[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 87.109484][ T27] audit: type=1800 audit(1581582538.925:25): pid=9522 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 87.144678][ T27] audit: type=1800 audit(1581582538.925:26): pid=9522 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 87.184350][ T27] audit: type=1800 audit(1581582538.925:27): pid=9522 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.2' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 97.411827][ T9673] ================================================================== [ 97.411882][ T9673] BUG: KASAN: null-ptr-deref in do_con_trol+0x3b9/0x61b0 [ 97.411895][ T9673] Read of size 4294967294 at addr 0000000000000012 by task syz-executor841/9673 [ 97.411899][ T9673] [ 97.411914][ T9673] CPU: 0 PID: 9673 Comm: syz-executor841 Not tainted 5.6.0-rc1-syzkaller #0 [ 97.411933][ T9673] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.411937][ T9673] Call Trace: [ 97.411955][ T9673] dump_stack+0x197/0x210 [ 97.411970][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.411984][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.412003][ T9673] __kasan_report.cold+0x5/0x32 [ 97.412024][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.412047][ T9673] kasan_report+0x12/0x20 [ 97.412067][ T9673] check_memory_region+0x134/0x1a0 [ 97.412085][ T9673] memcpy+0x24/0x50 [ 97.412102][ T9673] do_con_trol+0x3b9/0x61b0 [ 97.412127][ T9673] ? reset_palette+0x190/0x190 [ 97.412147][ T9673] ? __kasan_check_read+0x11/0x20 [ 97.412172][ T9673] ? __atomic_notifier_call_chain+0xf8/0x1a0 [ 97.412202][ T9673] do_con_write.part.0+0xfd9/0x1ef0 [ 97.412246][ T9673] ? do_con_trol+0x61b0/0x61b0 [ 97.412260][ T9673] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.412272][ T9673] ? add_wait_queue+0x112/0x170 [ 97.412285][ T9673] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.412310][ T9673] ? trace_hardirqs_on+0x67/0x240 [ 97.412341][ T9673] con_write+0x46/0xd0 [ 97.412362][ T9673] n_tty_write+0x40e/0x1080 [ 97.412407][ T9673] ? n_tty_read+0x1bf0/0x1bf0 [ 97.412426][ T9673] ? prepare_to_wait_exclusive+0x320/0x320 [ 97.412450][ T9673] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 97.412464][ T9673] ? _copy_from_user+0x12c/0x1a0 [ 97.412483][ T9673] tty_write+0x496/0x7f0 [ 97.412502][ T9673] ? n_tty_read+0x1bf0/0x1bf0 [ 97.412527][ T9673] __vfs_write+0x8a/0x110 [ 97.412540][ T9673] ? put_tty_driver+0x20/0x20 [ 97.412563][ T9673] vfs_write+0x268/0x5d0 [ 97.412592][ T9673] ksys_write+0x14f/0x290 [ 97.412615][ T9673] ? __ia32_sys_read+0xb0/0xb0 [ 97.412636][ T9673] ? do_syscall_64+0x26/0x790 [ 97.412651][ T9673] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.412667][ T9673] ? do_syscall_64+0x26/0x790 [ 97.412695][ T9673] __x64_sys_write+0x73/0xb0 [ 97.412717][ T9673] do_syscall_64+0xfa/0x790 [ 97.412740][ T9673] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.412752][ T9673] RIP: 0033:0x4404f9 [ 97.412767][ T9673] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 14 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 97.412775][ T9673] RSP: 002b:00007ffefa71b898 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 97.412790][ T9673] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404f9 [ 97.412799][ T9673] RDX: 0000000000000078 RSI: 0000000020000140 RDI: 0000000000000004 [ 97.412808][ T9673] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 97.412816][ T9673] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401de0 [ 97.412825][ T9673] R13: 0000000000401e70 