[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 28.430685] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 32.563299] random: sshd: uninitialized urandom read (32 bytes read) [ 32.974991] random: sshd: uninitialized urandom read (32 bytes read) [ 34.181328] random: sshd: uninitialized urandom read (32 bytes read) [ 34.399326] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.29' (ECDSA) to the list of known hosts. [ 39.974576] 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 executing program executing program executing program executing program [ 40.165175] ================================================================== [ 40.172588] BUG: KMSAN: kernel-infoleak in copy_page_to_iter+0x754/0x1b70 [ 40.179525] CPU: 0 PID: 4516 Comm: blkid Not tainted 4.17.0+ #9 [ 40.185578] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.194931] Call Trace: [ 40.197526] dump_stack+0x185/0x1d0 [ 40.201157] kmsan_report+0x188/0x2a0 [ 40.204966] kmsan_internal_check_memory+0x17e/0x1f0 [ 40.210080] ? _cond_resched+0x3c/0xd0 [ 40.213985] kmsan_copy_to_user+0x7a/0x160 [ 40.218228] copy_page_to_iter+0x754/0x1b70 [ 40.222572] generic_file_read_iter+0x2ef8/0x44d0 [ 40.227434] blkdev_read_iter+0x20d/0x280 [ 40.231599] ? blkdev_write_iter+0x5f0/0x5f0 [ 40.236008] __vfs_read+0x775/0x9d0 [ 40.239633] vfs_read+0x36c/0x6b0 [ 40.243093] __x64_sys_read+0x1bf/0x3e0 [ 40.247073] ? ksys_read+0x360/0x360 [ 40.250786] do_syscall_64+0x15b/0x230 [ 40.254684] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 40.259869] RIP: 0033:0x7fdeff68f310 [ 40.263578] RSP: 002b:00007ffe999660b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 40.271288] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdeff68f310 [ 40.278561] RDX: 0000000000000100 RSI: 0000000001e78df8 RDI: 0000000000000003 [ 40.285833] RBP: 0000000001e78dd0 R08: 0000000000000028 R09: 0000000001680000 [ 40.293104] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001e78030 [ 40.300386] R13: 0000000000000100 R14: 0000000001e78080 R15: 0000000001e78de8 [ 40.307665] [ 40.309291] Uninit was created at: [ 40.312838] kmsan_alloc_meta_for_pages+0x161/0x3a0 [ 40.317865] kmsan_alloc_page+0x82/0xe0 [ 40.321839] __alloc_pages_nodemask+0xf7b/0x5cc0 [ 40.326620] alloc_pages_current+0x6b1/0x970 [ 40.331049] __page_cache_alloc+0x95/0x320 [ 40.335286] pagecache_get_page+0x52b/0x1450 [ 40.339700] grab_cache_page_write_begin+0x10d/0x190 [ 40.344809] block_write_begin+0xf9/0x3a0 [ 40.348963] blkdev_write_begin+0xf5/0x110 [ 40.353213] generic_perform_write+0x438/0x9d0 [ 40.357811] __generic_file_write_iter+0x43b/0xa10 [ 40.362748] blkdev_write_iter+0x3a8/0x5f0 [ 40.366987] do_iter_readv_writev+0x81c/0xa20 [ 40.371484] do_iter_write+0x30d/0xd50 [ 40.375381] do_writev+0x3be/0x820 [ 40.378922] __x64_sys_writev+0xe1/0x120 [ 40.382986] do_syscall_64+0x15b/0x230 [ 40.386878] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 40.392055] [ 40.393675] Bytes 4-255 of 256 are uninitialized [ 40.398421] Memory access starts at ffff8801b9903000 [ 40.403514] ================================================================== [ 40.410862] Disabling lock debugging due to kernel taint [ 40.416302] Kernel panic - not syncing: panic_on_warn set ... [ 40.416302] [ 40.423675] CPU: 0 PID: 4516 Comm: blkid Tainted: G B 4.17.0+ #9 [ 40.431118] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 40.440529] Call Trace: [ 40.443121] dump_stack+0x185/0x1d0 [ 40.446749] panic+0x3d0/0x990 [ 40.449950] kmsan_report+0x29e/0x2a0 [ 40.453752] kmsan_internal_check_memory+0x17e/0x1f0 [ 40.458865] ? _cond_resched+0x3c/0xd0 [ 40.462766] kmsan_copy_to_user+0x7a/0x160 [ 40.467006] copy_page_to_iter+0x754/0x1b70 [ 40.471343] generic_file_read_iter+0x2ef8/0x44d0 [ 40.476203] blkdev_read_iter+0x20d/0x280 [ 40.480364] ? blkdev_write_iter+0x5f0/0x5f0 [ 40.484776] __vfs_read+0x775/0x9d0 [ 40.488411] vfs_read+0x36c/0x6b0 [ 40.491868] __x64_sys_read+0x1bf/0x3e0 [ 40.495848] ? ksys_read+0x360/0x360 [ 40.499565] do_syscall_64+0x15b/0x230 [ 40.503458] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 40.508647] RIP: 0033:0x7fdeff68f310 [ 40.512354] RSP: 002b:00007ffe999660b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 40.520066] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fdeff68f310 [ 40.527344] RDX: 0000000000000100 RSI: 0000000001e78df8 RDI: 0000000000000003 [ 40.534613] RBP: 0000000001e78dd0 R08: 0000000000000028 R09: 0000000001680000 [ 40.541887] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000001e78030 [ 40.549156] R13: 0000000000000100 R14: 0000000001e78080 R15: 0000000001e78de8 [ 40.556865] Dumping ftrace buffer: [ 40.560387] (ftrace buffer empty) [ 40.564070] Kernel Offset: disabled [ 40.567673] Rebooting in 86400 seconds..