[ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty2. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.37' (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 syzkaller login: [ 75.061698][ T22] ================================================================== [ 75.069789][ T22] BUG: KFENCE: use-after-free read in kvm_fastop_exception+0xf6a/0x1058 [ 75.069789][ T22] [ 75.080311][ T22] Use-after-free read at 0xffff88823bd7e020 (in kfence-#190): [ 75.087758][ T22] kvm_fastop_exception+0xf6a/0x1058 [ 75.093070][ T22] d_lookup+0xd8/0x170 [ 75.097138][ T22] lookup_dcache+0x1e/0x130 [ 75.101644][ T22] __lookup_hash+0x29/0x180 [ 75.106150][ T22] kern_path_locked+0x17e/0x320 [ 75.111012][ T22] handle_remove+0xa2/0x5fe [ 75.115524][ T22] devtmpfsd+0x1b9/0x2a3 [ 75.119768][ T22] kthread+0x3e5/0x4d0 [ 75.125494][ T22] ret_from_fork+0x1f/0x30 [ 75.129917][ T22] [ 75.132228][ T22] kfence-#190: 0xffff88823bd7e000-0xffff88823bd7efff, size=4096, cache=names_cache [ 75.132228][ T22] [ 75.143666][ T22] allocated by task 22 on cpu 0 at 75.061659s: [ 75.149824][ T22] getname_kernel+0x4e/0x370 [ 75.154408][ T22] kern_path_locked+0x71/0x320 [ 75.159166][ T22] handle_remove+0xa2/0x5fe [ 75.163667][ T22] devtmpfsd+0x1b9/0x2a3 [ 75.168020][ T22] kthread+0x3e5/0x4d0 [ 75.172093][ T22] ret_from_fork+0x1f/0x30 [ 75.176512][ T22] [ 75.178829][ T22] freed by task 22 on cpu 0 at 75.061679s: [ 75.184659][ T22] putname.part.0+0xe1/0x120 [ 75.189243][ T22] kern_path_locked+0xc2/0x320 [ 75.194003][ T22] handle_remove+0xa2/0x5fe [ 75.198500][ T22] devtmpfsd+0x1b9/0x2a3 [ 75.202733][ T22] kthread+0x3e5/0x4d0 [ 75.206792][ T22] ret_from_fork+0x1f/0x30 [ 75.211199][ T22] [ 75.213508][ T22] CPU: 0 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-rc5-next-20210816-syzkaller #0 [ 75.222780][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 75.232824][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 75.238892][ T22] Code: d3 ed e9 f7 ae 6c f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 4d bc 6c 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 3d c6 6c f8 bd [ 75.258501][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 75.264556][ T22] RAX: 30317974746d7367 RBX: ffff88806c915068 RCX: ffff88823bd7e020 [ 75.272525][ T22] RDX: ffffed100d922a14 RSI: 0000000000000008 RDI: 0000000000000007 [ 75.280509][ T22] RBP: 0000000000000008 R08: 0000000000000000 R09: ffff88806c915098 [ 75.288559][ T22] R10: ffffed100d922a13 R11: 0000000000000000 R12: ffff88823bd7e020 [ 75.296523][ T22] R13: ffff88823bd7e020 R14: ffff88806c915098 R15: dffffc0000000000 [ 75.304490][ T22] FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 [ 75.313418][ T22] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 75.319997][ T22] CR2: ffff88823bd7e020 CR3: 000000006fc3b000 CR4: 00000000001506f0 [ 75.327976][ T22] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 75.335937][ T22] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 75.343899][ T22] Call Trace: [ 75.347176][ T22] d_lookup+0xd8/0x170 [ 75.351242][ T22] lookup_dcache+0x1e/0x130 [ 75.355750][ T22] __lookup_hash+0x29/0x180 [ 75.360257][ T22] kern_path_locked+0x17e/0x320 [ 75.365108][ T22] ? filename_lookup+0x80/0x80 [ 75.369870][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.375329][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.380787][ T22] handle_remove+0xa2/0x5fe [ 75.385288][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 75.390130][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 75.395778][ T22] ? finish_task_switch.isra.0+0x217/0xa20 [ 75.401596][ T22] ? trace_hardirqs_on+0x5b/0x1c0 [ 75.406618][ T22] ? finish_task_switch.isra.0+0x217/0xa20 [ 75.412418][ T22] ? __switch_to+0x5cc/0x1060 [ 75.417089][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.422549][ T22] ? lock_acquire+0x442/0x510 [ 75.427219][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.432679][ T22] ? lock_release+0x522/0x720 [ 75.437351][ T22] ? devtmpfsd+0xaa/0x2a3 [ 75.441676][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 75.446526][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 75.451546][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 75.456488][ T22] devtmpfsd+0x1b9/0x2a3 [ 75.460726][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 75.466268][ T22] kthread+0x3e5/0x4d0 [ 75.470332][ T22] ? set_kthread_struct+0x130/0x130 [ 75.475544][ T22] ret_from_fork+0x1f/0x30 [ 75.479962][ T22] ================================================================== [ 75.488009][ T22] Kernel panic - not syncing: panic_on_warn set ... [ 75.494577][ T22] CPU: 0 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-rc5-next-20210816-syzkaller #0 [ 75.503850][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 75.513906][ T22] Call Trace: [ 75.517183][ T22] dump_stack_lvl+0xcd/0x134 [ 75.521773][ T22] panic+0x2b0/0x6dd [ 75.525659][ T22] ? __warn_printk+0xf3/0xf3 [ 75.530245][ T22] ? kfence_report_error.cold+0x2f3/0xa56 [ 75.535966][ T22] kfence_report_error.cold+0x304/0xa56 [ 75.541596][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 75.547070][ T22] ? ret_from_fork+0x1f/0x30 [ 75.551655][ T22] ? kfence_print_object+0x2e0/0x2e0 [ 75.556938][ T22] ? deref_stack_reg+0x150/0x150 [ 75.561889][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 75.567347][ T22] ? d_lookup+0xd8/0x170 [ 75.571672][ T22] ? lookup_dcache+0x1e/0x130 [ 75.576344][ T22] ? __lookup_hash+0x29/0x180 [ 75.581015][ T22] ? kern_path_locked+0x17e/0x320 [ 75.586041][ T22] ? handle_remove+0xa2/0x5fe [ 75.590717][ T22] ? devtmpfsd+0x1b9/0x2a3 [ 75.595128][ T22] ? kthread+0x3e5/0x4d0 [ 75.599368][ T22] ? ret_from_fork+0x1f/0x30 [ 75.603972][ T22] ? unwind_next_frame+0x3da/0x1ce0 [ 75.609168][ T22] ? ret_from_fork+0x1f/0x30 [ 75.613760][ T22] kfence_handle_page_fault+0x2ed/0x670 [ 75.619318][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.624792][ T22] page_fault_oops+0x1c5/0x6b0 [ 75.629549][ T22] ? __sanitizer_cov_trace_const_cmp2+0x22/0x80 [ 75.635790][ T22] ? is_prefetch.constprop.0+0xb7/0x530 [ 75.641329][ T22] ? dump_pagetable+0xc0/0xc0 [ 75.646000][ T22] ? pgtable_bad+0x90/0x90 [ 75.650409][ T22] ? search_bpf_extables+0x1d1/0x2f0 [ 75.655686][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 75.661160][ T22] kernelmode_fixup_or_oops+0x219/0x280 [ 75.666712][ T22] __bad_area_nosemaphore+0x36d/0x400 [ 75.672165][ T22] ? spurious_kernel_fault+0x38d/0x5b0 [ 75.677794][ T22] do_kern_addr_fault+0x5b/0x70 [ 75.682648][ T22] exc_page_fault+0x155/0x180 [ 75.687319][ T22] asm_exc_page_fault+0x1e/0x30 [ 75.692176][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 75.698261][ T22] Code: d3 ed e9 f7 ae 6c f8 49 8d 0e 48 83 e1 f8 4c 8b 21 41 8d 0e 83 e1 07 c1 e1 03 49 d3 ec e9 4d bc 6c 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 3d c6 6c f8 bd [ 75.717861][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 75.723921][ T22] RAX: 30317974746d7367 RBX: ffff88806c915068 RCX: ffff88823bd7e020 [ 75.731886][ T22] RDX: ffffed100d922a14 RSI: 0000000000000008 RDI: 0000000000000007 [ 75.739849][ T22] RBP: 0000000000000008 R08: 0000000000000000 R09: ffff88806c915098 [ 75.747820][ T22] R10: ffffed100d922a13 R11: 0000000000000000 R12: ffff88823bd7e020 [ 75.755782][ T22] R13: ffff88823bd7e020 R14: ffff88806c915098 R15: dffffc0000000000 [ 75.763751][ T22] ? __d_lookup+0x372/0x720 [ 75.768256][ T22] d_lookup+0xd8/0x170 [ 75.772321][ T22] lookup_dcache+0x1e/0x130 [ 75.776824][ T22] __lookup_hash+0x29/0x180 [ 75.781335][ T22] kern_path_locked+0x17e/0x320 [ 75.786199][ T22] ? filename_lookup+0x80/0x80 [ 75.790982][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.796459][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.801922][ T22] handle_remove+0xa2/0x5fe [ 75.806443][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 75.811311][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 75.816961][ T22] ? finish_task_switch.isra.0+0x217/0xa20 [ 75.822760][ T22] ? trace_hardirqs_on+0x5b/0x1c0 [ 75.827783][ T22] ? finish_task_switch.isra.0+0x217/0xa20 [ 75.833593][ T22] ? __switch_to+0x5cc/0x1060 [ 75.838266][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.843723][ T22] ? lock_acquire+0x442/0x510 [ 75.848394][ T22] ? rcu_read_lock_sched_held+0xd/0x70 [ 75.853856][ T22] ? lock_release+0x522/0x720 [ 75.858526][ T22] ? devtmpfsd+0xaa/0x2a3 [ 75.862847][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 75.867691][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 75.872720][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 75.877653][ T22] devtmpfsd+0x1b9/0x2a3 [ 75.881891][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 75.887429][ T22] kthread+0x3e5/0x4d0 [ 75.891492][ T22] ? set_kthread_struct+0x130/0x130 [ 75.896691][ T22] ret_from_fork+0x1f/0x30 [ 75.902421][ T22] Kernel Offset: disabled [ 75.906742][ T22] Rebooting in 86400 seconds..