[ 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 '10.128.15.200' (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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program 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: [ 76.025657][ T21] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN [ 76.037387][ T21] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 76.045815][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.9.0-rc6-syzkaller #0 [ 76.054839][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 76.064892][ T21] Workqueue: writeback wb_workfn (flush-8:0) [ 76.070867][ T21] RIP: 0010:__ext4_journal_get_write_access+0x6b/0x2b0 [ 76.077704][ T21] Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 25 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 30 48 8d 7b 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 f8 01 00 00 4c 8b 73 10 4d 85 f6 0f 84 f4 00 00 [ 76.097298][ T21] RSP: 0018:ffffc90000dd6db8 EFLAGS: 00010202 [ 76.104205][ T21] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a4b83740 [ 76.113037][ T21] RDX: 0000000000000002 RSI: ffffffff8a067e40 RDI: 0000000000000010 [ 76.121025][ T21] RBP: ffff8880a4b83740 R08: 0000000000000001 R09: ffff8880a900ee60 [ 76.129010][ T21] R10: fffffbfff16b2399 R11: 0000000000000000 R12: 0000000000000001 [ 76.136973][ T21] R13: 1ffff920001badcb R14: ffff888214b28000 R15: 0000000000000c9d [ 76.144940][ T21] FS: 0000000000000000(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 [ 76.153880][ T21] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 76.160452][ T21] CR2: 000000000046b410 CR3: 0000000096834000 CR4: 00000000001506e0 [ 76.168420][ T21] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 76.176381][ T21] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 76.184342][ T21] Call Trace: [ 76.187627][ T21] ? ext4_get_group_desc+0x297/0x4e0 [ 76.192912][ T21] ext4_mb_mark_diskspace_used+0x299/0x1130 [ 76.198804][ T21] ? ext4_mb_try_best_found.isra.0+0x9e0/0x9e0 [ 76.204973][ T21] ? kmem_cache_alloc+0x354/0x3f0 [ 76.209994][ T21] ext4_mb_new_blocks+0xbea/0x4720 [ 76.215136][ T21] ? ext4_ext_search_right+0x2ca/0xb30 [ 76.220587][ T21] ? ext4_inode_to_goal_block+0x2d2/0x3e0 [ 76.226303][ T21] ext4_ext_map_blocks+0x2320/0x61b0 [ 76.231595][ T21] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 76.237571][ T21] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 76.243544][ T21] ? ext4_ext_release+0x10/0x10 [ 76.248387][ T21] ? lock_acquire+0x1f3/0xaf0 [ 76.253059][ T21] ? ext4_map_blocks+0x746/0x1650 [ 76.258076][ T21] ? find_held_lock+0x2d/0x110 [ 76.262833][ T21] ? lock_release+0x8f0/0x8f0 [ 76.267504][ T21] ? ext4_es_lookup_extent+0x3b1/0xce0 [ 76.272956][ T21] ? lock_is_held_type+0xbb/0xf0 [ 76.277890][ T21] ? down_write_killable+0x170/0x170 [ 76.283168][ T21] ? rcu_read_lock_sched_held+0x3a/0xb0 [ 76.288707][ T21] ? ext4_es_lookup_extent+0x41d/0xce0 [ 76.294159][ T21] ext4_map_blocks+0x7b8/0x1650 [ 76.299008][ T21] ? lock_is_held_type+0xbb/0xf0 [ 76.303935][ T21] ? ext4_issue_zeroout+0x1e0/0x1e0 [ 76.309125][ T21] ? rcu_read_lock_sched_held+0x3a/0xb0 [ 76.314663][ T21] ? kmem_cache_alloc+0x354/0x3f0 [ 76.319682][ T21] ? lock_is_held_type+0xbb/0xf0 [ 76.324614][ T21] ext4_writepages+0x1c4c/0x3960 [ 76.329555][ T21] ? mark_lock+0x82/0x1660 [ 76.333972][ T21] ? mark_held_locks+0x9f/0xe0 [ 76.338728][ T21] ? check_preemption_disabled+0x50/0x130 [ 76.344438][ T21] ? __ext4_mark_inode_dirty+0x910/0x910 [ 76.350065][ T21] ? check_preemption_disabled+0x50/0x130 [ 76.355777][ T21] ? __brelse+0x84/0xa0 [ 76.359932][ T21] ? mark_lock+0x82/0x1660 [ 76.364379][ T21] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 76.370353][ T21] ? ext4_da_get_block_prep+0x1120/0x1120 [ 76.376066][ T21] ? __ext4_mark_inode_dirty+0x910/0x910 [ 76.381688][ T21] do_writepages+0xec/0x290 [ 76.386195][ T21] ? writeback_set_ratelimit+0x150/0x150 [ 76.391824][ T21] ? lock_downgrade+0x830/0x830 [ 76.396669][ T21] ? writeback_sb_inodes+0x3a6/0xf40 [ 76.401948][ T21] ? lock_is_held_type+0xbb/0xf0 [ 76.406883][ T21] __writeback_single_inode+0x125/0x1400 [ 76.412510][ T21] ? _raw_spin_unlock+0x24/0x40 [ 76.417358][ T21] ? wbc_attach_and_unlock_inode+0x11d/0x9d0 [ 76.423340][ T21] writeback_sb_inodes+0x53d/0xf40 [ 76.428452][ T21] ? __writeback_single_inode+0x1400/0x1400 [ 76.434350][ T21] __writeback_inodes_wb+0xc6/0x280 [ 76.439546][ T21] wb_writeback+0x8bb/0xd40 [ 76.444051][ T21] ? __writeback_inodes_wb+0x280/0x280 [ 76.449505][ T21] ? _find_next_bit.constprop.0+0x1a3/0x200 [ 76.455399][ T21] ? cpumask_next+0x3c/0x40 [ 76.459906][ T21] ? get_nr_dirty_inodes+0x1b2/0x250 [ 76.465188][ T21] wb_workfn+0x8f5/0x13e0 [ 76.469514][ T21] ? inode_wait_for_writeback+0x30/0x30 [ 76.475059][ T21] ? lock_acquire+0x1f3/0xaf0 [ 76.479735][ T21] ? process_one_work+0x85f/0x1670 [ 76.484840][ T21] ? lock_release+0x8f0/0x8f0 [ 76.489521][ T21] ? _raw_spin_unlock_irq+0x1f/0x80 [ 76.494712][ T21] ? lock_is_held_type+0xbb/0xf0 [ 76.499650][ T21] process_one_work+0x94c/0x1670 [ 76.505172][ T21] ? lock_release+0x8f0/0x8f0 [ 76.510715][ T21] ? pwq_dec_nr_in_flight+0x320/0x320 [ 76.516084][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 76.521016][ T21] ? lockdep_hardirqs_off+0x96/0xd0 executing program executing program executing program executing program executing program executing program [ 76.526215][ T21] worker_thread+0x64c/0x1120 [ 76.530900][ T21] ? __kthread_parkme+0x13f/0x1e0 [ 76.535921][ T21] ? process_one_work+0x1670/0x1670 [ 76.541110][ T21] kthread+0x3b5/0x4a0 [ 76.545173][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 76.550281][ T21] ret_from_fork+0x1f/0x30 [ 76.554689][ T21] Modules linked in: executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 77.060260][ T21] ---[ end trace f17ebfb08907d3c4 ]--- [ 77.088897][ T21] RIP: 0010:__ext4_journal_get_write_access+0x6b/0x2b0 executing program executing program executing program executing program executing program executing program [ 77.131486][ T21] Code: 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 25 02 00 00 48 b8 00 00 00 00 00 fc ff df 48 8b 5d 30 48 8d 7b 10 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 f8 01 00 00 4c 8b 73 10 4d 85 f6 0f 84 f4 00 00 executing program executing program executing program executing program executing program executing program executing program executing program [ 77.262041][ T21] RSP: 0018:ffffc90000dd6db8 EFLAGS: 00010202 [ 77.284469][ T21] RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffff8880a4b83740 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 77.309896][ T21] RDX: 0000000000000002 RSI: ffffffff8a067e40 RDI: 0000000000000010 [ 77.347400][ T21] RBP: ffff8880a4b83740 R08: 0000000000000001 R09: ffff8880a900ee60 executing program executing program executing program executing program executing program [ 77.380350][ T21] R10: fffffbfff16b2399 R11: 0000000000000000 R12: 0000000000000001 executing program executing program [ 77.456446][ T21] R13: 1ffff920001badcb R14: ffff888214b28000 R15: 0000000000000c9d executing program executing program executing program executing program executing program executing program executing program [ 77.496803][ T21] FS: 0000000000000000(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 executing program executing program executing program executing program executing program executing program [ 77.550457][ T21] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 executing program executing program executing program executing program executing program executing program [ 77.599560][ T21] CR2: 00007fb7f0a26e78 CR3: 0000000009e8d000 CR4: 00000000001506e0 executing program executing program executing program executing program executing program executing program [ 77.646743][ T21] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 77.675666][ T21] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 executing program [ 77.717032][ T21] Kernel panic - not syncing: Fatal exception [ 77.724142][ T21] Kernel Offset: disabled [ 77.728452][ T21] Rebooting in 86400 seconds..