[ 33.251144] audit: type=1800 audit(1576214108.541:34): pid=7023 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 37.706244] random: sshd: uninitialized urandom read (32 bytes read) [ 38.093212] audit: type=1400 audit(1576214113.411:35): avc: denied { map } for pid=7195 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 [ 38.130204] random: sshd: uninitialized urandom read (32 bytes read) [ 38.675998] random: sshd: uninitialized urandom read (32 bytes read) [ 145.854019] audit: type=1400 audit(1576214221.171:36): avc: denied { map } for pid=7203 comm="sh" path="/bin/dash" dev="sda1" ino=1473 scontext=system_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 [ 478.067017] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.104' (ECDSA) to the list of known hosts. [ 483.764483] 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 [ 483.891186] audit: type=1400 audit(1576214559.211:37): avc: denied { map } for pid=7210 comm="syz-executor426" path="/root/syz-executor426794500" dev="sda1" ino=1426 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 [ 484.130521] ================================================================== [ 484.130693] BUG: KASAN: use-after-free in n_tty_receive_buf_common+0x1feb/0x2410 [ 484.130700] Read of size 1 at addr ffff88809f0eec01 by task syz-executor426/7262 [ 484.130702] [ 484.130711] CPU: 0 PID: 7262 Comm: syz-executor426 Not tainted 4.14.158-syzkaller #0 [ 484.130715] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 484.130735] Call Trace: [ 484.130784] dump_stack+0x142/0x197 [ 484.180314] ? n_tty_receive_buf_common+0x1feb/0x2410 [ 484.180382] print_address_description.cold+0x7c/0x1dc [ 484.180392] ? n_tty_receive_buf_common+0x1feb/0x2410 [ 484.180399] kasan_report.cold+0xa9/0x2af [ 484.180409] __asan_report_load1_noabort+0x14/0x20 [ 484.180417] n_tty_receive_buf_common+0x1feb/0x2410 [ 484.180440] n_tty_receive_buf2+0x34/0x40 [ 484.215275] ? n_tty_receive_buf_common+0x2410/0x2410 [ 484.215281] tty_ldisc_receive_buf+0xa5/0x1a0 [ 484.215321] paste_selection+0x1e6/0x3f2 [ 484.215384] ? find_held_lock+0x35/0x130 [ 484.215394] ? set_selection+0xe30/0xe30 [ 484.215404] ? lock_downgrade+0x740/0x740 [ 484.215441] ? wake_up_q+0xf0/0xf0 [ 484.215454] tioclinux+0x10e/0x400 [ 484.215462] vt_ioctl+0x180c/0x2170 [ 484.215492] ? avc_has_extended_perms+0x8ec/0xe40 [ 484.215502] ? complete_change_console+0x360/0x360 [ 484.261985] ? avc_ss_reset+0x110/0x110 [ 484.261998] ? do_raw_spin_unlock+0x16b/0x260 [ 484.262006] ? tty_jobctrl_ioctl+0x44/0xc10 [ 484.262073] ? _raw_spin_unlock+0x2d/0x50 [ 484.262080] ? complete_change_console+0x360/0x360 [ 484.262091] tty_ioctl+0x841/0x1320 [ 484.262100] ? tty_vhangup+0x30/0x30 [ 484.262115] ? __might_sleep+0x93/0xb0 [ 484.262122] ? save_trace+0x290/0x290 [ 484.262134] ? tty_vhangup+0x30/0x30 [ 484.303344] do_vfs_ioctl+0x7ae/0x1060 [ 484.303359] ? selinux_file_mprotect+0x5d0/0x5d0 [ 484.303368] ? ioctl_preallocate+0x1c0/0x1c0 [ 484.303379] ? lock_downgrade+0x740/0x740 [ 484.303417] ? security_file_ioctl+0x7d/0xb0 [ 484.303425] ? security_file_ioctl+0x89/0xb0 [ 484.329334] SyS_ioctl+0x8f/0xc0 [ 484.329342] ? do_vfs_ioctl+0x1060/0x1060 [ 484.329352] do_syscall_64+0x1e8/0x640 [ 484.329358] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 484.329370] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 484.329379] RIP: 0033:0x441339 [ 484.329383] RSP: 002b:00007ffd1c9af498 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 484.329392] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339 [ 484.329396] RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 [ 484.329400] RBP: 00000000000762d2 R08: 000000000000000d R09: 00000000004002c8 [ 484.329405] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004020b0 [ 484.329409] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000 [ 484.329422] [ 484.329483] Allocated by task 7259: [ 484.329491] save_stack_trace+0x16/0x20 [ 484.329498] save_stack+0x45/0xd0 [ 484.329504] kasan_kmalloc+0xce/0xf0 [ 484.329509] __kmalloc+0x15d/0x7a0 [ 484.329516] set_selection+0x79a/0xe30 [ 484.329522] tioclinux+0xf7/0x400 [ 484.329527] vt_ioctl+0x180c/0x2170 [ 484.329534] tty_ioctl+0x841/0x1320 [ 484.329540] do_vfs_ioctl+0x7ae/0x1060 [ 484.329546] SyS_ioctl+0x8f/0xc0 [ 484.329554] do_syscall_64+0x1e8/0x640 [ 484.443933] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 484.443936] [ 484.443939] Freed by task 7261: [ 484.443947] save_stack_trace+0x16/0x20 [ 484.443953] save_stack+0x45/0xd0 [ 484.443958] kasan_slab_free+0x75/0xc0 [ 484.443963] kfree+0xcc/0x270 [ 484.443969] set_selection+0x7b7/0xe30 [ 484.443974] tioclinux+0xf7/0x400 [ 484.443979] vt_ioctl+0x180c/0x2170 [ 484.443986] tty_ioctl+0x841/0x1320 [ 484.443994] do_vfs_ioctl+0x7ae/0x1060 [ 484.444000] SyS_ioctl+0x8f/0xc0 [ 484.444007] do_syscall_64+0x1e8/0x640 [ 484.444014] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 484.444016] [ 484.444021] The buggy address belongs to the object at ffff88809f0eec00 [ 484.444021] which belongs to the cache kmalloc-256 of size 256 [ 484.444027] The buggy address is located 1 bytes inside of [ 484.444027] 256-byte region [ffff88809f0eec00, ffff88809f0eed00) [ 484.444030] The buggy address belongs to the page: executing program [ 484.444036] page:ffffea00027c3b80 count:1 mapcount:0 mapping:ffff88809f0ee0c0 index:0x0 [ 484.444044] flags: 0xfffe0000000100(slab) [ 484.444053] raw: 00fffe0000000100 ffff88809f0ee0c0 0000000000000000 000000010000000c [ 484.444060] raw: ffffea000268d8e0 ffff8880aa801648 ffff8880aa8007c0 0000000000000000 [ 484.444063] page dumped because: kasan: bad access detected [ 484.444068] [ 484.566219] Memory state around the buggy address: [ 484.566227] ffff88809f0eeb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 484.566233] ffff88809f0eeb80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 484.566237] >ffff88809f0eec00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 484.566240] ^ [ 484.566245] ffff88809f0eec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 484.566249] ffff88809f0eed00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 484.566251] ================================================================== [ 484.566254] Disabling lock debugging due to kernel taint [ 484.567002] Kernel panic - not syncing: panic_on_warn set ... [ 484.567002] [ 484.632181] CPU: 0 PID: 7262 Comm: syz-executor426 Tainted: G B 4.14.158-syzkaller #0 [ 484.632185] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 484.632187] Call Trace: [ 484.632203] dump_stack+0x142/0x197 [ 484.632216] ? n_tty_receive_buf_common+0x1feb/0x2410 [ 484.662060] panic+0x1f9/0x42d [ 484.662068] ? add_taint.cold+0x16/0x16 [ 484.662077] ? ___preempt_schedule+0x16/0x18 [ 484.662087] kasan_end_report+0x47/0x4f [ 484.662094] kasan_report.cold+0x130/0x2af [ 484.662102] __asan_report_load1_noabort+0x14/0x20 [ 484.662111] n_tty_receive_buf_common+0x1feb/0x2410 [ 484.662126] n_tty_receive_buf2+0x34/0x40 [ 484.662133] ? n_tty_receive_buf_common+0x2410/0x2410 [ 484.662138] tty_ldisc_receive_buf+0xa5/0x1a0 [ 484.662147] paste_selection+0x1e6/0x3f2 [ 484.662153] ? find_held_lock+0x35/0x130 [ 484.662160] ? set_selection+0xe30/0xe30 [ 484.662168] ? lock_downgrade+0x740/0x740 [ 484.662175] ? wake_up_q+0xf0/0xf0 [ 484.662183] tioclinux+0x10e/0x400 [ 484.662189] vt_ioctl+0x180c/0x2170 [ 484.662196] ? avc_has_extended_perms+0x8ec/0xe40 [ 484.662204] ? complete_change_console+0x360/0x360 [ 484.662210] ? avc_ss_reset+0x110/0x110 [ 484.662218] ? do_raw_spin_unlock+0x16b/0x260 [ 484.662224] ? tty_jobctrl_ioctl+0x44/0xc10 [ 484.662232] ? _raw_spin_unlock+0x2d/0x50 [ 484.662237] ? complete_change_console+0x360/0x360 [ 484.662243] tty_ioctl+0x841/0x1320 [ 484.662250] ? tty_vhangup+0x30/0x30 [ 484.662263] ? __might_sleep+0x93/0xb0 [ 484.777283] ? save_trace+0x290/0x290 [ 484.777297] ? tty_vhangup+0x30/0x30 [ 484.777305] do_vfs_ioctl+0x7ae/0x1060 [ 484.777315] ? selinux_file_mprotect+0x5d0/0x5d0 [ 484.777321] ? ioctl_preallocate+0x1c0/0x1c0 [ 484.777327] ? lock_downgrade+0x740/0x740 [ 484.777336] ? security_file_ioctl+0x7d/0xb0 [ 484.777342] ? security_file_ioctl+0x89/0xb0 [ 484.777349] SyS_ioctl+0x8f/0xc0 [ 484.777355] ? do_vfs_ioctl+0x1060/0x1060 [ 484.777364] do_syscall_64+0x1e8/0x640 [ 484.777371] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 484.777382] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 484.777388] RIP: 0033:0x441339 [ 484.777395] RSP: 002b:00007ffd1c9af498 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 484.777403] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441339 [ 484.777407] RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 [ 484.777410] RBP: 00000000000762d2 R08: 000000000000000d R09: 00000000004002c8 [ 484.777414] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004020b0 [ 484.777417] R13: 0000000000402140 R14: 0000000000000000 R15: 0000000000000000 [ 484.782693] Kernel Offset: disabled [ 484.884302] Rebooting in 86400 seconds..