[....] Starting OpenBSD Secure Shell server: sshd[ 12.785586] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 42.204365] random: sshd: uninitialized urandom read (32 bytes read) [ 42.735337] audit: type=1400 audit(1570844973.304:6): avc: denied { map } for pid=1775 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 42.767676] random: sshd: uninitialized urandom read (32 bytes read) [ 43.313736] random: sshd: uninitialized urandom read (32 bytes read) [ 43.478066] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.1.4' (ECDSA) to the list of known hosts. [ 49.142965] 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 [ 49.238074] audit: type=1400 audit(1570844979.804:7): avc: denied { map } for pid=1793 comm="syz-executor074" path="/root/syz-executor074679295" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 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 [ 49.520939] ================================================================== [ 49.528396] BUG: KASAN: stack-out-of-bounds in unwind_next_frame+0x169f/0x1810 [ 49.535868] Read of size 8 at addr ffff8881cfc4f860 by task syz-executor074/1864 [ 49.543490] [ 49.545121] CPU: 1 PID: 1864 Comm: syz-executor074 Not tainted 4.14.148+ #0 [ 49.552233] Call Trace: [ 49.554828] dump_stack+0xca/0x134 [ 49.558410] ? unwind_next_frame+0x169f/0x1810 [ 49.563001] ? unwind_next_frame+0x169f/0x1810 [ 49.567590] print_address_description+0x60/0x226 [ 49.572436] ? unwind_next_frame+0x169f/0x1810 [ 49.577027] ? unwind_next_frame+0x169f/0x1810 [ 49.581641] __kasan_report.cold+0x1a/0x41 [ 49.585895] ? unwind_next_frame+0x169f/0x1810 [ 49.590484] unwind_next_frame+0x169f/0x1810 [ 49.594902] ? retint_kernel+0x2d/0x2d [ 49.598799] ? perf_callchain_user+0x4a7/0xf80 [ 49.603391] ? deref_stack_reg+0xe0/0xe0 [ 49.607463] ? perf_callchain_user+0x2d1/0xf80 [ 49.612048] ? retint_kernel+0x2d/0x2d [ 49.615942] perf_callchain_kernel+0x3a0/0x540 [ 49.620529] ? perf_callchain_kernel+0x540/0x540 [ 49.625378] ? arch_perf_update_userpage+0x330/0x330 [ 49.630518] ? futex_wait_setup+0x132/0x330 [ 49.634860] get_perf_callchain+0x2f5/0x770 [ 49.639195] ? put_callchain_buffers+0x60/0x60 [ 49.643786] ? perf_event_alloc.part.0+0x13e1/0x1ff0 [ 49.648922] ? perf_callchain+0x150/0x190 [ 49.653096] perf_callchain+0x147/0x190 [ 49.657079] perf_prepare_sample+0x6a8/0x1360 [ 49.661583] ? perf_output_sample+0x1700/0x1700 [ 49.666264] ? perf_prepare_sample+0x1360/0x1360 [ 49.671034] ? perf_event_output_forward+0x12f/0x220 [ 49.676167] ? lock_downgrade+0x630/0x630 [ 49.680328] perf_event_output_forward+0xdc/0x220 [ 49.685181] ? perf_prepare_sample+0x1360/0x1360 [ 49.689954] ? __perf_event_overflow+0x1cc/0x340 [ 49.694718] ? check_preemption_disabled+0x35/0x1f0 [ 49.699744] __perf_event_overflow+0x12d/0x340 [ 49.704339] perf_swevent_overflow+0x7a/0xf0 [ 49.708755] perf_swevent_event+0x112/0x270 [ 49.713086] perf_tp_event+0x633/0x7f0 [ 49.716983] ? perf_swevent_put_recursion_context+0xa0/0xa0 [ 49.722715] ? trace_hardirqs_on+0x10/0x10 [ 49.727048] ? __lock_acquire+0x5d7/0x4320 [ 49.731299] ? perf_trace_run_bpf_submit+0x113/0x170 [ 49.736415] ? check_preemption_disabled+0x35/0x1f0 [ 49.741477] perf_trace_run_bpf_submit+0x113/0x170 [ 49.746434] perf_trace_lock_acquire+0x341/0x4e0 [ 49.751206] ? HARDIRQ_verbose+0x10/0x10 [ 49.755533] ? retint_kernel+0x2d/0x2d [ 49.759433] ? get_futex_key+0x4c1/0xf90 [ 49.763507] lock_acquire+0x279/0x360 [ 49.767430] ? futex_wait_setup+0x132/0x330 [ 49.771796] _raw_spin_lock+0x2a/0x40 [ 49.775631] ? futex_wait_setup+0x132/0x330 [ 49.779969] futex_wait_setup+0x132/0x330 [ 49.784132] ? futex_wake+0x440/0x440 [ 49.787945] futex_wait+0x1ad/0x570 [ 49.791584] ? futex_wait_setup+0x330/0x330 [ 49.796086] ? wake_up_q+0xea/0x150 [ 49.799722] ? drop_futex_key_refs.isra.0+0x17/0xb0 [ 49.804834] ? futex_wake+0x15b/0x440 [ 49.808652] ? HARDIRQ_verbose+0x10/0x10 [ 49.812718] ? SyS_perf_event_open+0x1a4d/0x2560 [ 49.817491] do_futex+0x13f/0x1980 [ 49.821042] ? lock_downgrade+0x630/0x630 [ 49.825195] ? lock_acquire+0x12b/0x360 [ 49.829176] ? check_preemption_disabled+0x35/0x1f0 [ 49.834202] ? exit_robust_list+0x240/0x240 [ 49.838533] ? __mutex_unlock_slowpath+0xff/0x690 [ 49.843391] ? get_unused_fd_flags+0xc0/0xc0 [ 49.847836] ? SyS_perf_event_open+0x19c3/0x2560 [ 49.852604] ? wait_for_completion_io+0x10/0x10 [ 49.857280] ? mark_held_locks+0xa6/0xf0 [ 49.861361] ? do_raw_spin_lock+0xb4/0x1d0 [ 49.865694] ? _raw_spin_unlock_irqrestore+0x54/0x70 [ 49.870809] ? SyS_perf_event_open+0x633/0x2560 [ 49.875511] SyS_futex+0x1c5/0x2c3 [ 49.879064] ? do_futex+0x1980/0x1980 [ 49.883134] ? do_syscall_64+0x43/0x520 [ 49.887118] ? do_futex+0x1980/0x1980 [ 49.890922] do_syscall_64+0x19b/0x520 [ 49.894819] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 49.900009] RIP: 0033:0x4467e9 [ 49.903198] RSP: 002b:00007fd22e803db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 49.910915] RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 00000000004467e9 [ 49.918369] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28 [ 49.925654] RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 [ 49.932934] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c [ 49.940220] R13: 00007ffdda6f9b5f R14: 00007fd22e8049c0 R15: 0000000000000000 [ 49.947509] [ 49.949135] The buggy address belongs to the page: [ 49.954151] page:ffffea00073f13c0 count:0 mapcount:0 mapping: (null) index:0x0 [ 49.962446] flags: 0x4000000000000000() [ 49.966427] raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff [ 49.974315] raw: 0000000000000000 ffffea00073f13e0 0000000000000000 0000000000000000 [ 49.982368] page dumped because: kasan: bad access detected [ 49.988077] [ 49.989700] Memory state around the buggy address: [ 49.994634] ffff8881cfc4f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 50.002147] ffff8881cfc4f780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 50.009862] >ffff8881cfc4f800: 00 00 00 f1 f1 f1 f1 f1 f1 04 f2 00 f3 f3 f3 00 [ 50.017226] ^ [ 50.023726] ffff8881cfc4f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 50.031093] ffff8881cfc4f900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 50.038458] ================================================================== [ 50.046117] Disabling lock debugging due to kernel taint [ 50.051573] Kernel panic - not syncing: panic_on_warn set ... [ 50.051573] [ 50.059174] CPU: 1 PID: 1864 Comm: syz-executor074 Tainted: G B 4.14.148+ #0 [ 50.067497] Call Trace: [ 50.070102] dump_stack+0xca/0x134 [ 50.073657] panic+0x1ea/0x3d3 [ 50.076866] ? add_taint.cold+0x16/0x16 [ 50.080968] ? lock_downgrade+0x630/0x630 [ 50.085128] ? unwind_next_frame+0x169f/0x1810 [ 50.089810] end_report+0x43/0x49 [ 50.093286] ? unwind_next_frame+0x169f/0x1810 [ 50.098125] __kasan_report.cold+0xd/0x41 [ 50.102501] ? unwind_next_frame+0x169f/0x1810 [ 50.107091] unwind_next_frame+0x169f/0x1810 [ 50.111535] ? retint_kernel+0x2d/0x2d [ 50.115433] ? perf_callchain_user+0x4a7/0xf80 [ 50.120021] ? deref_stack_reg+0xe0/0xe0 [ 50.124184] ? perf_callchain_user+0x2d1/0xf80 [ 50.128773] ? retint_kernel+0x2d/0x2d [ 50.132669] perf_callchain_kernel+0x3a0/0x540 [ 50.137261] ? perf_callchain_kernel+0x540/0x540 [ 50.142032] ? arch_perf_update_userpage+0x330/0x330 [ 50.147145] ? futex_wait_setup+0x132/0x330 [ 50.151477] get_perf_callchain+0x2f5/0x770 [ 50.155815] ? put_callchain_buffers+0x60/0x60 [ 50.160436] ? perf_event_alloc.part.0+0x13e1/0x1ff0 [ 50.165555] ? perf_callchain+0x150/0x190 [ 50.169715] perf_callchain+0x147/0x190 [ 50.173712] perf_prepare_sample+0x6a8/0x1360 [ 50.178228] ? perf_output_sample+0x1700/0x1700 [ 50.182908] ? perf_prepare_sample+0x1360/0x1360 [ 50.187673] ? perf_event_output_forward+0x12f/0x220 [ 50.192877] ? lock_downgrade+0x630/0x630 [ 50.197147] perf_event_output_forward+0xdc/0x220 [ 50.202002] ? perf_prepare_sample+0x1360/0x1360 [ 50.206775] ? __perf_event_overflow+0x1cc/0x340 [ 50.211543] ? check_preemption_disabled+0x35/0x1f0 [ 50.216572] __perf_event_overflow+0x12d/0x340 [ 50.221180] perf_swevent_overflow+0x7a/0xf0 [ 50.225603] perf_swevent_event+0x112/0x270 [ 50.229955] perf_tp_event+0x633/0x7f0 [ 50.233862] ? perf_swevent_put_recursion_context+0xa0/0xa0 [ 50.239634] ? trace_hardirqs_on+0x10/0x10 [ 50.243881] ? __lock_acquire+0x5d7/0x4320 [ 50.248132] ? perf_trace_run_bpf_submit+0x113/0x170 [ 50.253242] ? check_preemption_disabled+0x35/0x1f0 [ 50.258275] perf_trace_run_bpf_submit+0x113/0x170 [ 50.263215] perf_trace_lock_acquire+0x341/0x4e0 [ 50.268249] ? HARDIRQ_verbose+0x10/0x10 [ 50.272320] ? retint_kernel+0x2d/0x2d [ 50.276220] ? get_futex_key+0x4c1/0xf90 [ 50.280291] lock_acquire+0x279/0x360 [ 50.284103] ? futex_wait_setup+0x132/0x330 [ 50.288436] _raw_spin_lock+0x2a/0x40 [ 50.292245] ? futex_wait_setup+0x132/0x330 [ 50.296576] futex_wait_setup+0x132/0x330 [ 50.300741] ? futex_wake+0x440/0x440 [ 50.304672] futex_wait+0x1ad/0x570 [ 50.308313] ? futex_wait_setup+0x330/0x330 [ 50.312650] ? wake_up_q+0xea/0x150 [ 50.316293] ? drop_futex_key_refs.isra.0+0x17/0xb0 [ 50.321323] ? futex_wake+0x15b/0x440 [ 50.325151] ? HARDIRQ_verbose+0x10/0x10 [ 50.330231] ? SyS_perf_event_open+0x1a4d/0x2560 [ 50.335001] do_futex+0x13f/0x1980 [ 50.338572] ? lock_downgrade+0x630/0x630 [ 50.342728] ? lock_acquire+0x12b/0x360 [ 50.346849] ? check_preemption_disabled+0x35/0x1f0 [ 50.351878] ? exit_robust_list+0x240/0x240 [ 50.356208] ? __mutex_unlock_slowpath+0xff/0x690 [ 50.361408] ? get_unused_fd_flags+0xc0/0xc0 [ 50.365829] ? SyS_perf_event_open+0x19c3/0x2560 [ 50.370604] ? wait_for_completion_io+0x10/0x10 [ 50.375297] ? mark_held_locks+0xa6/0xf0 [ 50.379454] ? do_raw_spin_lock+0xb4/0x1d0 [ 50.383699] ? _raw_spin_unlock_irqrestore+0x54/0x70 [ 50.388938] ? SyS_perf_event_open+0x633/0x2560 [ 50.393624] SyS_futex+0x1c5/0x2c3 [ 50.397181] ? do_futex+0x1980/0x1980 [ 50.400998] ? do_syscall_64+0x43/0x520 [ 50.404980] ? do_futex+0x1980/0x1980 [ 50.408789] do_syscall_64+0x19b/0x520 [ 50.412755] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 50.417965] RIP: 0033:0x4467e9 [ 50.421157] RSP: 002b:00007fd22e803db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 50.428869] RAX: ffffffffffffffda RBX: 00000000006dbc28 RCX: 00000000004467e9 [ 50.436144] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc28 [ 50.443416] RBP: 00000000006dbc20 R08: 0000000000000000 R09: 0000000000000000 [ 50.450693] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc2c [ 50.457968] R13: 00007ffdda6f9b5f R14: 00007fd22e8049c0 R15: 0000000000000000 [ 50.466119] Kernel Offset: 0x29c00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 50.477630] Rebooting in 86400 seconds..