[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 58.398970][ T26] audit: type=1800 audit(1575258896.051:25): pid=8741 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 58.418893][ T26] audit: type=1800 audit(1575258896.051:26): pid=8741 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 58.472095][ T26] audit: type=1800 audit(1575258896.051:27): pid=8741 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 '10.128.0.228' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 69.091444][ T8895] IPVS: ftp: loaded support on port[0] = 21 [ 69.221902][ T8896] ================================================================== [ 69.230195][ T8896] BUG: KASAN: slab-out-of-bounds in pipe_write+0xe30/0x1000 [ 69.237455][ T8896] Write of size 8 at addr ffff8880905b9728 by task syz-executor088/8896 [ 69.245750][ T8896] [ 69.248063][ T8896] CPU: 1 PID: 8896 Comm: syz-executor088 Not tainted 5.4.0-syzkaller #0 [ 69.256364][ T8896] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.266394][ T8896] Call Trace: [ 69.269665][ T8896] dump_stack+0x197/0x210 [ 69.273993][ T8896] ? pipe_write+0xe30/0x1000 [ 69.278564][ T8896] print_address_description.constprop.0.cold+0xd4/0x30b [ 69.285566][ T8896] ? pipe_write+0xe30/0x1000 [ 69.290132][ T8896] ? pipe_write+0xe30/0x1000 [ 69.294700][ T8896] __kasan_report.cold+0x1b/0x41 [ 69.299614][ T8896] ? pipe_write+0xe30/0x1000 [ 69.304218][ T8896] kasan_report+0x12/0x20 [ 69.308525][ T8896] __asan_report_store8_noabort+0x17/0x20 [ 69.314271][ T8896] pipe_write+0xe30/0x1000 [ 69.318670][ T8896] new_sync_write+0x4d3/0x770 [ 69.323324][ T8896] ? new_sync_read+0x800/0x800 [ 69.328084][ T8896] ? __fget+0x37f/0x550 [ 69.332233][ T8896] ? apparmor_file_permission+0x25/0x30 [ 69.337755][ T8896] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 69.343969][ T8896] ? security_file_permission+0x8f/0x380 [ 69.349578][ T8896] __vfs_write+0xe1/0x110 [ 69.353883][ T8896] vfs_write+0x268/0x5d0 [ 69.358162][ T8896] ksys_write+0x220/0x290 [ 69.362467][ T8896] ? __ia32_sys_read+0xb0/0xb0 [ 69.367207][ T8896] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 69.372642][ T8896] ? do_syscall_64+0x26/0x790 [ 69.377334][ T8896] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.383384][ T8896] ? do_syscall_64+0x26/0x790 [ 69.388036][ T8896] __x64_sys_write+0x73/0xb0 [ 69.392604][ T8896] do_syscall_64+0xfa/0x790 [ 69.397084][ T8896] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.402951][ T8896] RIP: 0033:0x446fd9 [ 69.406827][ T8896] Code: e8 0c 1b 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 3b 0c fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 69.426408][ T8896] RSP: 002b:00007fd99f362ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 69.434794][ T8896] RAX: ffffffffffffffda RBX: 00000000006ddc48 RCX: 0000000000446fd9 [ 69.443016][ T8896] RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000004 [ 69.450970][ T8896] RBP: 00000000006ddc40 R08: 0000000000000000 R09: 0000000000000000 [ 69.458925][ T8896] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc4c [ 69.466872][ T8896] R13: 00007ffc2ecded9f R14: 00007fd99f3639c0 R15: 000000000000002d [ 69.474837][ T8896] [ 69.477142][ T8896] Allocated by task 8898: [ 69.481448][ T8896] save_stack+0x23/0x90 [ 69.485576][ T8896] __kasan_kmalloc.constprop.0+0xcf/0xe0 [ 69.491272][ T8896] kasan_kmalloc+0x9/0x10 [ 69.495586][ T8896] __kmalloc+0x163/0x770 [ 69.499811][ T8896] pipe_fcntl+0x3f7/0x8e0 [ 69.504128][ T8896] do_fcntl+0x255/0x1030 [ 69.508346][ T8896] __x64_sys_fcntl+0x16d/0x1e0 [ 69.513085][ T8896] do_syscall_64+0xfa/0x790 [ 69.517574][ T8896] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.523446][ T8896] [ 69.525758][ T8896] Freed by task 0: [ 69.529457][ T8896] (stack is not available) [ 69.533852][ T8896] [ 69.536165][ T8896] The buggy address belongs to the object at ffff8880905b9700 [ 69.536165][ T8896] which belongs to the cache kmalloc-64 of size 64 [ 69.550021][ T8896] The