[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 12.880955] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.523618] random: sshd: uninitialized urandom read (32 bytes read) [ 17.701931] random: sshd: uninitialized urandom read (32 bytes read) [ 18.564215] random: sshd: uninitialized urandom read (32 bytes read) [ 39.284123] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.17' (ECDSA) to the list of known hosts. [ 44.717143] 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 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 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 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 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 [ 48.937284] ================================================================== [ 48.944906] BUG: KASAN: out-of-bounds in __unwind_start+0x37c/0x3c0 [ 48.951298] Read of size 8 at addr ffff8801d8407830 by task syz-executor931/4282 [ 48.959153] [ 48.960777] CPU: 0 PID: 4282 Comm: syz-executor931 Not tainted 4.9.105-gd7e64f8 #40 [ 48.968602] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.977950] ffff8801d8b77140 ffffffff81eb41a9 ffffea00076101c0 ffff8801d8407830 [ 48.985975] 0000000000000000 ffff8801d8407838 ffff8801d8b77278 ffff8801d8b77178 [ 48.994023] ffffffff81567e49 ffff8801d8407830 0000000000000008 0000000000000000 [ 49.002039] Call Trace: [ 49.004606] [] dump_stack+0xc1/0x128 [ 49.009958] [] print_address_description+0x6c/0x234 [ 49.016628] [] kasan_report.cold.6+0x242/0x2fe [ 49.022860] [] ? __unwind_start+0x37c/0x3c0 [ 49.028830] [] __asan_report_load8_noabort+0x14/0x20 [ 49.035588] [] __unwind_start+0x37c/0x3c0 [ 49.041390] [] ? ptrace_may_access+0x24/0x50 [ 49.047437] [] __save_stack_trace+0x59/0xf0 [ 49.053417] [] save_stack_trace_tsk+0x48/0x70 [ 49.059578] [] proc_pid_stack+0x148/0x220 [ 49.065389] [] ? lock_trace+0xc0/0xc0 [ 49.070863] [] proc_single_show+0xfd/0x170 [ 49.077037] [] seq_read+0x4b6/0x12e0 [ 49.082399] [] ? seq_dentry+0x290/0x290 [ 49.088787] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 49.097269] [] ? fsnotify+0x1100/0x1100 [ 49.102891] [] do_loop_readv_writev.part.18+0xd5/0x280 [ 49.109811] [] do_readv_writev+0x565/0x7a0 [ 49.115702] [] ? vfs_write+0x530/0x530 [ 49.121249] [] ? kasan_unpoison_shadow+0x35/0x50 [ 49.127651] [] ? push_pipe+0x3f4/0x780 [ 49.133251] [] ? iov_iter_get_pages_alloc+0x2bb/0xf10 [ 49.140177] [] vfs_readv+0x84/0xc0 [ 49.145382] [] default_file_splice_read+0x44b/0x7e0 [ 49.152057] [] ? depot_save_stack+0x132/0x460 [ 49.158220] [] ? do_splice_direct+0x270/0x270 [ 49.164409] [] ? save_stack_trace+0x16/0x20 [ 49.170378] [] ? kasan_kmalloc+0xc7/0xe0 [ 49.176709] [] ? __kmalloc+0x11d/0x300 [ 49.182254] [] ? alloc_pipe_info+0x164/0x380 [ 49.188339] [] ? splice_direct_to_actor+0x62c/0x7e0 [ 49.195027] [] ? do_splice_direct+0x1a3/0x270 [ 49.201184] [] ? do_sendfile+0x4f0/0xc60 [ 49.206902] [] ? SyS_sendfile64+0xd1/0x160 [ 49.212780] [] ? entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 49.219881] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 49.228363] [] ? fsnotify+0x1100/0x1100 [ 49.233989] [] ? avc_policy_seqno+0x9/0x20 [ 49.239897] [] ? selinux_file_permission+0x82/0x470 [ 49.246569] [] ? security_file_permission+0x8f/0x1f0 [ 49.253303] [] ? do_splice_direct+0x270/0x270 [ 49.259455] [] do_splice_to+0x10c/0x170 [ 49.265082] [] splice_direct_to_actor+0x23f/0x7e0 [ 49.271600] [] ? pipe_to_sendpage+0x330/0x330 [ 49.277738] [] ? do_splice_to+0x170/0x170 [ 49.283520] [] ? security_file_permission+0x8f/0x1f0 [ 49.290441] [] ? rw_verify_area+0xe5/0x2b0 [ 49.296311] [] do_splice_direct+0x1a3/0x270 [ 49.302280] [] ? splice_direct_to_actor+0x7e0/0x7e0 [ 49.308945] [] ? rcu_sync_lockdep_assert+0x73/0xb0 [ 49.315524] [] ? __sb_start_write+0x161/0x300 [ 49.321742] [] do_sendfile+0x4f0/0xc60 [ 49.327271] [] ? do_compat_pwritev64+0x180/0x180 [ 49.333674] [] ? __might_fault+0x114/0x1d0 [ 49.339631] [] SyS_sendfile64+0xd1/0x160 [ 49.345318] [] ? SyS_sendfile+0x160/0x160 [ 49.351109] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 49.357940] [] ? do_syscall_64+0x48/0x490 [ 49.363726] [] ? SyS_sendfile+0x160/0x160 [ 49.369512] [] do_syscall_64+0x1a6/0x490 [ 49.375206] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 49.382103] [ 49.383705] The buggy address belongs to the page: [ 49.388626] page:ffffea00076101c0 count:0 mapcount:0 mapping: (null) index:0x0 [ 49.396886] flags: 0x8000000000000000() [ 49.400834] page dumped because: kasan: bad access detected [ 49.406523] [ 49.408135] Memory state around the buggy address: [ 49.413041] ffff8801d8407700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 49.420475] ffff8801d8407780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 49.427826] >ffff8801d8407800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 49.435186] ^ [ 49.440366] ffff8801d8407880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 49.447710] ffff8801d8407900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 49.455064] ================================================================== [ 49.462414] Disabling lock debugging due to kernel taint [ 49.468029] Kernel panic - not syncing: panic_on_warn set ... [ 49.468029] [ 49.475384] CPU: 0 PID: 4282 Comm: syz-executor931 Tainted: G B 4.9.105-gd7e64f8 #40 [ 49.484485] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.493830] ffff8801d8b770a0 ffffffff81eb41a9 ffffffff843c625d 00000000ffffffff [ 49.501830] 0000000000000000 0000000000000000 ffff8801d8b77278 ffff8801d8b77160 [ 49.509842] ffffffff81421e15 0000000041b58ab3 ffffffff843b9990 ffffffff81421c56 [ 49.517829] Call Trace: [ 49.520401] [] dump_stack+0xc1/0x128 [ 49.525750] [] panic+0x1bf/0x3bc [ 49.530769] [] ? add_taint.cold.6+0x16/0x16 [ 49.536725] [] ? ___preempt_schedule+0x16/0x18 [ 49.542937] [] kasan_end_report+0x47/0x4f [ 49.548725] [] kasan_report.cold.6+0x76/0x2fe [ 49.554871] [] ? __unwind_start+0x37c/0x3c0 [ 49.560856] [] __asan_report_load8_noabort+0x14/0x20 [ 49.567618] [] __unwind_start+0x37c/0x3c0 [ 49.573406] [] ? ptrace_may_access+0x24/0x50 [ 49.579470] [] __save_stack_trace+0x59/0xf0 [ 49.585477] [] save_stack_trace_tsk+0x48/0x70 [ 49.591636] [] proc_pid_stack+0x148/0x220 [ 49.597446] [] ? lock_trace+0xc0/0xc0 [ 49.602920] [] proc_single_show+0xfd/0x170 [ 49.608921] [] seq_read+0x4b6/0x12e0 [ 49.614301] [] ? seq_dentry+0x290/0x290 [ 49.619913] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 49.628477] [] ? fsnotify+0x1100/0x1100 [ 49.634092] [] do_loop_readv_writev.part.18+0xd5/0x280 [ 49.641005] [] do_readv_writev+0x565/0x7a0 [ 49.646865] [] ? vfs_write+0x530/0x530 [ 49.652375] [] ? kasan_unpoison_shadow+0x35/0x50 [ 49.658769] [] ? push_pipe+0x3f4/0x780 [ 49.664323] [] ? iov_iter_get_pages_alloc+0x2bb/0xf10 [ 49.671157] [] vfs_readv+0x84/0xc0 [ 49.676340] [] default_file_splice_read+0x44b/0x7e0 [ 49.683000] [] ? depot_save_stack+0x132/0x460 [ 49.689140] [] ? do_splice_direct+0x270/0x270 [ 49.695273] [] ? save_stack_trace+0x16/0x20 [ 49.701234] [] ? kasan_kmalloc+0xc7/0xe0 [ 49.706934] [] ? __kmalloc+0x11d/0x300 [ 49.712460] [] ? alloc_pipe_info+0x164/0x380 [ 49.718524] [] ? splice_direct_to_actor+0x62c/0x7e0 [ 49.725183] [] ? do_splice_direct+0x1a3/0x270 [ 49.731317] [] ? do_sendfile+0x4f0/0xc60 [ 49.737018] [] ? SyS_sendfile64+0xd1/0x160 [ 49.742887] [] ? entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 49.749979] [] ? __fsnotify_update_child_dentry_flags.part.1+0x300/0x300 [ 49.758469] [] ? fsnotify+0x1100/0x1100 [ 49.764083] [] ? avc_policy_seqno+0x9/0x20 [ 49.769959] [] ? selinux_file_permission+0x82/0x470 [ 49.777565] [] ? security_file_permission+0x8f/0x1f0 [ 49.784397] [] ? do_splice_direct+0x270/0x270 [ 49.790567] [] do_splice_to+0x10c/0x170 [ 49.796187] [] splice_direct_to_actor+0x23f/0x7e0 [ 49.802664] [] ? pipe_to_sendpage+0x330/0x330 [ 49.808816] [] ? do_splice_to+0x170/0x170 [ 49.814596] [] ? security_file_permission+0x8f/0x1f0 [ 49.821337] [] ? rw_verify_area+0xe5/0x2b0 [ 49.827234] [] do_splice_direct+0x1a3/0x270 [ 49.833203] [] ? splice_direct_to_actor+0x7e0/0x7e0 [ 49.839867] [] ? rcu_sync_lockdep_assert+0x73/0xb0 [ 49.846452] [] ? __sb_start_write+0x161/0x300 [ 49.852601] [] do_sendfile+0x4f0/0xc60 [ 49.858148] [] ? do_compat_pwritev64+0x180/0x180 [ 49.864540] [] ? __might_fault+0x114/0x1d0 [ 49.870417] [] SyS_sendfile64+0xd1/0x160 [ 49.876110] [] ? SyS_sendfile+0x160/0x160 [ 49.881910] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 49.888736] [] ? do_syscall_64+0x48/0x490 [ 49.894536] [] ? SyS_sendfile+0x160/0x160 [ 49.900335] [] do_syscall_64+0x1a6/0x490 [ 49.906023] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 49.913375] Dumping ftrace buffer: [ 49.916894] (ftrace buffer empty) [ 49.920580] Kernel Offset: disabled [ 49.924189] Rebooting in 86400 seconds..