[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 28.718925] kauditd_printk_skb: 7 callbacks suppressed [ 28.718936] audit: type=1800 audit(1545482395.540:29): pid=5899 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 28.746675] audit: type=1800 audit(1545482395.540:30): pid=5899 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 [....] startpar: service(s) returned failure: ssh ...[?25l[?1c7[FAIL8[?25h[?0c failed! Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.85' (ECDSA) to the list of known hosts. 2018/12/22 12:40:03 fuzzer started 2018/12/22 12:40:05 connecting to host at 10.128.0.26:46807 2018/12/22 12:40:05 checking revisions... 2018/12/22 12:40:05 testing simple program... syzkaller login: [ 39.041697] ld (6085) used greatest stack depth: 15512 bytes left [ 39.204872] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program [ 60.082306] WARNING: CPU: 1 PID: 45 at include/linux/blk-cgroup.h:518 __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.092648] Kernel panic - not syncing: panic_on_warn set ... [ 60.098543] CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 4.20.0-rc7-next-20181221 #185 [ 60.106684] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.116045] Workqueue: writeback wb_workfn (flush-8:0) [ 60.121319] Call Trace: [ 60.123912] dump_stack+0x1d3/0x2c6 [ 60.127546] ? dump_stack_print_info.cold.1+0x20/0x20 [ 60.132751] panic+0x2ad/0x632 [ 60.135947] ? add_taint.cold.5+0x16/0x16 [ 60.140105] ? __warn.cold.8+0x5/0x4f [ 60.143919] ? __warn+0xe8/0x1d0 [ 60.147323] ? __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.152700] __warn.cold.8+0x20/0x4f [ 60.156416] ? rcu_softirq_qs+0x20/0x20 [ 60.160399] ? __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.165770] report_bug+0x254/0x2d0 [ 60.169405] do_error_trap+0x11b/0x200 [ 60.173300] do_invalid_op+0x36/0x40 [ 60.177019] ? __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.182386] invalid_op+0x14/0x20 [ 60.185841] RIP: 0010:__bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.191815] Code: 7b 50 48 89 f8 48 c1 e8 03 42 80 3c 20 00 0f 85 f1 00 00 00 48 8b 43 50 4c 89 ef e8 bf c6 88 04 e9 a4 f9 ff ff e8 c5 ad 07 fe <0f> 0b e9 5c fa ff ff e8 b9 ad 07 fe e8 ab e2 88 fd e9 fe f9 ff ff [ 60.210712] RSP: 0018:ffff8881d95d5738 EFLAGS: 00010293 [ 60.216069] RAX: ffff8881d95ca440 RBX: 0000000000000000 RCX: ffffffff83779576 [ 60.223338] RDX: 0000000000000000 RSI: ffffffff83779b1b RDI: 0000000000000005 [ 60.230606] RBP: ffff8881d95d58b8 R08: ffff8881d95ca440 R09: ffffed103b5e5b77 [ 60.237889] R10: ffffed103b5e5b77 R11: ffff8881daf2dbbb R12: ffff8881cee88200 [ 60.245200] R13: ffff8881b56609c0 R14: ffff8881bd7367d8 R15: ffff8881cee88200 [ 60.252485] ? __bio_associate_blkg.isra.36+0x266/0x8f0 [ 60.257846] ? __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.263223] ? __bio_associate_blkg.isra.36+0x80b/0x8f0 [ 60.268587] ? kasan_check_write+0x14/0x20 [ 60.272850] ? bio_init+0x139/0x260 [ 60.276481] ? bio_reset+0x510/0x510 [ 60.280199] ? mark_held_locks+0x130/0x130 [ 60.284446] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.289984] ? bio_alloc_bioset+0x2cc/0x6f0 [ 60.294302] ? mark_held_locks+0x130/0x130 [ 60.298540] ? bvec_alloc+0x2d0/0x2d0 [ 60.302343] __bio_clone_fast+0x412/0x5e0 [ 60.306498] bio_clone_fast+0x42/0x110 [ 60.310414] bio_split+0x86/0x260 [ 60.313871] blk_queue_split+0xa1e/0x2080 [ 60.318021] ? blk_queue_bounce+0x126/0x29b6 [ 60.322448] ? __blk_recalc_rq_segments+0xe20/0xe20 [ 60.327464] ? find_held_lock+0x36/0x1c0 [ 60.331529] ? graph_lock+0x270/0x270 [ 60.335396] ? ktime_get+0x332/0x400 [ 60.339123] ? find_held_lock+0x36/0x1c0 [ 60.343206] blk_mq_make_request+0x2e7/0x1e30 [ 60.347713] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.353257] ? check_preemption_disabled+0x48/0x280 [ 60.358278] ? blk_mq_try_issue_directly+0xaf0/0xaf0 [ 60.363414] ? __lock_is_held+0xb5/0x140 [ 60.367506] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 60.373058] ? trace_event_raw_event_block_rq_requeue+0x6f0/0x6f0 [ 60.379827] ? __set_page_dirty_buffers+0x810/0x810 [ 60.384870] ? ___might_sleep+0x1ed/0x300 [ 60.389020] ? ext4_mark_iloc_dirty+0x17a9/0x2f30 [ 60.393861] ? arch_local_save_flags+0x40/0x40 [ 60.398444] ? lock_downgrade+0x900/0x900 [ 60.402606] ? kasan_check_write+0x14/0x20 [ 60.406845] ? __brelse+0x104/0x180 [ 60.410479] ? block_commit_write+0x30/0x30 [ 60.414807] ? __ext4_handle_dirty_metadata+0x1e0/0x5a0 [ 60.420181] ? kasan_check_write+0x14/0x20 [ 60.424420] ? ext4_mark_iloc_dirty+0x199a/0x2f30 [ 60.429324] generic_make_request+0x9a5/0x1890 [ 60.433936] ? ___might_sleep+0x1ed/0x300 [ 60.438090] ? blk_queue_enter+0x11f0/0x11f0 [ 60.442500] ? other_inode_match+0xbb0/0xbb0 [ 60.446932] ? __might_sleep+0x95/0x190 [ 60.450928] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 60.456468] ? __ext4_journal_get_write_access+0x6d/0xa0 [ 60.461925] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.467465] ? ext4_reserve_inode_write+0x148/0x260 [ 60.472502] ? ext4_mark_inode_dirty+0x266/0xb20 [ 60.477268] ? ext4_expand_extra_isize+0x5b0/0x5b0 [ 60.482213] ? lock_release+0xa00/0xa00 [ 60.486196] submit_bio+0xba/0x460 [ 60.489740] ? submit_bio+0xba/0x460 [ 60.493461] ? generic_make_request+0x1890/0x1890 [ 60.498313] ? up_write+0x7b/0x220 [ 60.501859] ? down_write_nested+0x130/0x130 [ 60.506277] ? down_read+0x120/0x120 [ 60.509998] ext4_io_submit+0x197/0x230 [ 60.513977] ext4_writepages+0x1c4b/0x4190 [ 60.518247] ? ext4_mark_inode_dirty+0xb20/0xb20 [ 60.523005] ? graph_lock+0x240/0x270 [ 60.526810] ? print_usage_bug+0xc0/0xc0 [ 60.530927] ? __lock_acquire+0x62f/0x4c20 [ 60.535174] ? hctx_unlock+0xde/0x150 [ 60.538993] ? print_usage_bug+0xc0/0xc0 [ 60.543067] ? __lock_acquire+0x62f/0x4c20 [ 60.547306] ? mark_held_locks+0x130/0x130 [ 