[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[   29.243890] random: sshd: uninitialized urandom read (32 bytes read)
[?25l[?1c7[ ok 8[?25h[?0c.

Debian GNU/Linux 7 syzkaller ttyS0

syzkaller login: [   33.671253] random: sshd: uninitialized urandom read (32 bytes read)
[   34.060218] random: sshd: uninitialized urandom read (32 bytes read)
[   35.270640] random: sshd: uninitialized urandom read (32 bytes read)
[   35.502129] random: sshd: uninitialized urandom read (32 bytes read)
Warning: Permanently added '10.128.0.61' (ECDSA) to the list of known hosts.
[   41.206956] random: sshd: uninitialized urandom read (32 bytes read)
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
executing program
[   41.339795] ==================================================================
[   41.347376] BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x754/0x1b70
[   41.354317] CPU: 1 PID: 4470 Comm: blkid Not tainted 4.17.0+ #9
[   41.360413] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   41.369888] Call Trace:
[   41.372489]  dump_stack+0x185/0x1d0
[   41.376128]  kmsan_report+0x188/0x2a0
[   41.379945]  kmsan_internal_check_memory+0x17e/0x1f0
[   41.385067]  ? _cond_resched+0x3c/0xd0
[   41.388966]  kmsan_copy_to_user+0x7a/0x160
[   41.393220]  copy_page_to_iter+0x754/0x1b70
[   41.397564]  generic_file_read_iter+0x2ef8/0x44d0
[   41.402437]  blkdev_read_iter+0x20d/0x280
[   41.406598]  ? blkdev_write_iter+0x5f0/0x5f0
[   41.411020]  __vfs_read+0x775/0x9d0
[   41.414693]  vfs_read+0x36c/0x6b0
[   41.418166]  __x64_sys_read+0x1bf/0x3e0
[   41.422143]  ? ksys_read+0x360/0x360
[   41.425861]  do_syscall_64+0x15b/0x230
[   41.429759]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   41.434948] RIP: 0033:0x7f6730a67310
[   41.438664] RSP: 002b:00007ffdbc8bd948 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[   41.446383] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6730a67310
[   41.453661] RDX: 0000000000000100 RSI: 000000000193cdf8 RDI: 0000000000000003
[   41.460935] RBP: 000000000193cdd0 R08: 0000000000000028 R09: 0000000001680000
[   41.468216] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000193c030
[   41.475580] R13: 0000000000000100 R14: 000000000193c080 R15: 000000000193cde8
[   41.482854] 
[   41.484485] Uninit was created at:
[   41.488044]  kmsan_alloc_meta_for_pages+0x161/0x3a0
[   41.493074]  kmsan_alloc_page+0x82/0xe0
[   41.497053]  __alloc_pages_nodemask+0xf7b/0x5cc0
[   41.501816]  alloc_pages_current+0x6b1/0x970
[   41.506238]  __page_cache_alloc+0x95/0x320
[   41.510485]  pagecache_get_page+0x52b/0x1450
[   41.514898]  grab_cache_page_write_begin+0x10d/0x190
[   41.520008]  block_write_begin+0xf9/0x3a0
[   41.524163]  blkdev_write_begin+0xf5/0x110
[   41.528408]  generic_perform_write+0x438/0x9d0
[   41.533006]  __generic_file_write_iter+0x43b/0xa10
[   41.537953]  blkdev_write_iter+0x3a8/0x5f0
[   41.542202]  do_iter_readv_writev+0x81c/0xa20
[   41.546798]  do_iter_write+0x30d/0xd50
[   41.550692]  do_pwritev+0x480/0x7a0
[   41.554327]  __x64_sys_pwritev+0x120/0x170
[   41.558567]  do_syscall_64+0x15b/0x230
[   41.562465]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   41.567648] 
[   41.569273] Bytes 4-255 of 256 are uninitialized
[   41.574113] Memory access starts at ffff8801c1bb7000
[   41.579202] ==================================================================
[   41.586558] Disabling lock debugging due to kernel taint
[   41.592011] Kernel panic - not syncing: panic_on_warn set ...
[   41.592011] 
[   41.599388] CPU: 1 PID: 4470 Comm: blkid Tainted: G    B             4.17.0+ #9
[   41.606842] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   41.616196] Call Trace:
[   41.618799]  dump_stack+0x185/0x1d0
[   41.622438]  panic+0x3d0/0x990
[   41.625648]  kmsan_report+0x29e/0x2a0
[   41.629457]  kmsan_internal_check_memory+0x17e/0x1f0
[   41.634567]  ? _cond_resched+0x3c/0xd0
[   41.638463]  kmsan_copy_to_user+0x7a/0x160
[   41.642710]  copy_page_to_iter+0x754/0x1b70
[   41.647051]  generic_file_read_iter+0x2ef8/0x44d0
[   41.651919]  blkdev_read_iter+0x20d/0x280
[   41.656086]  ? blkdev_write_iter+0x5f0/0x5f0
[   41.660510]  __vfs_read+0x775/0x9d0
[   41.664155]  vfs_read+0x36c/0x6b0
[   41.667619]  __x64_sys_read+0x1bf/0x3e0
[   41.671599]  ? ksys_read+0x360/0x360
[   41.675417]  do_syscall_64+0x15b/0x230
[   41.679317]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[   41.684504] RIP: 0033:0x7f6730a67310
[   41.688214] RSP: 002b:00007ffdbc8bd948 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
[   41.695923] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f6730a67310
[   41.703196] RDX: 0000000000000100 RSI: 000000000193cdf8 RDI: 0000000000000003
[   41.710472] RBP: 000000000193cdd0 R08: 0000000000000028 R09: 0000000001680000
[   41.717744] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000193c030
[   41.725021] R13: 0000000000000100 R14: 000000000193c080 R15: 000000000193cde8
[   41.732826] Dumping ftrace buffer:
[   41.736360]    (ftrace buffer empty)
[   41.740047] Kernel Offset: disabled
[   41.743651] Rebooting in 86400 seconds..