[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   28.979664] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   30.687225] random: sshd: uninitialized urandom read (32 bytes read)
[   31.006549] random: sshd: uninitialized urandom read (32 bytes read)
[   32.109966] random: sshd: uninitialized urandom read (32 bytes read)
[   32.308817] random: sshd: uninitialized urandom read (32 bytes read)
[   37.726181] random: sshd: uninitialized urandom read (32 bytes read)
[   37.746820] Not allocated shadow for addr ffff8801d3434000 (page ffffea000af39380)
[   37.754547] Attempted to access 270 bytes
[   37.758690] ------------[ cut here ]------------
[   37.763419] kernel BUG at mm/kmsan/kmsan.c:1344!
[   37.768165] invalid opcode: 0000 [#1] SMP PTI
[   37.772643] Dumping ftrace buffer:
[   37.776156]    (ftrace buffer empty)
[   37.779841] Modules linked in:
[   37.783011] CPU: 0 PID: 4517 Comm: sshd Not tainted 4.17.0-rc5+ #102
[   37.789482] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   37.798823] RIP: 0010:kmsan_get_shadow_address+0x1ce/0x1f0
[   37.804418] RSP: 0018:ffff8801993ce6f0 EFLAGS: 00010082
[   37.809754] RAX: 000000000000001d RBX: 0000000000000740 RCX: 0000000000000000
[   37.816999] RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000000
[   37.824247] RBP: ffff8801993ce708 R08: 0000000000000000 R09: 0000000000000001
[   37.831494] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801d3434000
[   37.838741] R13: 000000000000010e R14: 0000000000000001 R15: 000000000000010e
[   37.845997] FS:  00007f1af3a5d7c0(0000) GS:ffff88021fc00000(0000) knlGS:0000000000000000
[   37.854214] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   37.860078] CR2: 00007f1af3210fb0 CR3: 00000001c4e88000 CR4: 00000000001406f0
[   37.867326] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   37.874572] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   37.881820] Call Trace:
[   37.884398]  kmsan_internal_unpoison_shadow+0x5c/0xe0
[   37.889570]  kmsan_unpoison_shadow+0x66/0xb0
[   37.893961]  virtqueue_get_buf_ctx+0x73f/0xa20
[   37.898521]  virtqueue_get_buf+0x72/0x90
[   37.902560]  start_xmit+0x293/0x29b0
[   37.906252]  ? packet_rcv+0x21a0/0x21a0
[   37.910207]  ? virtnet_close+0x2c0/0x2c0
[   37.914249]  dev_hard_start_xmit+0x5f1/0xc70
[   37.918637]  sch_direct_xmit+0x578/0x8f0
[   37.922676]  __qdisc_run+0x1785/0x3730
[   37.926548]  __dev_queue_xmit+0x1d50/0x3510
[   37.930861]  dev_queue_xmit+0x4b/0x60
[   37.934645]  ip_finish_output2+0x12bf/0x1490
[   37.939038]  ip_finish_output+0xcaf/0xff0
[   37.943167]  ip_output+0x505/0x5d0
[   37.946684]  ? ip_mc_finish_output+0x3b0/0x3b0
[   37.951266]  ? ip_finish_output+0xff0/0xff0
[   37.955567]  ip_queue_xmit+0x1a1d/0x1d10
[   37.959780]  ? __msan_metadata_ptr_for_store_1+0x13/0x20
[   37.965206]  ? __skb_clone+0x6ec/0x990
[   37.969073]  ? kmsan_set_origin+0x9e/0x160
[   37.973287]  ? ip_output+0x5d0/0x5d0
[   37.976979]  tcp_transmit_skb+0x3d6d/0x53b0
[   37.981287]  tcp_write_xmit+0x2d71/0xb1f0
[   37.985426]  __tcp_push_pending_frames+0x124/0x400
[   37.990332]  tcp_push+0x803/0x8f0
[   37.993761]  tcp_sendmsg_locked+0x4eb1/0x6610
[   37.998252]  tcp_sendmsg+0xb2/0x100
[   38.001857]  ? tcp_sendmsg_locked+0x6610/0x6610
[   38.006503]  inet_sendmsg+0x3f7/0x750
[   38.010281]  ? __msan_metadata_ptr_for_load_8+0x10/0x20
[   38.015620]  ? inet_getname+0x4a0/0x4a0
[   38.019573]  sock_write_iter+0x3b7/0x470
[   38.023614]  ? sock_read_iter+0x480/0x480
[   38.027742]  __vfs_write+0x7fb/0x9f0
[   38.031437]  vfs_write+0x467/0x8c0
[   38.034957]  __x64_sys_write+0x1bf/0x3e0
[   38.038997]  do_syscall_64+0x152/0x230
[   38.042863]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   38.048027] RIP: 0033:0x7f1af1df8370
[   38.051712] RSP: 002b:00007fffc9894d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[   38.059408] RAX: ffffffffffffffda RBX: 0000000000000138 RCX: 00007f1af1df8370
[   38.066655] RDX: 0000000000000138 RSI: 000055fb00b00440 RDI: 0000000000000003
[   38.073902] RBP: 000055fb00b00440 R08: 000055fb00afe240 R09: 000055faffb11820
[   38.081146] R10: 0000000074c5c609 R11: 0000000000000246 R12: 00007fffc9894dac
[   38.088393] R13: 0000000000000001 R14: 000055fb00b064a0 R15: 0000000000000000
[   38.095639] Code: 75 29 48 c7 c7 83 00 a0 8a 31 c0 e8 7d 14 83 ff 80 3c 25 f8 73 53 8b 00 75 11 48 c7 c7 b3 00 a0 8a 31 c0 4c 89 fe e8 62 14 83 ff <0f> 0b eb fe 48 3d ff ff ff 1f 0f 87 a2 fe ff ff 48 8b 1c 25 10 
[   38.114722] RIP: kmsan_get_shadow_address+0x1ce/0x1f0 RSP: ffff8801993ce6f0
[   38.121799] ---[ end trace 1b025fd56ce2ff10 ]---
[   38.126528] Kernel panic - not syncing: Fatal exception in interrupt
[   38.133428] Dumping ftrace buffer:
[   38.136948]    (ftrace buffer empty)
[   38.140633] Kernel Offset: disabled
[   38.144239] Rebooting in 86400 seconds..