[ OK ] Started OpenBSD Secure Shell server. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.243' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 29.204308] 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. [ 29.222874] FAULT_INJECTION: forcing a failure. [ 29.222874] name failslab, interval 1, probability 0, space 0, times 1 [ 29.234391] CPU: 1 PID: 8016 Comm: syz-executor358 Not tainted 4.14.285-syzkaller #0 [ 29.242258] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/18/2022 [ 29.251604] Call Trace: [ 29.254170] dump_stack+0x1b2/0x281 [ 29.257773] should_fail.cold+0x10a/0x149 [ 29.261899] should_failslab+0xd6/0x130 [ 29.265851] __kmalloc+0x2c1/0x400 [ 29.269365] ? kvm_io_bus_unregister_dev+0x116/0x320 [ 29.274444] kvm_io_bus_unregister_dev+0x116/0x320 [ 29.279348] ? lock_downgrade+0x740/0x740 [ 29.283469] kvm_vm_ioctl_unregister_coalesced_mmio+0x17d/0x280 [ 29.289517] kvm_vm_ioctl+0x601/0x13e0 [ 29.293383] ? kvm_vcpu_release+0xa0/0xa0 [ 29.297511] ? get_pid_task+0xb8/0x130 [ 29.301373] ? proc_fail_nth_write+0x7b/0x180 [ 29.305844] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.310753] ? fsnotify+0x974/0x11b0 [ 29.314441] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.319345] ? debug_check_no_obj_freed+0x2c0/0x680 [ 29.324354] ? kvm_vcpu_release+0xa0/0xa0 [ 29.328600] do_vfs_ioctl+0x75a/0xff0 [ 29.332388] ? ioctl_preallocate+0x1a0/0x1a0 [ 29.336788] ? vfs_write+0x319/0x4d0 [ 29.340488] ? SyS_write+0x14d/0x210 [ 29.344192] ? security_file_ioctl+0x83/0xb0 [ 29.348586] SyS_ioctl+0x7f/0xb0 [ 29.352384] ? do_vfs_ioctl+0xff0/0xff0 [ 29.356338] do_syscall_64+0x1d5/0x640 [ 29.360206] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.365370] RIP: 0033:0x7f0df7809739 [ 29.369053] RSP: 002b:00007ffd0d2e5d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 29.376738] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f0df7809739 [ 29.383991] RDX: 00000000200002c0 RSI: 000000004010ae68 RDI: 0000000000000004 [ 29.391239] RBP: 00007ffd0d2e5d70 R08: 0000000000000001 R09: 00007f0df77c0031 [ 29.398488] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 [ 29.405741] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.413515] kvm: failed to shrink bus, removing it completely [ 29.419785] ================================================================== [ 29.427265] BUG: KASAN: use-after-free in kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.435841] Read of size 8 at addr ffff8880b42cd580 by task syz-executor358/8016 [ 29.443350] [ 29.444961] CPU: 1 PID: 8016 Comm: syz-executor358 Not tainted 4.14.285-syzkaller #0 [ 29.452820] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/18/2022 [ 29.462151] Call Trace: [ 29.464719] dump_stack+0x1b2/0x281 [ 29.468327] print_address_description.cold+0x54/0x1d3 [ 29.473585] kasan_report_error.cold+0x8a/0x191 [ 29.478233] ? kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.484442] __asan_report_load8_noabort+0x68/0x70 [ 29.489351] ? kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.495563] ? kvm_vm_create_worker_thread+0x200/0x200 [ 29.500819] kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.506858] kvm_vm_ioctl+0x601/0x13e0 [ 29.510726] ? kvm_vcpu_release+0xa0/0xa0 [ 29.514852] ? get_pid_task+0xb8/0x130 [ 29.518718] ? proc_fail_nth_write+0x7b/0x180 [ 29.523189] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.528100] ? fsnotify+0x974/0x11b0 [ 29.531790] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.536712] ? debug_check_no_obj_freed+0x2c0/0x680 [ 29.541712] ? kvm_vcpu_release+0xa0/0xa0 [ 29.545843] do_vfs_ioctl+0x75a/0xff0 [ 29.549621] ? ioctl_preallocate+0x1a0/0x1a0 [ 29.554007] ? vfs_write+0x319/0x4d0 [ 29.557695] ? SyS_write+0x14d/0x210 [ 29.561386] ? security_file_ioctl+0x83/0xb0 [ 29.565801] SyS_ioctl+0x7f/0xb0 [ 29.569141] ? do_vfs_ioctl+0xff0/0xff0 [ 29.573102] do_syscall_64+0x1d5/0x640 [ 29.576972] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.582138] RIP: 0033:0x7f0df7809739 [ 29.585825] RSP: 002b:00007ffd0d2e5d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 29.593527] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f0df7809739 [ 29.600780] RDX: 00000000200002c0 RSI: 000000004010ae68 RDI: 0000000000000004 [ 29.608031] RBP: 00007ffd0d2e5d70 R08: 0000000000000001 R09: 00007f0df77c0031 [ 29.615287] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 [ 