[ 69.889122][ T22] ================================================================== [ 69.889134][ T22] BUG: KFENCE: use-after-free read in kvm_fastop_exception+0xf6a/0x1058 [ 69.889134][ T22] [ 69.889187][ T22] Use-after-free read at 0xffff88823bdba020 (in kfence-#220): [ 69.889202][ T22] kvm_fastop_exception+0xf6a/0x1058 [ 69.889225][ T22] d_lookup+0xd8/0x170 [ 69.889249][ T22] lookup_dcache+0x1e/0x130 [ 69.889280][ T22] __lookup_hash+0x29/0x180 [ 69.889302][ T22] kern_path_locked+0x17e/0x320 [ 69.889328][ T22] handle_remove+0xa2/0x5fe [ 69.889354][ T22] devtmpfsd+0x1b9/0x2a3 [ 69.889376][ T22] kthread+0x3e5/0x4d0 [ 69.889400][ T22] ret_from_fork+0x1f/0x30 [ 69.889423][ T22] [ 69.889428][ T22] kfence-#220 [0xffff88823bdba000-0xffff88823bdbafff, size=4096, cache=names_cache] allocated by task 22: [ 69.889472][ T22] getname_kernel+0x4e/0x370 [ 69.889496][ T22] kern_path_locked+0x71/0x320 [ 69.889521][ T22] handle_remove+0xa2/0x5fe [ 69.889545][ T22] devtmpfsd+0x1b9/0x2a3 [ 69.889565][ T22] kthread+0x3e5/0x4d0 [ 69.889587][ T22] ret_from_fork+0x1f/0x30 [ 69.889609][ T22] [ 69.889609][ T22] freed by task 22: [ 69.889638][ T22] putname.part.0+0xe1/0x120 [ 69.889660][ T22] kern_path_locked+0xc2/0x320 [ 69.889685][ T22] handle_remove+0xa2/0x5fe [ 69.889709][ T22] devtmpfsd+0x1b9/0x2a3 [ 69.889730][ T22] kthread+0x3e5/0x4d0 [ 69.889752][ T22] ret_from_fork+0x1f/0x30 [ 69.889772][ T22] [ 69.889777][ T22] CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0 [ 69.889801][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.889814][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 69.889839][ T22] Code: d3 ed e9 ef d4 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 45 e2 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 35 ec 6e f8 bd [ 69.889860][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 69.889880][ T22] RAX: 0000000034736376 RBX: ffff88806fd58c00 RCX: ffff88823bdba020 [ 69.889897][ T22] RDX: ffffed100dfab187 RSI: 0000000000000004 RDI: 0000000000000007 [ 69.889913][ T22] RBP: 0000000000000004 R08: 0000000000000000 R09: ffff88806fd58c30 [ 69.889928][ T22] R10: ffffed100dfab186 R11: 0000000000000000 R12: ffff88823bdba020 [ 69.889944][ T22] R13: ffff88823bdba020 R14: ffff88806fd58c30 R15: dffffc0000000000 [ 69.889961][ T22] FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 [ 69.889985][ T22] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 69.890002][ T22] CR2: ffff88823bdba020 CR3: 000000007291e000 CR4: 00000000001506e0 [ 69.890018][ T22] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 69.890033][ T22] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 69.890048][ T22] Call Trace: [ 69.890061][ T22] d_lookup+0xd8/0x170 [ 69.890088][ T22] lookup_dcache+0x1e/0x130 [ 69.890114][ T22] __lookup_hash+0x29/0x180 [ 69.890141][ T22] kern_path_locked+0x17e/0x320 [ 69.890169][ T22] ? filename_lookup+0x80/0x80 [ 69.890203][ T22] handle_remove+0xa2/0x5fe [ 69.890231][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 69.890263][ T22] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 69.890296][ T22] ? finish_task_switch.isra.0+0x232/0xa50 [ 69.890327][ T22] ? find_held_lock+0x2d/0x110 [ 69.890350][ T22] ? devtmpfsd+0xaa/0x2a3 [ 69.890373][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 69.890395][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 69.890421][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 69.890449][ T22] devtmpfsd+0x1b9/0x2a3 [ 69.890474][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 69.890501][ T22] kthread+0x3e5/0x4d0 [ 69.890526][ T22] ? set_kthread_struct+0x130/0x130 [ 69.890555][ T22] ret_from_fork+0x1f/0x30 [ 69.890587][ T22] ================================================================== [ 69.890598][ T22] Kernel panic - not syncing: panic_on_warn set ... [ 69.890878][ T22] CPU: 1 PID: 22 Comm: kdevtmpfs Not tainted 5.14.0-syzkaller #0 [ 69.890903][ T22] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.890918][ T22] Call Trace: [ 69.890926][ T22] dump_stack_lvl+0xcd/0x134 [ 69.890954][ T22] panic+0x2b0/0x6dd [ 69.890977][ T22] ? __warn_printk+0xf3/0xf3 [ 69.891014][ T22] ? kfence_report_error.cold+0x2f3/0xa56 [ 69.891049][ T22] kfence_report_error.cold+0x304/0xa56 [ 69.891079][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 69.891110][ T22] ? kfence_print_object+0x350/0x350 [ 69.891143][ T22] ? add_lock_to_list.constprop.0+0x185/0x370 [ 69.891171][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 69.891195][ T22] ? d_lookup+0xd8/0x170 [ 69.891221][ T22] ? lookup_dcache+0x1e/0x130 [ 69.891247][ T22] ? __lookup_hash+0x29/0x180 [ 69.891281][ T22] ? kern_path_locked+0x17e/0x320 [ 69.891310][ T22] ? handle_remove+0xa2/0x5fe [ 69.891339][ T22] ? devtmpfsd+0x1b9/0x2a3 [ 69.891364][ T22] ? kthread+0x3e5/0x4d0 [ 69.891390][ T22] ? ret_from_fork+0x1f/0x30 [ 69.891465][ T22] ? mark_lock+0xef/0x17b0 [ 69.891507][ T22] kfence_handle_page_fault+0x203/0x630 [ 69.891544][ T22] page_fault_oops+0x1c5/0x6b0 [ 69.891571][ T22] ? __sanitizer_cov_trace_const_cmp2+0x22/0x80 [ 69.891600][ T22] ? is_prefetch.constprop.0+0xb7/0x530 [ 69.891627][ T22] ? dump_pagetable+0xc0/0xc0 [ 69.891654][ T22] ? pgtable_bad+0x90/0x90 [ 69.891684][ T22] ? search_bpf_extables+0x1d1/0x2f0 [ 69.891709][ T22] ? kvm_fastop_exception+0xf6a/0x1058 [ 69.891744][ T22] kernelmode_fixup_or_oops+0x219/0x280 [ 69.891774][ T22] __bad_area_nosemaphore+0x36d/0x400 [ 69.891802][ T22] ? spurious_kernel_fault+0x38d/0x5b0 [ 69.891834][ T22] do_kern_addr_fault+0x5b/0x70 [ 69.891862][ T22] exc_page_fault+0x155/0x180 [ 69.891891][ T22] asm_exc_page_fault+0x1e/0x30 [ 69.891919][ T22] RIP: 0010:kvm_fastop_exception+0xf6a/0x1058 [ 69.891947][ T22] Code: d3 ed e9 ef d4 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 45 e2 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 35 ec 6e f8 bd [ 69.891970][ T22] RSP: 0018:ffffc90000dcfae8 EFLAGS: 00010282 [ 69.891992][ T22] RAX: 0000000034736376 RBX: ffff88806fd58c00 RCX: ffff88823bdba020 [ 69.892009][ T22] RDX: ffffed100dfab187 RSI: 0000000000000004 RDI: 0000000000000007 [ 69.892025][ T22] RBP: 0000000000000004 R08: 0000000000000000 R09: ffff88806fd58c30 [ 69.892040][ T22] R10: ffffed100dfab186 R11: 0000000000000000 R12: ffff88823bdba020 [ 69.892056][ T22] R13: ffff88823bdba020 R14: ffff88806fd58c30 R15: dffffc0000000000 [ 69.892093][ T22] ? __d_lookup+0x372/0x720 [ 69.892134][ T22] d_lookup+0xd8/0x170 [ 69.892165][ T22] lookup_dcache+0x1e/0x130 [ 69.892195][ T22] __lookup_hash+0x29/0x180 [ 69.892227][ T22] kern_path_locked+0x17e/0x320 [ 69.892259][ T22] ? filename_lookup+0x80/0x80 [ 69.892311][ T22] handle_remove+0xa2/0x5fe [ 69.892346][ T22] ? cacheinfo_cpu_online.cold+0x3e/0x3e [ 69.892383][ T22] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 69.892413][ T22] ? finish_task_switch.isra.0+0x232/0xa50 [ 69.892455][ T22] ? find_held_lock+0x2d/0x110 [ 69.892484][ T22] ? devtmpfsd+0xaa/0x2a3 [ 69.892511][ T22] ? lock_downgrade+0x6e0/0x6e0 [ 69.892539][ T22] ? do_raw_spin_lock+0x120/0x2b0 [ 69.892569][ T22] ? rwlock_bug.part.0+0x90/0x90 [ 69.892609][ T22] devtmpfsd+0x1b9/0x2a3 [ 69.892640][ T22] ? dmar_validate_one_drhd+0x24d/0x24d [ 69.892673][ T22] kthread+0x3e5/0x4d0 [ 69.892701][ T22] ? set_kthread_struct+0x130/0x130 [ 69.892735][ T22] ret_from_fork+0x1f/0x30 [ 69.892958][ T22] Kernel Offset: disabled [ 70.637945][ T22] Rebooting in 86400 seconds..