R14: 00000000004c66f7 R15: 000000000076bf0c Allocated by task 8412: save_stack+0x19/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc.constprop.17+0xc1/0xd0 mm/kasan/common.c:515 kvmalloc include/linux/mm.h:645 [inline] kvzalloc include/linux/mm.h:653 [inline] kvm_dup_memslots arch/x86/kvm/../../../virt/kvm/kvm_main.c:1100 [inline] kvm_set_memslot+0xd4/0x1570 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1117 __kvm_set_memory_region+0x8fb/0xca0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1296 __x86_set_memory_region+0x1e0/0x420 arch/x86/kvm/x86.c:9756 alloc_apic_access_page arch/x86/kvm/vmx/vmx.c:3563 [inline] vmx_create_vcpu+0x1234/0x2190 arch/x86/kvm/vmx/vmx.c:6790 kvm_arch_vcpu_create+0x5f7/0x9e0 arch/x86/kvm/x86.c:9297 kvm_vm_ioctl_create_vcpu arch/x86/kvm/../../../virt/kvm/kvm_main.c:3043 [inline] kvm_vm_ioctl+0x1152/0x1f80 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3591 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0xb8/0x110 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x6a/0xb0 fs/ioctl.c:770 do_syscall_64+0xc6/0x5e0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 7013: save_stack+0x19/0x80 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0xf7/0x140 mm/kasan/common.c:476 __cache_free mm/slab.c:3426 [inline] kfree+0x107/0x2b0 mm/slab.c:3757 sk_prot_free net/core/sock.c:1640 [inline] __sk_destruct+0x470/0x640 net/core/sock.c:1724 sock_put include/net/sock.h:1719 [inline] pppoe_release+0x47f/0x590 drivers/net/ppp/pppoe.c:601 __sock_release+0xbb/0x270 net/socket.c:605 sock_close+0xf/0x20 net/socket.c:1283 __fput+0x256/0x780 fs/file_table.c:280 task_work_run+0x103/0x180 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x23d/0x2d0 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x4f8/0x5e0 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888094a78000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1128 bytes inside of 2048-byte region [ffff888094a78000, ffff888094a78800) The buggy address belongs to the page: page:ffffea0002529e00 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002a57f48 ffffea00028012c8 ffff8880aa400e00 raw: 0000000000000000 ffff888094a78000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888094a78300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888094a78380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888094a78400: 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc ^ ffff888094a78480: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888094a78500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================