[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 35.356972] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 37.747549] random: sshd: uninitialized urandom read (32 bytes read) [ 38.143590] random: sshd: uninitialized urandom read (32 bytes read) [ 39.532930] random: sshd: uninitialized urandom read (32 bytes read) [ 39.768361] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.3' (ECDSA) to the list of known hosts. [ 45.279417] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 45.427151] ================================================================== [ 45.434554] BUG: KMSAN: kernel-infoleak in copy_from_read_buf+0x311/0x890 [ 45.441464] CPU: 0 PID: 4586 Comm: syz-executor982 Not tainted 4.17.0+ #22 [ 45.448455] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.457792] Call Trace: [ 45.460376] dump_stack+0x185/0x1d0 [ 45.463993] kmsan_report+0x188/0x2a0 [ 45.467799] kmsan_internal_check_memory+0x17e/0x1f0 [ 45.472891] kmsan_copy_to_user+0x73/0xb0 [ 45.477038] copy_from_read_buf+0x311/0x890 [ 45.481356] ? __msan_metadata_ptr_for_load_8+0x10/0x20 [ 45.486715] n_tty_read+0x178f/0x2f70 [ 45.490500] ? wait_woken+0x2e0/0x2e0 [ 45.494293] ? rcu_all_qs+0x32/0x1f0 [ 45.497995] ? _cond_resched+0x3c/0xd0 [ 45.501866] ? ldsem_down_read+0x95/0xad0 [ 45.506007] ? tty_ldisc_ref_wait+0x97/0xf0 [ 45.510334] ? n_tty_flush_buffer+0x430/0x430 [ 45.514825] tty_read+0x26e/0x6c0 [ 45.518271] ? release_one_tty+0x5f0/0x5f0 [ 45.522490] __vfs_read+0x1b2/0x9d0 [ 45.526108] vfs_read+0x36c/0x6b0 [ 45.529554] __x64_sys_read+0x1bf/0x3e0 [ 45.533515] ? ksys_read+0x360/0x360 [ 45.537220] do_syscall_64+0x15b/0x230 [ 45.541093] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 45.546277] RIP: 0033:0x445c89 [ 45.549458] RSP: 002b:00007f6c9e50bc48 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 45.557148] RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445c89 [ 45.564400] RDX: 00000000ffffff5c RSI: 0000000020000080 RDI: 0000000000000004 [ 45.571653] RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000 [ 45.578908] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 45.586173] R13: 00007ffee5b0dbbf R14: 00007f6c9e50c9c0 R15: 0000000000000001 [ 45.593441] [ 45.595054] Uninit was created at: [ 45.598591] kmsan_internal_alloc_meta_for_pages+0x146/0x700 [ 45.604379] kmsan_alloc_page+0x75/0xd0 [ 45.608337] __alloc_pages_nodemask+0xf7b/0x5cc0 [ 45.613074] alloc_pages_current+0x6b1/0x970 [ 45.617467] __vmalloc_node_range+0x8bf/0x1170 [ 45.622037] vmalloc+0xd8/0xf0 [ 45.625218] n_tty_open+0x4a/0x490 [ 45.628740] tty_ldisc_setup+0x375/0x670 [ 45.633147] tty_init_dev+0xb82/0x1020 [ 45.637023] ptmx_open+0x2bb/0x7c0 [ 45.640557] chrdev_open+0xc25/0xd90 [ 45.644255] do_dentry_open+0xccc/0x1440 [ 45.648304] vfs_open+0x1b6/0x2f0 [ 45.651746] path_openat+0x4771/0x6640 [ 45.655615] do_filp_open+0x261/0x640 [ 45.659395] do_sys_open+0x624/0x960 [ 45.663099] __x64_sys_openat+0x129/0x170 [ 45.667691] do_syscall_64+0x15b/0x230 [ 45.671566] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 45.676729] [ 45.678338] Byte 4094 of 4095 is uninitialized [ 45.683679] Memory access starts at ffffc900018af05e [ 45.688765] ================================================================== [ 45.696108] Disabling lock debugging due to kernel taint [ 45.701542] Kernel panic - not syncing: panic_on_warn set ... [ 45.701542] [ 45.708903] CPU: 0 PID: 4586 Comm: syz-executor982 Tainted: G B 4.17.0+ #22 [ 45.717291] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.726628] Call Trace: [ 45.729204] dump_stack+0x185/0x1d0 [ 45.732820] panic+0x3d0/0x9b0 [ 45.736015] kmsan_report+0x29e/0x2a0 [ 45.739823] kmsan_internal_check_memory+0x17e/0x1f0 [ 45.745014] kmsan_copy_to_user+0x73/0xb0 [ 45.749159] copy_from_read_buf+0x311/0x890 [ 45.753465] ? __msan_metadata_ptr_for_load_8+0x10/0x20 [ 45.758821] n_tty_read+0x178f/0x2f70 [ 45.762623] ? wait_woken+0x2e0/0x2e0 [ 45.766413] ? rcu_all_qs+0x32/0x1f0 [ 45.770114] ? _cond_resched+0x3c/0xd0 [ 45.773990] ? ldsem_down_read+0x95/0xad0 [ 45.778136] ? tty_ldisc_ref_wait+0x97/0xf0 [ 45.782443] ? n_tty_flush_buffer+0x430/0x430 [ 45.786932] tty_read+0x26e/0x6c0 [ 45.790382] ? release_one_tty+0x5f0/0x5f0 [ 45.794616] __vfs_read+0x1b2/0x9d0 [ 45.798240] vfs_read+0x36c/0x6b0 [ 45.801684] __x64_sys_read+0x1bf/0x3e0 [ 45.805647] ? ksys_read+0x360/0x360 [ 45.809349] do_syscall_64+0x15b/0x230 [ 45.813228] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 45.818403] RIP: 0033:0x445c89 [ 45.821582] RSP: 002b:00007f6c9e50bc48 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 45.829271] RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445c89 [ 45.836522] RDX: 00000000ffffff5c RSI: 0000000020000080 RDI: 0000000000000004 [ 45.843773] RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000 [ 45.851044] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 45.858404] R13: 00007ffee5b0dbbf R14: 00007f6c9e50c9c0 R15: 0000000000000001 [ 45.866254] Dumping ftrace buffer: [ 45.869779] (ftrace buffer empty) [ 45.873561] Kernel Offset: disabled [ 45.877181] Rebooting in 86400 seconds..