[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   30.859912] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   34.516597] random: sshd: uninitialized urandom read (32 bytes read)
[   35.005408] random: sshd: uninitialized urandom read (32 bytes read)
[   36.180693] random: sshd: uninitialized urandom read (32 bytes read)
[   38.647941] random: sshd: uninitialized urandom read (32 bytes read)
[   44.248737] random: sshd: uninitialized urandom read (32 bytes read)
[   44.271884] Not allocated shadow for addr ffff8801d3998000 (page ffffea000af59900)
[   44.279829] Attempted to access 270 bytes
[   44.284080] ------------[ cut here ]------------
[   44.288843] kernel BUG at mm/kmsan/kmsan.c:1341!
[   44.293609] invalid opcode: 0000 [#1] SMP PTI
[   44.298080] Dumping ftrace buffer:
[   44.301596]    (ftrace buffer empty)
[   44.305292] Modules linked in:
[   44.308491] CPU: 1 PID: 4515 Comm: sshd Not tainted 4.17.0-rc3+ #93
[   44.314877] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   44.324241] RIP: 0010:kmsan_get_shadow_address+0x1ce/0x1f0
[   44.329841] RSP: 0018:ffff880195ede700 EFLAGS: 00010082
[   44.335189] RAX: 000000000000001d RBX: 0000000000000740 RCX: 0000000000000000
[   44.342452] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
[   44.349718] RBP: ffff880195ede718 R08: 0000000000000000 R09: 0000000000000001
[   44.356976] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d3998000
[   44.364241] R13: 000000000000010e R14: 0000000000000001 R15: 000000000000010e
[   44.371514] FS:  00007f0b86bcc7c0(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000
[   44.379749] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   44.385635] CR2: 00007f0b86011100 CR3: 0000000194472000 CR4: 00000000001406e0
[   44.392909] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   44.400201] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   44.407546] Call Trace:
[   44.410139]  kmsan_internal_unpoison_shadow+0x5c/0xe0
[   44.415320]  kmsan_unpoison_shadow+0x66/0xb0
[   44.419746]  virtqueue_get_buf_ctx+0x742/0xa20
[   44.424323]  virtqueue_get_buf+0x72/0x90
[   44.428389]  start_xmit+0x293/0x29a0
[   44.432091]  ? packet_rcv+0x21a0/0x21a0
[   44.436059]  ? virtnet_close+0x2c0/0x2c0
[   44.440114]  dev_hard_start_xmit+0x5f1/0xc70
[   44.444536]  sch_direct_xmit+0x540/0x8f0
[   44.448581]  __qdisc_run+0x1785/0x3730
[   44.452466]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[   44.457819]  __dev_queue_xmit+0x1d50/0x3520
[   44.462134]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[   44.467499]  dev_queue_xmit+0x4b/0x60
[   44.471308]  ip_finish_output2+0x12a1/0x1470
[   44.475800]  ip_finish_output+0xcb2/0xff0
[   44.479952]  ip_output+0x505/0x5d0
[   44.483478]  ? ip_mc_finish_output+0x3b0/0x3b0
[   44.488051]  ? ip_finish_output+0xff0/0xff0
[   44.492365]  ip_queue_xmit+0x1a1e/0x1d10
[   44.496415]  ? __msan_metadata_ptr_for_store_1+0x13/0x20
[   44.501859]  ? __skb_clone+0x6ec/0x990
[   44.505736]  ? kmsan_set_origin+0x9e/0x160
[   44.509968]  ? ip_output+0x5d0/0x5d0
[   44.513664]  tcp_transmit_skb+0x3d81/0x53d0
[   44.517976]  tcp_write_xmit+0x2d71/0xb290
[   44.522121]  __tcp_push_pending_frames+0x124/0x3f0
[   44.527047]  tcp_push+0x8b6/0x9c0
[   44.530490]  tcp_sendmsg_locked+0x4e74/0x65a0
[   44.534975]  tcp_sendmsg+0xb2/0x100
[   44.538583]  ? tcp_sendmsg_locked+0x65a0/0x65a0
[   44.543244]  inet_sendmsg+0x48d/0x740
[   44.547030]  ? security_socket_sendmsg+0x91/0x1f0
[   44.551854]  ? inet_getname+0x4a0/0x4a0
[   44.555816]  sock_write_iter+0x3b9/0x470
[   44.559860]  ? sock_read_iter+0x480/0x480
[   44.564005]  __vfs_write+0x7fb/0x9f0
[   44.567711]  vfs_write+0x463/0x8d0
[   44.571247]  __x64_sys_write+0x1bf/0x3e0
[   44.575307]  do_syscall_64+0x154/0x220
[   44.579192]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   44.584364] RIP: 0033:0x7f0b84f67370
[   44.588062] RSP: 002b:00007ffc22fe4d78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   44.595774] RAX: ffffffffffffffda RBX: 0000000000000138 RCX: 00007f0b84f67370
[   44.603033] RDX: 0000000000000138 RSI: 0000557de39bc440 RDI: 0000000000000003
[   44.610307] RBP: 0000557de39bc440 R08: 0000557de39ba240 R09: 0000557de2159820
[   44.617561] R10: 000000000f7d158b R11: 0000000000000246 R12: 00007ffc22fe4ddc
[   44.624819] R13: 0000000000000001 R14: 0000557de39c24a0 R15: 0000000000000000
[   44.632074] Code: 75 29 48 c7 c7 84 fe 9f 8a 31 c0 e8 cd 29 83 ff 80 3c 25 f8 73 53 8b 00 75 11 48 c7 c7 b4 fe 9f 8a 31 c0 4c 89 fe e8 b2 29 83 ff <0f> 0b eb fe 48 3d ff ff ff 1f 0f 87 a2 fe ff ff 48 8b 1c 25 10 
[   44.651196] RIP: kmsan_get_shadow_address+0x1ce/0x1f0 RSP: ffff880195ede700
[   44.658386] ---[ end trace 9e9a4145864f0793 ]---
[   44.663137] Kernel panic - not syncing: Fatal exception in interrupt
[   44.670237] Dumping ftrace buffer:
[   44.673766]    (ftrace buffer empty)
[   44.677458] Kernel Offset: disabled
[   44.681064] Rebooting in 86400 seconds..