[ 29.783935] 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. [ 30.860014] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 31.141342] random: sshd: uninitialized urandom read (32 bytes read) [ 31.674366] random: sshd: uninitialized urandom read (32 bytes read) [ 41.044643] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.1.0' (ECDSA) to the list of known hosts. [ 46.625952] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 46.752664] kauditd_printk_skb: 10 callbacks suppressed [ 46.752673] audit: type=1400 audit(1571586237.504:36): avc: denied { map } for pid=6907 comm="syz-executor479" path="/root/syz-executor479783216" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 46.757681] kasan: CONFIG_KASAN_INLINE enabled [ 46.758246] audit: type=1800 audit(1571586237.504:37): pid=6907 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="collect_data" cause="failed(directio)" comm="syz-executor479" name="bus" dev="sda1" ino=16484 res=0 [ 46.785478] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 46.820671] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 46.826888] Modules linked in: [ 46.830165] CPU: 0 PID: 6907 Comm: syz-executor479 Not tainted 4.14.150 #0 [ 46.837161] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.846502] task: ffff888079d9a140 task.stack: ffff8880a8fc0000 [ 46.852707] RIP: 0010:do_blockdev_direct_IO+0x1c75/0x7fd0 [ 46.858354] RSP: 0018:ffff8880a8fc74c0 EFLAGS: 00010202 [ 46.863791] RAX: dffffc0000000000 RBX: ffffea000230e21c RCX: 000000000000000c [ 46.871068] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000020 [ 46.878321] RBP: ffff8880a8fc77d8 R08: ffffed1012a64029 R09: ffff8880953200c0 [ 46.885693] R10: ffffed1012a64028 R11: ffff888095320147 R12: ffffea000230e200 [ 46.893145] R13: ffffea000230e200 R14: 0000000000000000 R15: ffff88809eb11a40 [ 46.900511] FS: 00000000019ca880(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000 [ 46.908809] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 46.914742] CR2: 000055d88df0d190 CR3: 0000000078d63000 CR4: 00000000001406f0 [ 46.922102] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 46.929661] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 46.937008] Call Trace: [ 46.939655] ? __ext4_get_inode_loc+0x392/0xf30 [ 46.944318] ? sb_init_dio_done_wq+0x80/0x80 [ 46.948800] ? __lock_acquire+0x2521/0x4620 [ 46.953113] ? save_trace+0x290/0x290 [ 46.956902] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 46.962725] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 46.968571] __blockdev_direct_IO+0xa1/0xca [ 46.973022] ? write_end_fn+0xa0/0xa0 [ 46.976988] ext4_direct_IO+0x70d/0x1890 [ 46.981605] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 46.987504] generic_file_direct_write+0x1e7/0x430 [ 46.992449] __generic_file_write_iter+0x2bc/0x5b0 [ 46.997750] ext4_file_write_iter+0x2ac/0xe90 [ 47.002821] ? ext4_file_mmap+0x2c0/0x2c0 [ 47.006968] ? __might_sleep+0x93/0xb0 [ 47.010851] do_iter_readv_writev+0x418/0x670 [ 47.015566] ? vfs_dedupe_file_range+0x8f0/0x8f0 [ 47.020587] ? rw_verify_area+0xea/0x2b0 [ 47.024724] do_iter_write+0x154/0x540 [ 47.028599] ? rcu_lockdep_current_cpu_online+0xf2/0x140 [ 47.034084] ? __kmalloc+0x376/0x7a0 [ 47.037875] vfs_iter_write+0x77/0xb0 [ 47.041774] iter_file_splice_write+0x572/0xad0 [ 47.046521] ? default_file_splice_read+0x7b0/0x7b0 [ 47.051748] ? __lock_is_held+0xb6/0x140 [ 47.055798] ? rcu_sync_lockdep_assert+0x6d/0xb0 [ 47.060695] ? __sb_start_write+0x153/0x2f0 [ 47.065005] ? default_file_splice_read+0x7b0/0x7b0 [ 47.070186] SyS_splice+0xd92/0x1430 [ 47.073891] ? do_sys_open+0x221/0x430 [ 47.077768] ? compat_SyS_vmsplice+0x250/0x250 [ 47.082364] ? do_syscall_64+0x53/0x640 [ 47.086323] ? compat_SyS_vmsplice+0x250/0x250 [ 47.090896] do_syscall_64+0x1e8/0x640 [ 47.094886] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 47.099716] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 47.105064] RIP: 0033:0x4402f9 [ 47.108242] RSP: 002b:00007ffdd1035868 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 47.116203] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004402f9 [ 47.123962] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 47.132392] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 47.140371] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b80 [ 47.148345] R13: 0000000000401c10 R14: 0000000000000000 R15: 0000000000000000 [ 47.155807] Code: 32 93 d8 ff e9 4a 1d 00 00 e8 b8 50 c1 ff 48 8b 84 24 f0 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 3d 54 00 00 48 8b 84 24 f0 00 00 00 4c 8b 60 [ 47.176093] RIP: do_blockdev_direct_IO+0x1c75/0x7fd0 RSP: ffff8880a8fc74c0 [ 47.183786] ---[ end trace 34fecd29fd5cea4d ]--- [ 47.188906] Kernel panic - not syncing: Fatal exception [ 47.196399] Kernel Offset: disabled [ 47.200300] Rebooting in 86400 seconds..