60.551541] ? __ext4_get_inode_loc+0x470/0x1330 [ 60.556309] ? mark_held_locks+0x130/0x130 [ 60.560551] ? graph_lock+0x270/0x270 [ 60.564355] ? kasan_check_write+0x14/0x20 [ 60.568590] ? __brelse+0x104/0x180 [ 60.572227] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.577789] ? check_preemption_disabled+0x48/0x280 [ 60.582830] ? ext4_mark_inode_dirty+0xb20/0xb20 [ 60.587596] do_writepages+0x9a/0x1a0 [ 60.591398] ? ext4_mark_inode_dirty+0xb20/0xb20 [ 60.596176] ? do_writepages+0x9a/0x1a0 [ 60.600174] __writeback_single_inode+0x20a/0x1660 [ 60.605116] ? __mark_inode_dirty+0x1510/0x1510 [ 60.609794] ? find_held_lock+0x36/0x1c0 [ 60.613868] ? find_held_lock+0x36/0x1c0 [ 60.617956] ? wbc_attach_and_unlock_inode+0x5c0/0xa30 [ 60.623233] ? lock_downgrade+0x900/0x900 [ 60.627390] ? find_held_lock+0x13f/0x1c0 [ 60.631541] ? kasan_check_read+0x11/0x20 [ 60.635701] ? do_raw_spin_unlock+0xa7/0x330 [ 60.640131] ? do_raw_spin_trylock+0x270/0x270 [ 60.644721] ? __lock_is_held+0xb5/0x140 [ 60.648798] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 60.654338] ? wbc_attach_and_unlock_inode+0x675/0xa30 [ 60.659622] ? __writeback_single_inode+0x1660/0x1660 [ 60.664846] writeback_sb_inodes+0x71f/0x1210 [ 60.669359] ? wbc_detach_inode+0x960/0x960 [ 60.673694] ? lock_release+0xa00/0xa00 [ 60.677702] ? down_read_trylock+0xda/0x140 [ 60.682029] ? trylock_super+0x22/0x110 [ 60.686022] ? downgrade_write+0x270/0x270 [ 60.690271] ? queue_io+0x3dd/0x800 [ 60.693908] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 60.699454] __writeback_inodes_wb+0x1b9/0x340 [ 60.704048] ? writeback_sb_inodes+0x1210/0x1210 [ 60.708825] ? __lock_is_held+0xb5/0x140 [ 60.712915] wb_writeback+0xa73/0xfc0 [ 60.716734] ? writeback_inodes_wb.constprop.50+0x330/0x330 [ 60.722453] ? widen_string+0xe0/0x2e0 [ 60.726353] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 60.731544] ? print_usage_bug+0xc0/0xc0 [ 60.735612] ? string+0x225/0x2d0 [ 60.739075] ? widen_string+0x2e0/0x2e0 [ 60.743062] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 60.748083] ? find_next_bit+0x104/0x130 [ 60.752162] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 60.757204] ? find_next_bit+0x104/0x130 [ 60.761279] ? cpumask_next+0x41/0x50 [ 60.765081] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 60.770104] ? get_nr_dirty_inodes+0xd6/0x130 [ 60.774603] ? __local_bh_enable_ip+0x160/0x260 [ 60.779280] ? get_nr_dirty_pages+0x17c/0x1f0 [ 60.783804] ? _raw_spin_unlock_bh+0x30/0x40 [ 60.788221] ? inode_sleep_on_writeback+0x240/0x240 [ 60.793244] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.798795] ? check_preemption_disabled+0x48/0x280 [ 60.803814] ? wb_workfn+0x521/0x1790 [ 60.807619] ? wb_workfn+0x521/0x1790 [ 60.811430] ? __local_bh_enable_ip+0x160/0x260 [ 60.816107] wb_workfn+0x1008/0x1790 [ 60.819826] ? __lock_acquire+0x62f/0x4c20 [ 60.824079] ? inode_wait_for_writeback+0x40/0x40 [ 