R14: 0000000000000000 R15: 0000000000000000 [ 97.412860][ T9673] ================================================================== [ 97.412865][ T9673] Disabling lock debugging due to kernel taint [ 97.418928][ T9673] Kernel panic - not syncing: panic_on_warn set ... [ 97.418945][ T9673] CPU: 0 PID: 9673 Comm: syz-executor841 Tainted: G B 5.6.0-rc1-syzkaller #0 [ 97.418952][ T9673] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 97.418955][ T9673] Call Trace: [ 97.418974][ T9673] dump_stack+0x197/0x210 [ 97.418993][ T9673] panic+0x2e3/0x75c [ 97.419007][ T9673] ? add_taint.cold+0x16/0x16 [ 97.419023][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.419039][ T9673] ? preempt_schedule+0x4b/0x60 [ 97.419055][ T9673] ? ___preempt_schedule+0x16/0x18 [ 97.419073][ T9673] ? trace_hardirqs_on+0x5e/0x240 [ 97.419087][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.419103][ T9673] end_report+0x47/0x4f [ 97.419115][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.419130][ T9673] __kasan_report.cold+0xe/0x32 [ 97.419144][ T9673] ? do_con_trol+0x3b9/0x61b0 [ 97.419161][ T9673] kasan_report+0x12/0x20 [ 97.419178][ T9673] check_memory_region+0x134/0x1a0 [ 97.419193][ T9673] memcpy+0x24/0x50 [ 97.419206][ T9673] do_con_trol+0x3b9/0x61b0 [ 97.419223][ T9673] ? reset_palette+0x190/0x190 [ 97.419239][ T9673] ? __kasan_check_read+0x11/0x20 [ 97.419259][ T9673] ? __atomic_notifier_call_chain+0xf8/0x1a0 [ 97.419278][ T9673] do_con_write.part.0+0xfd9/0x1ef0 [ 97.419302][ T9673] ? do_con_trol+0x61b0/0x61b0 [ 97.419320][ T9673] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.419335][ T9673] ? add_wait_queue+0x112/0x170 [ 97.419350][ T9673] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 97.419368][ T9673] ? trace_hardirqs_on+0x67/0x240 [ 97.419391][ T9673] con_write+0x46/0xd0 [ 97.419415][ T9673] n_tty_write+0x40e/0x1080 [ 97.419440][ T9673] ? n_tty_read+0x1bf0/0x1bf0 [ 97.419456][ T9673] ? prepare_to_wait_exclusive+0x320/0x320 [ 97.419475][ T9673] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 97.419491][ T9673] ? _copy_from_user+0x12c/0x1a0 [ 97.419506][ T9673] tty_write+0x496/0x7f0 [ 97.419521][ T9673] ? n_tty_read+0x1bf0/0x1bf0 [ 97.419540][ T9673] __vfs_write+0x8a/0x110 [ 97.419553][ T9673] ? put_tty_driver+0x20/0x20 [ 97.419570][ T9673] vfs_write+0x268/0x5d0 [ 97.419588][ T9673] ksys_write+0x14f/0x290 [ 97.419605][ T9673] ? __ia32_sys_read+0xb0/0xb0 [ 97.419622][ T9673] ? do_syscall_64+0x26/0x790 [ 97.419637][ T9673] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.419652][ T9673] ? do_syscall_64+0x26/0x790 [ 97.419670][ T9673] __x64_sys_write+0x73/0xb0 [ 97.419687][ T9673] do_syscall_64+0xfa/0x790 [ 97.419703][ T9673] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 97.419716][ T9673] RIP: 0033:0x4404f9 [ 97.419732][ T9673] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b 14 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 97.419742][ T9673] RSP: 002b:00007ffefa71b898 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 97.419763][ T9673] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404f9 [ 97.419774][ T9673] RDX: 0000000000000078 RSI: 0000000020000140 RDI: 0000000000000004 [ 97.419785][ T9673] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 97.419796][ T9673] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401de0 [ 97.419807][ T9673] R13: 0000000000401e70 R14: 0000000000000000 R15: 0000000000000000 [ 97.421466][ T9673] Kernel Offset: disabled [ 98.061044][ T9673] Rebooting in 86400 seconds..