Warning: Permanently added '10.128.0.42' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 45.429738] kauditd_printk_skb: 2 callbacks suppressed [ 45.429753] audit: type=1400 audit(1569196671.293:36): avc: denied { map } for pid=7512 comm="syz-executor943" path="/root/syz-executor943487959" 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 [ 45.446709] IPVS: ftp: loaded support on port[0] = 21 [ 45.570497] ================================================================== [ 45.577929] BUG: KASAN: use-after-free in __change_pid+0x253/0x2f0 [ 45.584244] Read of size 8 at addr ffff88809b0008c0 by task syz-executor943/7512 [ 45.591756] [ 45.593369] CPU: 0 PID: 7512 Comm: syz-executor943 Not tainted 4.19.75 #0 [ 45.600274] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.609609] Call Trace: [ 45.612194] dump_stack+0x172/0x1f0 [ 45.615805] ? __change_pid+0x253/0x2f0 [ 45.619765] print_address_description.cold+0x7c/0x20d [ 45.625025] ? __change_pid+0x253/0x2f0 [ 45.628981] kasan_report.cold+0x8c/0x2ba [ 45.633123] __asan_report_load8_noabort+0x14/0x20 [ 45.638033] __change_pid+0x253/0x2f0 [ 45.641819] detach_pid+0x20/0x30 [ 45.645255] release_task+0xd65/0x1630 [ 45.649125] ? _raw_spin_unlock_irq+0x28/0x90 [ 45.653605] wait_consider_task+0x2c95/0x3910 [ 45.658087] ? release_task+0x1630/0x1630 [ 45.662216] ? lock_acquire+0x16f/0x3f0 [ 45.666180] ? do_wait+0x3aa/0x9d0 [ 45.669706] ? kasan_check_write+0x14/0x20 [ 45.673966] do_wait+0x439/0x9d0 [ 45.677321] ? wait_consider_task+0x3910/0x3910 [ 45.681980] kernel_wait4+0x171/0x290 [ 45.685769] ? __ia32_sys_waitid+0x140/0x140 [ 45.690165] ? task_stopped_code+0x180/0x180 [ 45.694555] ? find_held_lock+0x35/0x130 [ 45.698603] ? __do_page_fault+0x676/0xe90 [ 45.702823] __do_sys_wait4+0x147/0x160 [ 45.706781] ? kernel_wait4+0x290/0x290 [ 45.710789] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 45.716312] ? up_read+0x1a/0x110 [ 45.719750] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.725269] ? __do_page_fault+0x484/0xe90 [ 45.729489] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.734227] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 45.738967] ? do_syscall_64+0x26/0x620 [ 45.742924] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.748279] ? do_syscall_64+0x26/0x620 [ 45.752239] __x64_sys_wait4+0x97/0xf0 [ 45.756113] do_syscall_64+0xfd/0x620 [ 45.759923] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.765095] RIP: 0033:0x4012aa [ 45.768282] Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 4e 14 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 [ 45.787167] RSP: 002b:00007fff3ef92ed8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d [ 45.794859] RAX: ffffffffffffffda RBX: 0000000000001d59 RCX: 00000000004012aa [ 45.802112] RDX: 0000000040000000 RSI: 00007fff3ef92ee4 RDI: ffffffffffffffff [ 45.809364] RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000555556183880 [ 45.816615] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402260 [ 45.823951] R13: 00000000004022f0 R14: 0000000000000000 R15: 0000000000000000 [ 45.831223] [ 45.832832] Allocated by task 7512: [ 45.836444] save_stack+0x45/0xd0 [ 45.839904] kasan_kmalloc+0xce/0xf0 [ 45.843601] kasan_slab_alloc+0xf/0x20 [ 45.847467] kmem_cache_alloc_node+0x144/0x710 [ 45.852033] copy_process.part.0+0x1ce0/0x7a30 [ 45.856594] _do_fork+0x257/0xfd0 [ 45.860028] __x64_sys_clone+0xbf/0x150 [ 45.863983] do_syscall_64+0xfd/0x620 [ 45.867764] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.872929] [ 45.874536] Freed by task 0: [ 45.877553] save_stack+0x45/0xd0 [ 45.880992] __kasan_slab_free+0x102/0x150 [ 45.885209] kasan_slab_free+0xe/0x10 [ 45.889000] kmem_cache_free+0x86/0x260 [ 45.892960] free_task+0xdd/0x120 [ 45.896394] __put_task_struct+0x20f/0x4c0 [ 45.900870] finish_task_switch+0x52b/0x780 [ 45.905175] __schedule+0x86e/0x1dc0 [ 45.908882] schedule_idle+0x58/0x80 [ 45.912582] do_idle+0x192/0x560 [ 45.915941] cpu_startup_entry+0xc8/0xe0 [ 45.919984] start_secondary+0x3e8/0x5b0 [ 45.924024] secondary_startup_64+0xa4/0xb0 [ 45.928320] [ 45.929929] The buggy