29.622543] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 29.629800] [ 29.631404] Allocated by task 8016: [ 29.635017] kasan_kmalloc+0xeb/0x160 [ 29.638810] kmem_cache_alloc_trace+0x131/0x3d0 [ 29.643458] kvm_vm_ioctl_register_coalesced_mmio+0x51/0x330 [ 29.649231] kvm_vm_ioctl+0xa81/0x13e0 [ 29.653097] do_vfs_ioctl+0x75a/0xff0 [ 29.656884] SyS_ioctl+0x7f/0xb0 [ 29.660250] do_syscall_64+0x1d5/0x640 [ 29.664116] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.669278] [ 29.670901] Freed by task 8016: [ 29.674171] kasan_slab_free+0xc3/0x1a0 [ 29.678121] kfree+0xc9/0x250 [ 29.681207] kvm_io_bus_unregister_dev.cold+0xd8/0xf8 [ 29.686375] kvm_vm_ioctl_unregister_coalesced_mmio+0x17d/0x280 [ 29.692422] kvm_vm_ioctl+0x601/0x13e0 [ 29.696289] do_vfs_ioctl+0x75a/0xff0 [ 29.700082] SyS_ioctl+0x7f/0xb0 [ 29.703430] do_syscall_64+0x1d5/0x640 [ 29.707296] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.712469] [ 29.714076] The buggy address belongs to the object at ffff8880b42cd580 [ 29.714076] which belongs to the cache kmalloc-64 of size 64 [ 29.726548] The buggy address is located 0 bytes inside of [ 29.726548] 64-byte region [ffff8880b42cd580, ffff8880b42cd5c0) [ 29.738138] The buggy address belongs to the page: [ 29.743063] page:ffffea0002d0b340 count:1 mapcount:0 mapping:ffff8880b42cd000 index:0x0 [ 29.751182] flags: 0xfff00000000100(slab) [ 29.755322] raw: 00fff00000000100 ffff8880b42cd000 0000000000000000 0000000100000020 [ 29.763179] raw: ffffea0002d11660 ffffea0002592aa0 ffff88813fe74340 0000000000000000 [ 29.771034] page dumped because: kasan: bad access detected [ 29.776717] [ 29.778317] Memory state around the buggy address: [ 29.783221] ffff8880b42cd480: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 29.790554] ffff8880b42cd500: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 29.797890] >ffff8880b42cd580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 29.805223] ^ [ 29.808577] ffff8880b42cd600: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 29.815911] ffff8880b42cd680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 29.823243] ================================================================== [ 29.830580] Disabling lock debugging due to kernel taint [ 29.836289] Kernel panic - not syncing: panic_on_warn set ... [ 29.836289] [ 29.843646] CPU: 1 PID: 8016 Comm: syz-executor358 Tainted: G B 4.14.285-syzkaller #0 [ 29.852734] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/18/2022 [ 29.862074] Call Trace: [ 29.864642] dump_stack+0x1b2/0x281 [ 29.868243] panic+0x1f9/0x42d [ 29.871409] ? add_taint.cold+0x16/0x16 [ 29.875359] ? ___preempt_schedule+0x16/0x18 [ 29.879753] kasan_end_report+0x43/0x49 [ 29.883718] kasan_report_error.cold+0xa7/0x191 [ 29.888363] ? kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.894570] __asan_report_load8_noabort+0x68/0x70 [ 29.899477] ? kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.905692] ? kvm_vm_create_worker_thread+0x200/0x200 [ 29.910948] kvm_vm_ioctl_unregister_coalesced_mmio+0x217/0x280 [ 29.916989] kvm_vm_ioctl+0x601/0x13e0 [ 29.920864] ? kvm_vcpu_release+0xa0/0xa0 [ 29.925087] ? get_pid_task+0xb8/0x130 [ 29.928951] ? proc_fail_nth_write+0x7b/0x180 [ 29.933425] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.938332] ? fsnotify+0x974/0x11b0 [ 29.942022] ? proc_tgid_io_accounting+0x7a0/0x7a0 [ 29.946928] ? debug_check_no_obj_freed+0x2c0/0x680 [ 29.951941] ? kvm_vcpu_release+0xa0/0xa0 [ 29.956080] do_vfs_ioctl+0x75a/0xff0 [ 29.959869] ? ioctl_preallocate+0x1a0/0x1a0 [ 29.964257] ? vfs_write+0x319/0x4d0 [ 29.967945] ? SyS_write+0x14d/0x210 [ 29.971633] ? security_file_ioctl+0x83/0xb0 [ 29.976012] SyS_ioctl+0x7f/0xb0 [ 29.979351] ? do_vfs_ioctl+0xff0/0xff0 [ 29.983313] do_syscall_64+0x1d5/0x640 [ 29.987177] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 29.992351] RIP: 0033:0x7f0df7809739 [ 29.996048] RSP: 002b:00007ffd0d2e5d68 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 30.003736] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f0df7809739 [ 30.010982] RDX: 00000000200002c0 RSI: 000000004010ae68 RDI: 0000000000000004 [ 30.018232] RBP: 00007ffd0d2e5d70 R08: 0000000000000001 R09: 00007f0df77c0031 [ 30.025489] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 [ 30.032738] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 30.040186] Kernel Offset: disabled [ 30.043794] Rebooting in 86400 seconds..