buggy address is located 40 bytes inside of [ 69.550021][ T8896] 64-byte region [ffff8880905b9700, ffff8880905b9740) [ 69.563091][ T8896] The buggy address belongs to the page: [ 69.568705][ T8896] page:ffffea0002416e40 refcount:1 mapcount:0 mapping:ffff8880aa400380 index:0x0 [ 69.577789][ T8896] raw: 00fffe0000000200 ffffea00025b2488 ffff8880aa401348 ffff8880aa400380 [ 69.586350][ T8896] raw: 0000000000000000 ffff8880905b9000 0000000100000020 0000000000000000 [ 69.594908][ T8896] page dumped because: kasan: bad access detected [ 69.601298][ T8896] [ 69.603604][ T8896] Memory state around the buggy address: [ 69.609210][ T8896] ffff8880905b9600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 69.617254][ T8896] ffff8880905b9680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 69.625290][ T8896] >ffff8880905b9700: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc [ 69.633385][ T8896] ^ [ 69.638736][ T8896] ffff8880905b9780: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc [ 69.646775][ T8896] ffff8880905b9800: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc [ 69.654888][ T8896] ================================================================== [ 69.662926][ T8896] Disabling lock debugging due to kernel taint [ 69.669550][ T8896] Kernel panic - not syncing: panic_on_warn set ... [ 69.676137][ T8896] CPU: 1 PID: 8896 Comm: syz-executor088 Tainted: G B 5.4.0-syzkaller #0 [ 69.685822][ T8896] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 69.695851][ T8896] Call Trace: [ 69.699162][ T8896] dump_stack+0x197/0x210 [ 69.703483][ T8896] panic+0x2e3/0x75c [ 69.707369][ T8896] ? add_taint.cold+0x16/0x16 [ 69.712024][ T8896] ? pipe_write+0xe30/0x1000 [ 69.716587][ T8896] ? preempt_schedule+0x4b/0x60 [ 69.721503][ T8896] ? ___preempt_schedule+0x16/0x18 [ 69.726602][ T8896] ? trace_hardirqs_on+0x5e/0x240 [ 69.731646][ T8896] ? pipe_write+0xe30/0x1000 [ 69.736244][ T8896] end_report+0x47/0x4f [ 69.740384][ T8896] ? pipe_write+0xe30/0x1000 [ 69.744956][ T8896] __kasan_report.cold+0xe/0x41 [ 69.749777][ T8896] ? pipe_write+0xe30/0x1000 [ 69.754338][ T8896] kasan_report+0x12/0x20 [ 69.758652][ T8896] __asan_report_store8_noabort+0x17/0x20 [ 69.764346][ T8896] pipe_write+0xe30/0x1000 [ 69.768738][ T8896] new_sync_write+0x4d3/0x770 [ 69.773386][ T8896] ? new_sync_read+0x800/0x800 [ 69.778226][ T8896] ? __fget+0x37f/0x550 [ 69.782360][ T8896] ? apparmor_file_permission+0x25/0x30 [ 69.787880][ T8896] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 69.794097][ T8896] ? security_file_permission+0x8f/0x380 [ 69.799718][ T8896] __vfs_write+0xe1/0x110 [ 69.804029][ T8896] vfs_write+0x268/0x5d0 [ 69.808250][ T8896] ksys_write+0x220/0x290 [ 69.812561][ T8896] ? __ia32_sys_read+0xb0/0xb0 [ 69.817307][ T8896] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 69.822748][ T8896] ? do_syscall_64+0x26/0x790 [ 69.827411][ T8896] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.833452][ T8896] ? do_syscall_64+0x26/0x790 [ 69.838118][ T8896] __x64_sys_write+0x73/0xb0 [ 69.842683][ T8896] do_syscall_64+0xfa/0x790 [ 69.847162][ T8896] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 69.853028][ T8896] RIP: 0033:0x446fd9 [ 69.856901][ T8896] Code: e8 0c 1b 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 3b 0c fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 69.876508][ T8896] RSP: 002b:00007fd99f362ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 69.884895][ T8896] RAX: ffffffffffffffda RBX: 00000000006ddc48 RCX: 0000000000446fd9 [ 69.892842][ T8896] RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000004 [ 69.900792][ T8896] RBP: 00000000006ddc40 R08: 0000000000000000 R09: 0000000000000000 [ 69.908737][ T8896] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc4c [ 69.916682][ T8896] R13: 00007ffc2ecded9f R14: 00007fd99f3639c0 R15: 000000000000002d [ 69.925991][ T8896] Kernel Offset: disabled [ 69.930315][ T8896] Rebooting in 86400 seconds..