[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 34.783116] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 39.628563] random: sshd: uninitialized urandom read (32 bytes read) [ 40.090885] random: sshd: uninitialized urandom read (32 bytes read) [ 41.366717] random: sshd: uninitialized urandom read (32 bytes read) [ 41.603531] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.28' (ECDSA) to the list of known hosts. [ 47.146978] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program [ 47.372096] ================================================================== [ 47.379553] BUG: KMSAN: kernel-infoleak in copy_from_read_buf+0x311/0x890 [ 47.386485] CPU: 0 PID: 4599 Comm: syz-executor383 Not tainted 4.17.0+ #22 [ 47.393489] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.402836] Call Trace: [ 47.405436] dump_stack+0x185/0x1d0 [ 47.409077] kmsan_report+0x188/0x2a0 [ 47.412914] kmsan_internal_check_memory+0x138/0x1f0 [ 47.418006] kmsan_copy_to_user+0x73/0xb0 executing program [ 47.422154] copy_from_read_buf+0x311/0x890 [ 47.426474] ? __msan_metadata_ptr_for_load_8+0x10/0x20 [ 47.431875] n_tty_read+0x178f/0x2f70 [ 47.435686] ? wait_woken+0x2e0/0x2e0 [ 47.439478] ? rcu_all_qs+0x32/0x1f0 [ 47.443197] ? _cond_resched+0x3c/0xd0 [ 47.447087] ? ldsem_down_read+0x95/0xad0 [ 47.451240] ? tty_ldisc_ref_wait+0x97/0xf0 [ 47.455563] ? n_tty_flush_buffer+0x430/0x430 [ 47.460051] tty_read+0x26e/0x6c0 [ 47.463491] ? release_one_tty+0x5f0/0x5f0 [ 47.467735] __vfs_read+0x1b2/0x9d0 executing program [ 47.471388] vfs_read+0x36c/0x6b0 [ 47.474856] __x64_sys_read+0x1bf/0x3e0 [ 47.478859] ? ksys_read+0x360/0x360 [ 47.482587] do_syscall_64+0x15b/0x230 [ 47.486477] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 47.491682] RIP: 0033:0x4456a9 [ 47.494855] RSP: 002b:00007f7dd9282d18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 47.502557] RAX: ffffffffffffffda RBX: 00000000006dac6c RCX: 00000000004456a9 [ 47.509826] RDX: 00000000ffffff5c RSI: 0000000020000080 RDI: 0000000000000008 executing program executing program [ 47.517097] RBP: 00000000006dac68 R08: 0000000000000000 R09: 0000000000000000 [ 47.524348] R10: 0000000000000000 R11: 0000000000000246 R12: 6d74702f7665642f [ 47.531617] R13: 00007ffee794ad0f R14: 00007f7dd92839c0 R15: 0000000000000001 [ 47.538908] [ 47.540527] Uninit was created at: [ 47.544057] kmsan_internal_alloc_meta_for_pages+0x146/0x700 [ 47.549863] kmsan_alloc_page+0x75/0xd0 [ 47.553856] __alloc_pages_nodemask+0xf7b/0x5cc0 [ 47.558635] alloc_pages_current+0x6b1/0x970 [ 47.563032] __vmalloc_node_range+0x8bf/0x1170 [ 47.567608] vmalloc+0xd8/0xf0 executing program [ 47.570806] n_tty_open+0x4a/0x490 [ 47.574349] tty_ldisc_setup+0x375/0x670 [ 47.578393] tty_init_dev+0xb82/0x1020 [ 47.582272] ptmx_open+0x2bb/0x7c0 [ 47.585801] chrdev_open+0xc25/0xd90 [ 47.589499] do_dentry_open+0xccc/0x1440 [ 47.593582] vfs_open+0x1b6/0x2f0 [ 47.597047] path_openat+0x4771/0x6640 [ 47.600967] do_filp_open+0x261/0x640 [ 47.604749] do_sys_open+0x624/0x960 [ 47.608453] __x64_sys_openat+0x129/0x170 [ 47.612607] do_syscall_64+0x15b/0x230 [ 47.616512] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 47.621692] [ 47.623300] Byte 4082 of 4093 is uninitialized [ 47.627870] Memory access starts at ffffc900018e705e [ 47.632957] ================================================================== [ 47.640342] Disabling lock debugging due to kernel taint [ 47.645785] Kernel panic - not syncing: panic_on_warn set ... [ 47.645785] [ 47.653149] CPU: 0 PID: 4599 Comm: syz-executor383 Tainted: G B 4.17.0+ #22 [ 47.661544] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 47.670889] Call Trace: [ 47.673485] dump_stack+0x185/0x1d0 [ 47.677133] panic+0x3d0/0x9b0 [ 47.680338] kmsan_report+0x29e/0x2a0 [ 47.684127] kmsan_internal_check_memory+0x138/0x1f0 [ 47.689233] kmsan_copy_to_user+0x73/0xb0 [ 47.693415] copy_from_read_buf+0x311/0x890 [ 47.697752] ? __msan_metadata_ptr_for_load_8+0x10/0x20 [ 47.703111] n_tty_read+0x178f/0x2f70 [ 47.706913] ? wait_woken+0x2e0/0x2e0 [ 47.710720] ? rcu_all_qs+0x32/0x1f0 [ 47.714440] ? _cond_resched+0x3c/0xd0 [ 47.718327] ? ldsem_down_read+0x95/0xad0 [ 47.722484] ? tty_ldisc_ref_wait+0x97/0xf0 [ 47.726799] ? n_tty_flush_buffer+0x430/0x430 [ 47.731292] tty_read+0x26e/0x6c0 [ 47.734761] ? release_one_tty+0x5f0/0x5f0 [ 47.738992] __vfs_read+0x1b2/0x9d0 [ 47.742618] vfs_read+0x36c/0x6b0 [ 47.746058] __x64_sys_read+0x1bf/0x3e0 [ 47.750019] ? ksys_read+0x360/0x360 [ 47.753721] do_syscall_64+0x15b/0x230 [ 47.757617] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 47.762805] RIP: 0033:0x4456a9 [ 47.765977] RSP: 002b:00007f7dd9282d18 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 47.773676] RAX: ffffffffffffffda RBX: 00000000006dac6c RCX: 00000000004456a9 [ 47.781031] RDX: 00000000ffffff5c RSI: 0000000020000080 RDI: 0000000000000008 [ 47.788283] RBP: 00000000006dac68 R08: 0000000000000000 R09: 0000000000000000 [ 47.795538] R10: 0000000000000000 R11: 0000000000000246 R12: 6d74702f7665642f [ 47.802815] R13: 00007ffee794ad0f R14: 00007f7dd92839c0 R15: 0000000000000001 [ 47.810708] Dumping ftrace buffer: [ 47.814235] (ftrace buffer empty) [ 47.817923] Kernel Offset: disabled [ 47.821538] Rebooting in 86400 seconds..