Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [ 39.448458] audit: type=1800 audit(1569269013.352:33): pid=7394 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 39.484615] audit: type=1800 audit(1569269013.352:34): pid=7394 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 Warning: Permanently added '10.128.0.77' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 60.498281] kauditd_printk_skb: 1 callbacks suppressed [ 60.498296] audit: type=1400 audit(1569269034.402:36): avc: denied { map } for pid=7580 comm="syz-executor533" path="/root/syz-executor533099938" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 60.542691] ================================================================== [ 60.550706] BUG: KASAN: use-after-free in wait_consider_task+0x1b51/0x3910 [ 60.559074] Read of size 4 at addr ffff88809921e5ec by task syz-executor533/7580 [ 60.566590] [ 60.568211] CPU: 1 PID: 7580 Comm: syz-executor533 Not tainted 4.19.75 #0 [ 60.575117] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.584509] Call Trace: [ 60.587211] dump_stack+0x172/0x1f0 [ 60.590881] ? wait_consider_task+0x1b51/0x3910 [ 60.595541] print_address_description.cold+0x7c/0x20d [ 60.600814] ? wait_consider_task+0x1b51/0x3910 [ 60.605475] kasan_report.cold+0x8c/0x2ba [ 60.609626] __asan_report_load4_noabort+0x14/0x20 [ 60.614542] wait_consider_task+0x1b51/0x3910 [ 60.619022] ? lockdep_hardirqs_on+0x415/0x5d0 [ 60.623600] ? _raw_spin_unlock_irqrestore+0x6b/0xe0 [ 60.628716] ? add_wait_queue+0x112/0x170 [ 60.632852] ? release_task+0x1630/0x1630 [ 60.636992] ? lock_acquire+0x16f/0x3f0 [ 60.640951] ? do_wait+0x3aa/0x9d0 [ 60.644478] ? kasan_check_write+0x14/0x20 [ 60.648699] do_wait+0x439/0x9d0 [ 60.652054] ? wait_consider_task+0x3910/0x3910 [ 60.656798] kernel_wait4+0x171/0x290 [ 60.660583] ? __ia32_sys_waitid+0x140/0x140 [ 60.665002] ? task_stopped_code+0x180/0x180 [ 60.669422] __do_sys_wait4+0x147/0x160 [ 60.673390] ? kernel_wait4+0x290/0x290 [ 60.677368] ? _copy_to_user+0xc9/0x120 [ 60.681349] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 60.686908] ? put_timespec64+0xda/0x140 [ 60.690965] ? nsecs_to_jiffies+0x30/0x30 [ 60.695107] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.699848] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 60.704589] ? do_syscall_64+0x26/0x620 [ 60.709415] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.714759] ? do_syscall_64+0x26/0x620 [ 60.718733] __x64_sys_wait4+0x97/0xf0 [ 60.722612] do_syscall_64+0xfd/0x620 [ 60.726400] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.731590] RIP: 0033:0x40148a [ 60.734781] Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 6e 22 2d 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d0 ff ff ff f7 [ 60.753678] RSP: 002b:00007fff1265aad8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d [ 60.762077] RAX: ffffffffffffffda RBX: 0000000000001d9d RCX: 000000000040148a [ 60.769344] RDX: 0000000040000001 RSI: 00007fff1265aae4 RDI: ffffffffffffffff [ 60.776714] RBP: 000000000000ec38 R08: 0000000000000000 R09: 00005555564c7880 [ 60.783970] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402440 [ 60.791263] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 60.798562] [ 60.800181] Allocated by task 7580: [ 60.803801] save_stack+0x45/0xd0 [ 60.807242] kasan_kmalloc+0xce/0xf0 [ 60.810951] kasan_slab_alloc+0xf/0x20 [ 60.814832] kmem_cache_alloc_node+0x144/0x710 [ 60.819400] copy_process.part.0+0x1ce0/0x7a30 [ 60.823967] _do_fork+0x257/0xfd0 [ 60.827692] __x64_sys_clone+0xbf/0x150 [ 60.831650] do_syscall_64+0xfd/0x620 [ 60.835446] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.840632] [ 60.842257] Freed by task 0: [ 60.845278] save_stack+0x45/0xd0 [ 60.848720] __kasan_slab_free+0x102/0x150 [ 60.852940] kasan_slab_free+0xe/0x10 [ 60.856724] kmem_cache_free+0x86/0x260 [ 60.860684] free_task+0xdd/0x120 [ 60.864119] __put_task_struct+0x20f/0x4c0 [ 60.868340] finish_task_switch+0x52b/0x780 [ 60.872657] __schedule+0x86e/0x1dc0 [ 60.876355] schedule_idle+0x58/0x80 [ 60.880058] do_idle+0x192/0x560 [ 60.883424] cpu_startup_entry+0xc8/0xe0 [ 60.887477] rest_init+0x219/0x222 [ 60.891012] start_kernel+0x88c/0x8c5 [ 60.894798] x86_64_start_reservations+0x29/0x2b [ 60.899537] x86_64_start_kernel+0x77/0x7b [ 60.903756] secondary_startup_64+0xa4/0xb0 [ 60.908056] [ 60.909685] The buggy address belongs to the object at ffff88809921e180 [ 60.909685] which belongs to the cache task_struct of size 6080 [ 60.922521] The buggy address is located 1132 bytes inside of [ 60.922521] 6080-byte region [ffff88809921e180, ffff88809921f940) [ 60.934990] The buggy address belongs to the page: [ 60.940005] page:ffffea0002648780 count:1 mapcount:0 mapping:ffff88812c26d800 index:0x0 compound_mapcount: 0 [ 60.949963] flags: 0x1fffc0000008100(slab|head) [ 60.954620] raw: 01fffc0000008100 ffffea00020d8b08 ffffea00027a1a08 ffff88812c26d800 [ 60.962487] raw: 0000000000000000 ffff88809921e180 0000000100000001 0000000000000000 [ 60.970351] page dumped because: kasan: bad access detected [ 60.976049] [ 60.977673] Memory state around the buggy address: [ 60.982583] ffff88809921e480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.989935] ffff88809921e500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.997276] >ffff88809921e580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.004626] ^ [ 61.011369] ffff88809921e600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.018730] ffff88809921e680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.026195] ================================================================== [ 61.034259] Disabling lock debugging due to kernel taint [ 61.039849] Kernel panic - not syncing: panic_on_warn set ... [ 61.039849] [ 61.047665] CPU: 1 PID: 7580 Comm: syz-executor533 Tainted: G B 4.19.75 #0 [ 61.055963] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.069601] Call Trace: [ 61.072180] dump_stack+0x172/0x1f0 [ 61.075974] ? wait_consider_task+0x1b51/0x3910 [ 61.080712] panic+0x263/0x507 [ 61.083913] ? __warn_printk+0xf3/0xf3 [ 61.087800] ? retint_kernel+0x2d/0x2d [ 61.091682] ? trace_hardirqs_on+0x5e/0x220 [ 61.096170] ? wait_consider_task+0x1b51/0x3910 [ 61.100826] kasan_end_report+0x47/0x4f [ 61.104785] kasan_report.cold+0xa9/0x2ba [ 61.108920] __asan_report_load4_noabort+0x14/0x20 [ 61.113834] wait_consider_task+0x1b51/0x3910 [ 61.118326] ? lockdep_hardirqs_on+0x415/0x5d0 [ 61.122996] ? _raw_spin_unlock_irqrestore+0x6b/0xe0 [ 61.128084] ? add_wait_queue+0x112/0x170 [ 61.132228] ? release_task+0x1630/0x1630 [ 61.136367] ? lock_acquire+0x16f/0x3f0 [ 61.140331] ? do_wait+0x3aa/0x9d0 [ 61.143864] ? kasan_check_write+0x14/0x20 [ 61.148094] do_wait+0x439/0x9d0 [ 61.151478] ? wait_consider_task+0x3910/0x3910 [ 61.156139] kernel_wait4+0x171/0x290 [ 61.159926] ? __ia32_sys_waitid+0x140/0x140 [ 61.164317] ? task_stopped_code+0x180/0x180 [ 61.168763] __do_sys_wait4+0x147/0x160 [ 61.172718] ? kernel_wait4+0x290/0x290 [ 61.176692] ? _copy_to_user+0xc9/0x120 [ 61.180650] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 61.186169] ? put_timespec64+0xda/0x140 [ 61.190214] ? nsecs_to_jiffies+0x30/0x30 [ 61.194347] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 61.199085] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 61.203823] ? do_syscall_64+0x26/0x620 [ 61.207800] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 61.213165] ? do_syscall_64+0x26/0x620 [ 61.217133] __x64_sys_wait4+0x97/0xf0 [ 61.221006] do_syscall_64+0xfd/0x620 [ 61.224884] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 61.230065] RIP: 0033:0x40148a [ 61.233251] Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 6e 22 2d 00 85 c0 75 36 45 31 d2 48 63 d2 48 63 ff b8 3d 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 d0 ff ff ff f7 [ 61.252244] RSP: 002b:00007fff1265aad8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d [ 61.259951] RAX: ffffffffffffffda RBX: 0000000000001d9d RCX: 000000000040148a [ 61.267220] RDX: 0000000040000001 RSI: 00007fff1265aae4 RDI: ffffffffffffffff [ 61.274473] RBP: 000000000000ec38 R08: 0000000000000000 R09: 00005555564c7880 [ 61.281735] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402440 [ 61.288997] R13: 00000000004024d0 R14: 0000000000000000 R15: 0000000000000000 [ 61.298057] Kernel Offset: disabled [ 61.301745] Rebooting in 86400 seconds..