[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 31.281422] random: sshd: uninitialized urandom read (32 bytes read) [ 31.544590] kauditd_printk_skb: 10 callbacks suppressed [ 31.544598] audit: type=1400 audit(1555659434.183:35): avc: denied { map } for pid=6949 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 31.594612] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 32.118357] random: sshd: uninitialized urandom read (32 bytes read) [ 423.726113] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.46' (ECDSA) to the list of known hosts. [ 429.279514] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program [ 429.416571] audit: type=1400 audit(1555659832.053:36): avc: denied { map } for pid=6963 comm="syz-executor108" path="/root/syz-executor108223018" dev="sda1" ino=1426 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program [ 714.720214] INFO: task syz-executor108:6975 blocked for more than 140 seconds. [ 714.727899] Not tainted 4.14.112 #2 [ 714.732534] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 714.740544] syz-executor108 D28528 6975 6963 0x00000004 [ 714.746261] Call Trace: [ 714.748898] __schedule+0x7be/0x1cf0 [ 714.756117] ? pci_mmcfg_check_reserved+0x150/0x150 [ 714.761218] ? _raw_spin_unlock_irq+0x28/0x90 [ 714.765713] schedule+0x92/0x1c0 [ 714.769072] rwsem_down_read_failed+0x1f4/0x380 [ 714.774100] ? __rwsem_down_read_failed_common.part.0+0x80/0x80 [ 714.781014] ? debug_object_free+0x1fc/0x3f0 [ 714.785489] call_rwsem_down_read_failed+0x18/0x30 [ 714.790919] down_read+0x49/0xb0 [ 714.794301] ? __do_page_fault+0x894/0xb80 [ 714.798536] __do_page_fault+0x894/0xb80 [ 714.802904] ? SyS_nanosleep+0x12b/0x170 [ 714.806974] ? vmalloc_fault+0xe60/0xe60 [ 714.811313] ? page_fault+0x2f/0x50 [ 714.814944] do_page_fault+0x71/0x515 [ 714.818747] ? page_fault+0x2f/0x50 [ 714.822670] page_fault+0x45/0x50 [ 714.826124] RIP: 0033:0x4ab79d [ 714.829304] RSP: 002b:00007ffd56766b50 EFLAGS: 00010206 [ 714.835005] RAX: 00000000004ab8c0 RBX: 0000000000000001 RCX: 00000000006e0330 [ 714.842302] RDX: 0000000000407620 RSI: 0000000000000000 RDI: 00000000004ccb90 [ 714.849835] RBP: 00007ffd56766b70 R08: 000000037ffffa00 R09: 000000037ffffa00 [ 714.857601] R10: 00007ffd56766be0 R11: 0000000000000000 R12: 0000000000000001 [ 714.864906] R13: 00000000006e0320 R14: 000000000000002d R15: 20c49ba5e353f7cf [ 714.872480] INFO: task syz-executor108:6976 blocked for more than 140 seconds. [ 714.879858] Not tainted 4.14.112 #2 [ 714.884326] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 714.892326] syz-executor108 D29376 6976 6963 0x80000004 [ 714.897972] Call Trace: [ 714.900877] __schedule+0x7be/0x1cf0 [ 714.904683] ? pci_mmcfg_check_reserved+0x150/0x150 [ 714.911365] ? _raw_spin_unlock_irq+0x28/0x90 [ 714.915877] schedule+0x92/0x1c0 [ 714.919239] rwsem_down_read_failed+0x1f4/0x380 [ 714.924214] ? __rwsem_down_read_failed_common.part.0+0x80/0x80 [ 714.930323] call_rwsem_down_read_failed+0x18/0x30 [ 714.935253] down_read+0x49/0xb0 [ 714.938611] ? do_exit+0x3d2/0x2c10 [ 714.942694] do_exit+0x3d2/0x2c10 [ 714.946157] ? find_held_lock+0x35/0x130 [ 714.950481] ? mm_update_next_owner+0x5d0/0x5d0 [ 714.955173] do_group_exit+0x111/0x330 [ 714.959070] get_signal+0x348/0x1a80 [ 714.963096] ? __mutex_unlock_slowpath+0x71/0x800 [ 714.967959] ? wait_for_completion+0x420/0x420 [ 714.973274] do_signal+0x86/0x1980 [ 714.976821] ? perf_ioctl+0x202/0xcb0 [ 714.981008] ? SYSC_perf_event_open+0x24c0/0x24c0 [ 