[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 31.657703] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 36.153628] random: sshd: uninitialized urandom read (32 bytes read) [ 36.735661] random: sshd: uninitialized urandom read (32 bytes read) [ 37.857947] random: sshd: uninitialized urandom read (32 bytes read) [ 38.073453] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.28' (ECDSA) to the list of known hosts. [ 43.706759] 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 executing program executing program executing program executing program executing program executing program executing program [ 43.906929] ================================================================== [ 43.914366] BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x754/0x1b70 [ 43.921317] CPU: 0 PID: 4533 Comm: blkid Not tainted 4.17.0+ #9 [ 43.927381] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.936749] Call Trace: [ 43.939367] dump_stack+0x185/0x1d0 [ 43.944929] kmsan_report+0x188/0x2a0 [ 43.948776] kmsan_internal_check_memory+0x17e/0x1f0 executing program executing program executing program executing program executing program executing program executing program executing program [ 43.953910] ? _cond_resched+0x3c/0xd0 [ 43.957823] kmsan_copy_to_user+0x7a/0x160 [ 43.962086] copy_page_to_iter+0x754/0x1b70 [ 43.966449] generic_file_read_iter+0x2ef8/0x44d0 [ 43.971319] blkdev_read_iter+0x20d/0x280 [ 43.975491] ? blkdev_write_iter+0x5f0/0x5f0 [ 43.979926] __vfs_read+0x775/0x9d0 [ 43.983585] vfs_read+0x36c/0x6b0 [ 43.987121] __x64_sys_read+0x1bf/0x3e0 [ 43.991116] ? ksys_read+0x360/0x360 [ 43.994855] do_syscall_64+0x15b/0x230 [ 43.998775] entry_SYSCALL_64_after_hwframe+0x44/0xa9 executing program executing program executing program executing program executing program executing program executing program executing program [ 44.003974] RIP: 0033:0x7fc139011310 [ 44.007696] RSP: 002b:00007ffecd6f1018 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 44.015427] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc139011310 [ 44.022708] RDX: 0000000000000100 RSI: 00000000017ffdf8 RDI: 0000000000000003 [ 44.029981] RBP: 00000000017ffdd0 R08: 0000000000000028 R09: 0000000001680000 [ 44.037696] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000017ff030 [ 44.045006] R13: 0000000000000100 R14: 00000000017ff080 R15: 00000000017ffde8 [ 44.052305] [ 44.054002] Uninit was created at: executing program executing program executing program executing program executing program executing program executing program [ 44.057578] kmsan_alloc_meta_for_pages+0x161/0x3a0 [ 44.062616] kmsan_alloc_page+0x82/0xe0 [ 44.066615] __alloc_pages_nodemask+0xf7b/0x5cc0 [ 44.071418] alloc_pages_current+0x6b1/0x970 [ 44.075870] __page_cache_alloc+0x95/0x320 [ 44.080221] pagecache_get_page+0x52b/0x1450 [ 44.084661] grab_cache_page_write_begin+0x10d/0x190 [ 44.089774] block_write_begin+0xf9/0x3a0 [ 44.093947] blkdev_write_begin+0xf5/0x110 [ 44.098234] generic_perform_write+0x438/0x9d0 [ 44.102839] __generic_file_write_iter+0x43b/0xa10 executing program executing program executing program executing program executing program executing program executing program executing program [ 44.107793] blkdev_write_iter+0x3a8/0x5f0 [ 44.112066] do_iter_readv_writev+0x81c/0xa20 [ 44.116606] do_iter_write+0x30d/0xd50 [ 44.120524] do_pwritev+0x480/0x7a0 [ 44.124184] __x64_sys_pwritev+0x120/0x170 [ 44.128450] do_syscall_64+0x15b/0x230 [ 44.132368] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.137569] [ 44.139202] Bytes 4-255 of 256 are uninitialized [ 44.143964] Memory access starts at ffff8801c6718000 [ 44.149066] ================================================================== executing program executing program executing program executing program executing program executing program executing program [ 44.156451] Disabling lock debugging due to kernel taint [ 44.161911] Kernel panic - not syncing: panic_on_warn set ... [ 44.161911] [ 44.169299] CPU: 0 PID: 4533 Comm: blkid Tainted: G B 4.17.0+ #9 [ 44.176785] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.186152] Call Trace: [ 44.188785] dump_stack+0x185/0x1d0 [ 44.192448] panic+0x3d0/0x990 [ 44.195775] kmsan_report+0x29e/0x2a0 [ 44.199622] kmsan_internal_check_memory+0x17e/0x1f0 executing program executing program executing program executing program executing program executing program executing program executing program [ 44.204760] ? _cond_resched+0x3c/0xd0 [ 44.208668] kmsan_copy_to_user+0x7a/0x160 [ 44.212928] copy_page_to_iter+0x754/0x1b70 [ 44.217286] generic_file_read_iter+0x2ef8/0x44d0 [ 44.222282] blkdev_read_iter+0x20d/0x280 [ 44.226465] ? blkdev_write_iter+0x5f0/0x5f0 [ 44.230901] __vfs_read+0x775/0x9d0 [ 44.234570] vfs_read+0x36c/0x6b0 [ 44.238067] __x64_sys_read+0x1bf/0x3e0 [ 44.242074] ? ksys_read+0x360/0x360 [ 44.245829] do_syscall_64+0x15b/0x230 [ 44.249752] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.254971] RIP: 0033:0x7fc139011310 executing program executing program executing program executing program executing program executing program executing program [ 44.258689] RSP: 002b:00007ffecd6f1018 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 44.266403] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fc139011310 [ 44.273672] RDX: 0000000000000100 RSI: 00000000017ffdf8 RDI: 0000000000000003 [ 44.280989] RBP: 00000000017ffdd0 R08: 0000000000000028 R09: 0000000001680000 [ 44.288371] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000017ff030 [ 44.295671] R13: 0000000000000100 R14: 00000000017ff080 R15: 00000000017ffde8 [ 44.303561] Dumping ftrace buffer: [ 44.307097] (ftrace buffer empty) [ 44.310788] Kernel Offset: disabled [ 44.314395] Rebooting in 86400 seconds..