[ 8.771377] random: sshd: uninitialized urandom read (32 bytes read) [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 15.136876] random: sshd: uninitialized urandom read (32 bytes read) [ 15.286602] audit: type=1400 audit(1566023694.977:6): avc: denied { map } for pid=1741 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 [ 15.331780] random: sshd: uninitialized urandom read (32 bytes read) [ 15.775681] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.84' (ECDSA) to the list of known hosts. [ 21.431825] urandom_read: 1 callbacks suppressed [ 21.431828] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 21.536682] audit: type=1400 audit(1566023701.227:7): avc: denied { map } for pid=1759 comm="syz-executor758" path="/root/syz-executor758101835" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 21.543711] kasan: CONFIG_KASAN_INLINE enabled [ 21.567571] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 21.575597] general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 21.582461] Modules linked in: [ 21.585676] CPU: 0 PID: 1759 Comm: syz-executor758 Not tainted 4.14.139+ #34 [ 21.592843] task: (ptrval) task.stack: (ptrval) [ 21.598882] RIP: 0010:__blockdev_direct_IO+0x1dcf/0xe24e [ 21.604429] RSP: 0018:ffff8881d100f330 EFLAGS: 00010202 [ 21.609765] RAX: dffffc0000000000 RBX: ffffea00073f341c RCX: ffffffffa2c36753 [ 21.617008] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000020 [ 21.624246] RBP: ffff8881d100f668 R08: 0000000000000000 R09: fffff94000e7e684 [ 21.631483] R10: fffff94000e7e683 R11: ffffea00073f341f R12: ffffea00073f3400 [ 21.638726] R13: ffffea00073f3400 R14: 0000000000000000 R15: ffff8881d1b08000 [ 21.645974] FS: 00000000019a0880(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 [ 21.654175] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 21.660034] CR2: 0000000020011000 CR3: 00000001d188c005 CR4: 00000000001606b0 [ 21.667276] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 21.674513] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 21.681757] Call Trace: [ 21.684327] ? sb_init_dio_done_wq+0x90/0x90 [ 21.688723] ? __bfs+0x25/0x540 [ 21.691990] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 21.697589] ? lock_downgrade+0x5d0/0x5d0 [ 21.701709] ext4_direct_IO+0xa4f/0x2820 [ 21.705756] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 21.711354] ? ext4_da_write_begin+0x10c0/0x10c0 [ 21.716082] ? current_time+0x16/0xb0 [ 21.719850] ? mark_held_locks+0xa6/0xf0 [ 21.724000] ? timespec_trunc+0xc9/0x140 [ 21.728034] ? put_itimerspec64+0x1c0/0x1c0 [ 21.732325] ? trace_hardirqs_on_caller+0x37b/0x540 [ 21.737404] ? current_kernel_time64+0xb6/0x100 [ 21.742051] ? current_time+0x89/0xb0 [ 21.745828] ? filemap_check_errors+0x8b/0xb0 [ 21.750298] generic_file_direct_write+0x1e4/0x430 [ 21.755200] __generic_file_write_iter+0x209/0x550 [ 21.760107] ? generic_write_checks+0x252/0x410 [ 21.764746] ext4_file_write_iter+0x58f/0xdb0 [ 21.769209] ? ext4_llseek+0x7f0/0x7f0 [ 21.773069] do_iter_readv_writev+0x379/0x580 [ 21.777540] ? clone_verify_area+0x1e0/0x1e0 [ 21.781920] ? avc_policy_seqno+0x5/0x10 [ 21.786149] ? security_file_permission+0x88/0x1e0 [ 21.791051] do_iter_write+0x152/0x550 [ 21.794912] vfs_iter_write+0x70/0xa0 [ 21.798688] iter_file_splice_write+0x560/0xa50 [ 21.803328] ? vmsplice_to_user+0x1e0/0x1e0 [ 21.807772] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 21.813209] ? rcu_read_lock_sched_held+0x10a/0x130 [ 21.818319] ? vmsplice_to_user+0x1e0/0x1e0 [ 21.822611] SyS_splice+0xcd6/0x1270 [ 21.826296] ? selinux_file_fcntl+0x86/0x140 [ 21.830681] ? compat_SyS_vmsplice+0x150/0x150 [ 21.835241] ? do_syscall_64+0x43/0x520 [ 21.839183] ? compat_SyS_vmsplice+0x150/0x150 [ 21.843738] do_syscall_64+0x19b/0x520 [ 21.847601] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 21.852907] RIP: 0033:0x440319 [ 21.856084] RSP: 002b:00007ffc49acada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 21.863770] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440319 [ 21.871018] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 21.878566] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 21.885816] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401ba0 [ 21.893265] R13: 0000000000401c30 R14: 0000000000000000 R15: 0000000000000000 [ 21.900514] Code: 4c a4 e8 e5 7f e9 ff 0f 0b e8 3e d4 cd ff 48 8b 84 24 e8 00 00 00 48 8d 78 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 a0 00 00 48 8b 84 24 e8 00 00 00 4c 8b 60 [ 21.919801] RIP: __blockdev_direct_IO+0x1dcf/0xe24e RSP: ffff8881d100f330 [ 21.927213] ---[ end trace c4bdc841745cfb7f ]--- [ 21.932218] Kernel panic - not syncing: Fatal exception [ 21.938206] Kernel Offset: 0x21600000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 21.949142] Rebooting in 86400 seconds..