60.828932] ? mark_held_locks+0x130/0x130 [ 60.833172] ? graph_lock+0x270/0x270 [ 60.837024] ? graph_lock+0x270/0x270 [ 60.840825] ? lock_is_held_type+0x210/0x210 [ 60.845247] ? graph_lock+0x270/0x270 [ 60.849060] ? debug_object_deactivate+0x37d/0x480 [ 60.853992] ? lock_downgrade+0x900/0x900 [ 60.858163] ? find_held_lock+0x36/0x1c0 [ 60.862231] ? graph_lock+0x270/0x270 [ 60.866041] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 60.871582] ? check_preemption_disabled+0x48/0x280 [ 60.876633] ? __lock_is_held+0xb5/0x140 [ 60.880729] process_one_work+0xc90/0x1c40 [ 60.884994] ? mark_held_locks+0x130/0x130 [ 60.889260] ? pwq_dec_nr_in_flight+0x4a0/0x4a0 [ 60.893934] ? __bpf_trace_sched_wake_idle_without_ipi+0x10/0x10 [ 60.900078] ? __switch_to_asm+0x34/0x70 [ 60.904198] ? __switch_to_asm+0x34/0x70 [ 60.908272] ? __switch_to_asm+0x40/0x70 [ 60.912336] ? __switch_to_asm+0x34/0x70 [ 60.916394] ? __switch_to_asm+0x40/0x70 [ 60.920485] ? __switch_to_asm+0x34/0x70 [ 60.924546] ? __switch_to_asm+0x34/0x70 [ 60.928611] ? __switch_to_asm+0x34/0x70 [ 60.932690] ? __switch_to_asm+0x40/0x70 [ 60.936752] ? __switch_to_asm+0x34/0x70 [ 60.940816] ? __switch_to_asm+0x40/0x70 [ 60.944877] ? __switch_to_asm+0x34/0x70 [ 60.948980] ? __sched_text_start+0x8/0x8 [ 60.953129] ? graph_lock+0x270/0x270 [ 60.956945] ? lock_downgrade+0x900/0x900 [ 60.961103] ? kasan_check_read+0x11/0x20 [ 60.965254] ? do_raw_spin_unlock+0xa7/0x330 [ 60.969673] ? find_held_lock+0x36/0x1c0 [ 60.973742] ? lock_acquire+0x1ed/0x520 [ 60.977718] ? worker_thread+0x3e0/0x1390 [ 60.981877] ? kasan_check_write+0x14/0x20 [ 60.986115] ? do_raw_spin_lock+0x14f/0x350 [ 60.990445] ? __schedule+0x1ed0/0x1ed0 [ 60.994425] ? rwlock_bug.part.2+0x90/0x90 [ 60.998665] ? trace_hardirqs_on+0x310/0x310 [ 61.003105] worker_thread+0x17f/0x1390 [ 61.007081] ? __bpf_trace_sched_wake_idle_without_ipi+0x10/0x10 [ 61.013243] ? process_one_work+0x1c40/0x1c40 [ 61.017748] ? __schedule+0x9e6/0x1ed0 [ 61.021635] ? kmem_cache_alloc_trace+0x154/0x750 [ 61.026493] ? __sched_text_start+0x8/0x8 [ 61.030674] ? __kthread_parkme+0xce/0x1a0 [ 61.034928] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 61.040035] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 61.045141] ? lockdep_hardirqs_on+0x421/0x5c0 [ 61.049736] ? trace_hardirqs_on+0xbd/0x310 [ 61.054058] ? kasan_check_read+0x11/0x20 [ 61.058213] ? __kthread_parkme+0xce/0x1a0 [ 61.062451] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 61.067908] ? __schedule+0x1ed0/0x1ed0 [ 61.071895] ? _raw_spin_unlock_irqrestore+0x6d/0xd0 [ 61.077021] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 61.082578] ? __kthread_parkme+0xfb/0x1a0 [ 61.086834] ? process_one_work+0x1c40/0x1c40 [ 61.091330] kthread+0x35a/0x440 [ 61.094699] ? kthread_bind+0x40/0x40 [ 61.098524] ret_from_fork+0x3a/0x50 [ 61.103415] Kernel Offset: disabled [ 61.107099] Rebooting in 86400 seconds..