714.985853] ? setup_sigcontext+0x7d0/0x7d0 [ 714.990441] ? SYSC_perf_event_open+0x24c0/0x24c0 [ 714.995280] ? do_vfs_ioctl+0xef/0x1070 [ 714.999250] ? selinux_file_mprotect+0x5d0/0x5d0 [ 715.004261] ? lock_downgrade+0x6e0/0x6e0 [ 715.008412] ? ioctl_preallocate+0x1c0/0x1c0 [ 715.013084] ? SyS_futex+0x215/0x302 [ 715.016797] ? SyS_futex+0x222/0x302 [ 715.020750] ? exit_to_usermode_loop+0x3d/0x220 [ 715.025424] exit_to_usermode_loop+0x15c/0x220 [ 715.030007] do_syscall_64+0x4a9/0x630 [ 715.034146] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 715.038991] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 715.045122] RIP: 0033:0x4468f9 [ 715.048326] RSP: 002b:00007f00a69a4db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 715.056316] RAX: fffffffffffffe00 RBX: 00000000006dbc28 RCX: 00000000004468f9 [ 715.063612] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28 [ 715.071153] RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 [ 715.078419] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c [ 715.085943] R13: 00007ffd56766b4f R14: 00007f00a69a59c0 R15: 20c49ba5e353f7cf [ 715.093348] [ 715.093348] Showing all locks held in the system: [ 715.099669] 1 lock held by khungtaskd/1007: [ 715.104111] #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7f/0x21f [ 715.113218] 2 locks held by getty/6939: [ 715.117187] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.125915] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.135244] 2 locks held by getty/6940: [ 715.139208] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.147913] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.157237] 2 locks held by getty/6941: [ 715.161219] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.169894] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.179278] 2 locks held by getty/6942: [ 715.183273] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.191995] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.201333] 2 locks held by getty/6943: [ 715.205301] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.214034] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.223383] 2 locks held by getty/6944: [ 715.227349] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.236099] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.245433] 2 locks held by getty/6945: [ 715.249395] #0: (&tty->ldisc_sem){++++}, at: [] ldsem_down_read+0x33/0x40 [ 715.258150] #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1e6/0x17b0 [ 715.267480] 1 lock held by syz-executor108/6975: [ 715.272282] #0: (&mm->mmap_sem){++++}, at: [] __do_page_fault+0x894/0xb80 [ 715.280991] 1 lock held by syz-executor108/6976: [ 715.285735] #0: (&mm->mmap_sem){++++}, at: [] do_exit+0x3d2/0x2c10 [ 715.293876] [ 715.295494] ============================================= [ 715.295494] [ 715.303582] NMI backtrace for cpu 0 [ 715.307217] CPU: 0 PID: 1007 Comm: khungtaskd Not tainted 4.14.112 #2 [ 715.313784] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 715.323124] Call Trace: [ 715.325708] dump_stack+0x138/0x19c [ 715.329332] nmi_cpu_backtrace.cold+0x57/0x94 [ 715.333825] ? irq_force_complete_move.cold+0x7d/0x7d [ 715.339007] nmi_trigger_cpumask_backtrace+0x141/0x189 [ 715.344280] arch_trigger_cpumask_backtrace+0x14/0x20 [ 715.349462] watchdog+0x5d8/0xb80 [ 715.352913] kthread+0x31c/0x430 [ 715.356276] ? reset_hung_task_detector+0x20/0x20 [ 715.361109] ? kthread_create_on_node+0xd0/0xd0 [ 715.365769] ret_from_fork+0x3a/0x50 [ 715.369560] Sending NMI from CPU 0 to