[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ 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 '10.128.0.200' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 107.627925][ T22] ================================================================== [ 107.636000][ T22] BUG: KFENCE: use-after-free read in kvm_fastop_exception+0xf6a/0x1058 [ 107.636000][ T22] [ 107.646525][ T22] Use-after-free read at 0xffff88823bcf4020 (in kfence-#121): [ 107.653954][ T22] kvm_fastop_exception+0xf6a/0x1058 [ 107.659218][ T22] d_lookup+0xd8/0x170 [ 107.663264][ T22] lookup_dcache+0x1e/0x130 [ 107.667745][ T22] __lookup_hash+0x29/0x180 [ 107.672223][ T22] kern_path_locked+0x17e/0x320 [ 107.677053][ T22] handle_remove+0xa2/0x5fe [ 107.681542][ T22] devtmpfsd+0x1b9/0x2a3 [ 107.685760][ T22] kthread+0x3e5/0x4d0 [ 107.689808][ T22] ret_from_fork+0x1f/0x30 [ 107.694201][ T22] [ 107.696502][ T22] kfence-#121: 0xffff88823bcf4000-0xffff88823bcf4fff, size=4096, cache=names_cache [ 107.696502][ T22] [ 107.707938][ T22] allocated by task 22 on cpu 1 at 107.627724s: [ 107.714164][ T22] getname_kernel+0x4e/0x370 [ 107.718734][ T22] kern_path_locked+0x71/0x320 [ 107.723475][ T22] handle_remove+0xa2/0x5fe [ 107.727956][ T22] devtmpfsd+0x1b9/0x2a3 [ 107.732174][ T22] kthread+0x3e5/0x4d0 [ 107.736218][ T22] ret_from_fork+0x1f/0x30 [ 107.740613][ T22] [ 107.742911][ T22] freed by task 22 on cpu 1 at 107.627747s: [ 107.748806][ T22] putname.part.0+0xe1/0x120 [ 107.753371][ T22] kern_path_locked+0xc2/0x320 [ 107.758109][ T22] handle_remove+0xa2/0x5fe [ 107.762591][ T22] devtmpfsd+0x1b9/0x2a3 [ 107.766810][ T22] kthread+0x3e5/0x4d0 [ 107.770866][ T22] ret_from_fork+0x1f/0x30 [ 107.775256][ T22] [ 107.777557][ T22] CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0 [ 107.785254][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 107.795282][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 107.801326][ T22] Code: d3 ed e9 4f d9 6e f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 a5 e6 6e f8 49 8d 4d 00 48 83 e1 f8 <4c> 8b 21 41 8d 4d 00 83 e1 07 c1 e1 03 49 d3 ec e9 95 f0 6e f8 bd [ 107.820907][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 107.826952][ T22] RAX: 00003131706f6f6c RBX: ffff88806fe12c00 RCX: ffff88823bcf4020 [ 107.834905][ T22] RDX: ffffed100dfc2587 RSI: 0000000000000006 RDI: 0000000000000007 [ 107.842852][ T22] RBP: 0000000000000006 R08: 0000000000000000 R09: ffff88806fe12c30 [ 107.850800][ T22] R10: ffffed100dfc2586 R11: 0000000000000000 R12: ffff88823bcf4020 [ 107.858747][ T22] R13: ffff88823bcf4020 R14: ffff88806fe12c30 R15: dffffc0000000000 [ 107.866692][ T22] FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 [ 107.875604][ T22] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 107.882166][ T22] CR2: ffff88823bcf4020 CR3: 0000000073ef5000 CR4: 00000000001506e0 [ 107.890115][ T22] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 107.898060][ T22] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 107.906008][ T22] Call Trace: [ 107.909265][ T22] d_lookup+0xd8/0x170 [ 107.913316][ T22] lookup_dcache+0x1e/0x130 [ 107.917798][ T22] __lookup_hash+0x29/0x180 [ 107.922279][ T22] kern_path_locked+0x17e/0x320 [ 107.927112][ T22] ? filename_lookup+0x80/0x80 [ 107.931878][ T22] handle_remove+0xa2/0x5fe [ 107.936361][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 107.941984][ T22] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 107.947944][ T22] ? finish_task_switch.isra.0+0x232/0xa50 [ 107.953730][ T22] ? find_held_lock+0x2d/0x110 [ 107.958471][ T22] ? devtmpfsd+0xaa/0x2a3 [ 107.962778][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 107.967604][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 107.972607][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 107.977526][ T22] devtmpfsd+0x1b9/0x2a3 [ 107.981753][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 107.987280][ T22] kthread+0x3e5/0x4d0 [ 107.991335][ T22] ? set_kthread_struct+0x130/0x130 [ 107.996525][ T22] ret_from_fork+0x1f/0x30 [ 108.000923][ T22] ================================================================== [ 108.008954][ T22] Kernel panic - not syncing: panic_on_warn set ... [ 108.015882][ T22] CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0 [ 108.023579][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 108.033613][ T22] Call Trace: [ 108.036876][ T22] dump_stack_lvl+0xcd/0x134 [ 108.041460][ T22] panic+0x2b0/0x6dd [ 108.045338][ T22] ? __warn_printk+0xf3/0xf3 [ 108.049913][ T22] ? kfence_report_error.cold+0x2f3/0xa56 [ 108.055615][ T22] kfence_report_error.cold+0x304/0xa56 [ 108.061143][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 108.066584][ T22] ? kfence_print_object+0x2e0/0x2e0 [ 108.071853][ T22] ? add_lock_to_list.constprop.0+0x185/0x370 [ 108.077900][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 108.083337][ T22] ? d_lookup+0xd8/0x170 [ 108.087565][ T22] ? lookup_dcache+0x1e/0x130 [ 108.092225][ T22] ? __lookup_hash+0x29/0x180 [ 108.096883][ T22] ? kern_path_locked+0x17e/0x320 [ 108.101900][ T22] ? handle_remove+0xa2/0x5fe [ 108.106564][ T22] ? devtmpfsd+0x1b9/0x2a3 [ 108.110962][ T22] ? kthread+0x3e5/0x4d0 [ 108.115183][ T22] ? ret_from_fork+0x1f/0x30 [ 108.119776][ T22] ? mark_lock+0xef/0x17b0 [ 108.124179][ T22] kfence_handle_page_fault+0x203/0x630 [ 108.129714][ T22] page_fault_oops+0x1c5/0x6b0 [ 108.134462][ T22] ? __sanitizer_cov_trace_const_cmp2+0x22/0x80 [ 108.140686][ T22] ? is_prefetch.constprop.0+0xb7/0x530 [ 108.146215][ T22] ? dump_pagetable+0xc0/0xc0 [ 108.150883][ T22] ? pgtable_bad+0x90/0x90 [ 108.155280][ T22] ? search_bpf_extables+0x1d1/0x2f0 [ 108.160545][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 108.165998][ T22] kernelmode_fixup_or_oops+0x219/0x280 [ 108.171537][ T22] __bad_area_nosemaphore+0x36d/0x400 [ 108.176893][ T22] ? spurious_kernel_fault+0x38d/0x5b0 [ 108.182339][ T22] do_kern_addr_fault+0x5b/0x70 [ 108.187170][ T22] exc_page_fault+0x155/0x180 [ 108.191851][ T22] asm_exc_page_fault+0x1e/0x30 [ 108.196685][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 108.202736][ T22] Code: d3 ed e9 4f d9 6e f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 a5 e6 6e f8 49 8d 4d 00 48 83 e1 f8 <4c> 8b 21 41 8d 4d 00 83 e1 07 c1 e1 03 49 d3 ec e9 95 f0 6e f8 bd [ 108.222319][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 108.228364][ T22] RAX: 00003131706f6f6c RBX: ffff88806fe12c00 RCX: ffff88823bcf4020 [ 108.236311][ T22] RDX: ffffed100dfc2587 RSI: 0000000000000006 RDI: 0000000000000007 [ 108.244259][ T22] RBP: 0000000000000006 R08: 0000000000000000 R09: ffff88806fe12c30 [ 108.252219][ T22] R10: ffffed100dfc2586 R11: 0000000000000000 R12: ffff88823bcf4020 [ 108.260170][ T22] R13: ffff88823bcf4020 R14: ffff88806fe12c30 R15: dffffc0000000000 [ 108.268131][ T22] ? __d_lookup+0x372/0x720 [ 108.272624][ T22] d_lookup+0xd8/0x170 [ 108.276676][ T22] lookup_dcache+0x1e/0x130 [ 108.281166][ T22] __lookup_hash+0x29/0x180 [ 108.285652][ T22] kern_path_locked+0x17e/0x320 [ 108.290487][ T22] ? filename_lookup+0x80/0x80 [ 108.295238][ T22] handle_remove+0xa2/0x5fe [ 108.299739][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 108.305356][ T22] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 108.311317][ T22] ? finish_task_switch.isra.0+0x232/0xa50 [ 108.317199][ T22] ? find_held_lock+0x2d/0x110 [ 108.321952][ T22] ? devtmpfsd+0xaa/0x2a3 [ 108.326264][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 108.331107][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 108.336125][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 108.341054][ T22] devtmpfsd+0x1b9/0x2a3 [ 108.345276][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 108.350804][ T22] kthread+0x3e5/0x4d0 [ 108.354853][ T22] ? set_kthread_struct+0x130/0x130 [ 108.360035][ T22] ret_from_fork+0x1f/0x30 [ 108.364730][ T22] Kernel Offset: disabled [ 108.369343][ T22] Rebooting in 86400 seconds..