address belongs to the object at ffff88809b0001c0 [ 45.929929] which belongs to the cache task_struct of size 6080 [ 45.942654] The buggy address is located 1792 bytes inside of [ 45.942654] 6080-byte region [ffff88809b0001c0, ffff88809b001980) [ 45.954717] The buggy address belongs to the page: [ 45.959630] page:ffffea00026c0000 count:1 mapcount:0 mapping:ffff88812c26d800 index:0x0 compound_mapcount: 0 [ 45.969582] flags: 0x1fffc0000008100(slab|head) [ 45.974235] raw: 01fffc0000008100 ffffea0002688308 ffffea0002694b08 ffff88812c26d800 [ 45.982101] raw: 0000000000000000 ffff88809b0001c0 0000000100000001 0000000000000000 [ 45.989959] page dumped because: kasan: bad access detected [ 45.995644] [ 45.997249] Memory state around the buggy address: [ 46.002159] ffff88809b000780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.009510] ffff88809b000800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.016861] >ffff88809b000880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.024217] ^ [ 46.029665] ffff88809b000900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.037003] ffff88809b000980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 46.044338] ================================================================== [ 46.051686] Disabling lock debugging due to kernel taint [ 46.057112] Kernel panic - not syncing: panic_on_warn set ... [ 46.057112] [ 46.064462] CPU: 0 PID: 7512 Comm: syz-executor943 Tainted: G B 4.19.75 #0 [ 46.072763] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.082105] Call Trace: [ 46.084680] dump_stack+0x172/0x1f0 [ 46.088288] ? __change_pid+0x253/0x2f0 [ 46.092247] panic+0x263/0x507 [ 46.095417] ? __warn_printk+0xf3/0xf3 [ 46.099285] ? lock_downgrade+0x810/0x810 [ 46.103418] ? trace_hardirqs_off+0x62/0x220 [ 46.107809] ? trace_hardirqs_off+0x59/0x220 [ 46.112199] ? __change_pid+0x253/0x2f0 [ 46.116167] kasan_end_report+0x47/0x4f [ 46.120138] kasan_report.cold+0xa9/0x2ba [ 46.124273] __asan_report_load8_noabort+0x14/0x20 [ 46.129189] __change_pid+0x253/0x2f0 [ 46.132996] detach_pid+0x20/0x30 [ 46.136452] release_task+0xd65/0x1630 [ 46.140327] ? _raw_spin_unlock_irq+0x28/0x90 [ 46.144814] wait_consider_task+0x2c95/0x3910 [ 46.149317] ? release_task+0x1630/0x1630 [ 46.153491] ? lock_acquire+0x16f/0x3f0 [ 46.157485] ? do_wait+0x3aa/0x9d0 [ 46.161012] ? kasan_check_write+0x14/0x20 [ 46.165230] do_wait+0x439/0x9d0 [ 46.168607] ? wait_consider_task+0x3910/0x3910 [ 46.173258] kernel_wait4+0x171/0x290 [ 46.177038] ? __ia32_sys_waitid+0x140/0x140 [ 46.181430] ? task_stopped_code+0x180/0x180 [ 46.185833] ? find_held_lock+0x35/0x130 [ 46.189882] ? __do_page_fault+0x676/0xe90 [ 46.194113] __do_sys_wait4+0x147/0x160 [ 46.198107] ? kernel_wait4+0x290/0x290 [ 46.202070] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 46.207592] ? up_read+0x1a/0x110 [ 46.211029] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 46.216550] ? __do_page_fault+0x484/0xe90 [ 46.220768] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 46.225507] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 46.230276] ? do_syscall_64+0x26/0x620 [ 46.234232] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.239575] ? do_syscall_64+0x26/0x620 [ 46.243533] __x64_sys_wait4+0x97/0xf0 [ 46.247433] do_syscall_64+0xfd/0x620 [ 46.251217] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.256387] RIP: 0033:0x4012aa [ 46.259580] Code: c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 8b 05 4e 14 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 [ 46.278461] RSP: 002b:00007fff3ef92ed8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d [ 46.286230] RAX: ffffffffffffffda RBX: 0000000000001d59 RCX: 00000000004012aa [ 46.293498] RDX: 0000000040000000 RSI: 00007fff3ef92ee4 RDI: ffffffffffffffff [ 46.300758] RBP: 00000000006cb018 R08: 0000000000000000 R09: 0000555556183880 [ 46.308024] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000402260 [ 46.315281] R13: 00000000004022f0 R14: 0000000000000000 R15: 0000000000000000 [ 46.323858] Kernel Offset: disabled [ 46.327483] Rebooting in 86400 seconds..