[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   29.643653] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   33.004260] random: sshd: uninitialized urandom read (32 bytes read)
[   33.338345] random: sshd: uninitialized urandom read (32 bytes read)
[   34.466348] random: sshd: uninitialized urandom read (32 bytes read)
[   34.680704] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.0.52' (ECDSA) to the list of known hosts.
[   40.143695] random: sshd: uninitialized urandom read (32 bytes read)
executing program
[   40.316254] Not allocated shadow for addr ffff88021f920000 (page ffffea000cbd6c00)
[   40.323980] Attempted to access 4096 bytes
[   40.328212] ------------[ cut here ]------------
[   40.332941] kernel BUG at mm/kmsan/kmsan.c:1378!
[   40.337677] invalid opcode: 0000 [#1] SMP PTI
[   40.342144] Dumping ftrace buffer:
[   40.345654]    (ftrace buffer empty)
[   40.349339] Modules linked in:
[   40.352512] CPU: 1 PID: 4527 Comm: syz-executor823 Not tainted 4.17.0+ #6
[   40.359411] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   40.368763] RIP: 0010:kmsan_get_shadow_address+0x1ce/0x1f0
[   40.374361] RSP: 0018:ffff8801aee4f360 EFLAGS: 00010082
[   40.379699] RAX: 000000000000001e RBX: 0000000000000860 RCX: 0000000000000000
[   40.386946] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
[   40.394194] RBP: ffff8801aee4f378 R08: 0000000000000000 R09: 0000000000000001
[   40.401442] R10: 0000000000000000 R11: ffffffff865757b0 R12: ffff88021f920000
[   40.408692] R13: 000000000018b000 R14: 0000000000000001 R15: 0000000000001000
[   40.415943] FS:  00007effc83c3700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
[   40.424172] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   40.430030] CR2: 00007effc83c2e78 CR3: 000000019ffb6000 CR4: 00000000001406e0
[   40.437276] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   40.444522] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   40.451765] Call Trace:
[   40.454349]  kmsan_internal_unpoison_shadow+0x5c/0xe0
[   40.459520]  kmsan_unpoison_shadow+0x66/0xb0
[   40.463904]  get_user_pages_fast+0x493/0x770
[   40.468295]  iov_iter_get_pages+0x465/0x1810
[   40.472691]  ? kmsan_set_origin_inline+0x6b/0x120
[   40.477523]  ? blkdev_direct_IO+0x1252/0x2d90
[   40.481998]  bio_iov_iter_get_pages+0x1c6/0xc70
[   40.486645]  blkdev_direct_IO+0x1252/0x2d90
[   40.490949]  ? do_io_submit+0x2fb0/0x2fb0
[   40.495078]  ? touch_atime+0x227/0x530
[   40.498946]  ? blkdev_read_iter+0x20d/0x280
[   40.503245]  ? blkdev_releasepage+0x210/0x210
[   40.507720]  generic_file_read_iter+0x3c6d/0x44d0
[   40.512541]  ? __fsnotify_parent+0x75/0x560
[   40.516845]  ? __fsnotify_parent+0x9d/0x560
[   40.521161]  blkdev_read_iter+0x20d/0x280
[   40.525289]  ? blkdev_write_iter+0x5f0/0x5f0
[   40.529678]  aio_read+0x5c6/0x720
[   40.533123]  ? __msan_metadata_ptr_for_load_1+0x10/0x20
[   40.538470]  ? fget+0x42c/0x470
[   40.541730]  do_io_submit+0x1cbf/0x2fb0
[   40.545691]  __x64_sys_io_submit+0xda/0x110
[   40.549992]  ? __ia32_sys_io_destroy+0x70/0x70
[   40.554551]  do_syscall_64+0x15b/0x230
[   40.558425]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   40.563592] RIP: 0033:0x445939
[   40.566767] RSP: 002b:00007effc83c2da8 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
[   40.574451] RAX: ffffffffffffffda RBX: 00000000006dac74 RCX: 0000000000445939
[   40.581706] RDX: 0000000020001540 RSI: 0000000000000001 RDI: 00007effc83e5000
[   40.589294] RBP: 00000000006dac70 R08: 0000000000000000 R09: 0000000000000000
[   40.596542] R10: 0000000000000000 R11: 0000000000000246 R12: 6c756e2f7665642f
[   40.603791] R13: 7363762f7665642f R14: fffffffffffff189 R15: 0000000000000009
[   40.611039] Code: 75 29 48 c7 c7 59 38 97 8a 31 c0 e8 fd 4c 80 ff 80 3c 25 f8 93 53 8b 00 75 11 48 c7 c7 89 38 97 8a 31 c0 4c 89 fe e8 e2 4c 80 ff <0f> 0b eb fe 48 3d ff ff ff 1f 0f 87 a2 fe ff ff 48 8b 1c 25 10 
[   40.630123] RIP: kmsan_get_shadow_address+0x1ce/0x1f0 RSP: ffff8801aee4f360
[   40.637199] ---[ end trace 361a59d8f13869c5 ]---
[   40.641929] Kernel panic - not syncing: Fatal exception
[   40.647875] Dumping ftrace buffer:
[   40.651399]    (ftrace buffer empty)
[   40.655082] Kernel Offset: disabled
[   40.658686] Rebooting in 86400 seconds..