CPUs 1: [ 715.374368] NMI backtrace for cpu 1 [ 715.374371] CPU: 1 PID: 6977 Comm: syz-executor108 Not tainted 4.14.112 #2 [ 715.374375] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 715.374377] task: ffff888085a4c300 task.stack: ffff8880a4080000 [ 715.374379] RIP: 0010:lock_release+0x5f5/0x940 [ 715.374381] RSP: 0018:ffff8880a4087a90 EFLAGS: 00000086 [ 715.374386] RAX: 0000000000000000 RBX: 1ffff11014810f58 RCX: 1ffffffff0f56320 [ 715.374388] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff888085a4cb7c [ 715.374391] RBP: ffff8880a4087b28 R08: dffffc0000000000 R09: ffffffff88c882f8 [ 715.374394] R10: 0000000000000000 R11: ffff888085a4c300 R12: ffff88808a42c5c0 [ 715.374396] R13: ffffffff816d08de R14: ffff888085a4c300 R15: ffff8880a4087b00 [ 715.374399] FS: 00007f00a6984700(0000) GS:ffff8880aef00000(0000) knlGS:0000000000000000 [ 715.374401] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 715.374404] CR2: 00007f00a6983e78 CR3: 00000000897d7000 CR4: 00000000001406e0 [ 715.374407] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 715.374410] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 715.374411] Call Trace: [ 715.374413] ? retint_kernel+0x2d/0x2d [ 715.374420] ? perf_mmap+0x50d/0x13f0 [ 715.374422] ? lock_downgrade+0x6e0/0x6e0 [ 715.374424] ? mutex_trylock+0x1c0/0x1c0 [ 715.374426] __mutex_unlock_slowpath+0x71/0x800 [ 715.374428] ? wait_for_completion+0x420/0x420 [ 715.374430] mutex_unlock+0xd/0x10 [ 715.374431] perf_mmap+0x64e/0x13f0 [ 715.374433] mmap_region+0x858/0x1030 [ 715.374435] do_mmap+0x5b8/0xcd0 [ 715.374437] vm_mmap_pgoff+0x17a/0x1d0 [ 715.374439] ? vma_is_stack_for_current+0xa0/0xa0 [ 715.374441] ? __fget+0x237/0x370 [ 715.374443] SyS_mmap_pgoff+0x3ca/0x520 [ 715.374445] ? find_mergeable_anon_vma+0x2c0/0x2c0 [ 715.374447] ? do_syscall_64+0x53/0x630 [ 715.374448] ? align_vdso_addr+0x60/0x60 [ 715.374450] SyS_mmap+0x16/0x20 [ 715.374452] do_syscall_64+0x1eb/0x630 [ 715.374454] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 715.374456] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 715.374458] RIP: 0033:0x4468f9 [ 715.374460] RSP: 002b:00007f00a6983da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 [ 715.374465] RAX: ffffffffffffffda RBX: 00000000006dbc38 RCX: 00000000004468f9 [ 715.374467] RDX: 0000000000000000 RSI: 0000000000003000 RDI: 0000000020ffd000 [ 715.374470] RBP: 00000000006dbc30 R08: 0000000000000003 R09: 0000000000000000 [ 715.374473] R10: 0000000000001011 R11: 0000000000000246 R12: 00000000006dbc3c [ 715.374475] R13: 00007ffd56766b4f R14: 00007f00a69849c0 R15: 20c49ba5e353f7cf [ 715.374477] Code: 65 ff 05 ef b7 b9 7e 48 8b 05 80 39 d9 06 e8 63 e4 04 00 85 c0 74 0d 80 3d cc e4 d8 06 00 0f 84 07 01 00 00 65 ff 0d cb b7 b9 7e <0f> 85 71 fb ff ff e8 74 0c b8 ff e9 67 fb ff ff 0f 0b 0f 0b 0f [ 715.375091] Kernel panic - not syncing: hung_task: blocked tasks [ 715.645378] CPU: 0 PID: 1007 Comm: khungtaskd Not tainted 4.14.112 #2 [ 715.651946] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 715.661375] Call Trace: [ 715.663962] dump_stack+0x138/0x19c [ 715.667587] panic+0x1f2/0x438 [ 715.670771] ? add_taint.cold+0x16/0x16 [ 715.674739] ? irq_force_complete_move.cold+0x7d/0x7d [ 715.680018] watchdog+0x5e9/0xb80 [ 715.683467] kthread+0x31c/0x430 [ 715.686828] ? reset_hung_task_detector+0x20/0x20 [ 715.691658] ? kthread_create_on_node+0xd0/0xd0 [ 715.696333] ret_from_fork+0x3a/0x50 [ 715.701335] Kernel Offset: disabled [ 715.705017] Rebooting in 86400 seconds..