[ 40.637263] audit: type=1800 audit(1556913386.237:31): pid=7465 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 46.429446] kauditd_printk_skb: 3 callbacks suppressed [ 46.429459] audit: type=1400 audit(1556913392.067:35): avc: denied { map } for pid=7641 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 Warning: Permanently added '10.128.1.13' (ECDSA) to the list of known hosts. [ 58.773786] audit: type=1400 audit(1556913404.417:36): avc: denied { map } for pid=7653 comm="syz-executor483" path="/root/syz-executor483480724" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 58.796236] IPVS: ftp: loaded support on port[0] = 21 [ 58.817320] IPVS: ftp: loaded support on port[0] = 21 [ 58.823844] IPVS: ftp: loaded support on port[0] = 21 [ 58.825383] IPVS: ftp: loaded support on port[0] = 21 [ 58.834800] IPVS: ftp: loaded support on port[0] = 21 [ 58.842023] IPVS: ftp: loaded support on port[0] = 21 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 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 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 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 executing program executing program executing program [ 59.652134] ================================================================== [ 59.659822] BUG: KASAN: null-ptr-deref in kthread_stop+0x78/0x6d0 [ 59.666589] Write of size 4 at addr 0000000000000020 by task syz-executor483/8037 [ 59.674497] [ 59.676141] CPU: 1 PID: 8037 Comm: syz-executor483 Not tainted 4.19.38 #6 [ 59.683151] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.692612] Call Trace: [ 59.695240] dump_stack+0x172/0x1f0 [ 59.699026] ? kthread_stop+0x78/0x6d0 [ 59.702920] kasan_report.cold+0x254/0x2fa [ 59.707240] check_memory_region+0x123/0x190 [ 59.711980] kasan_check_write+0x14/0x20 [ 59.716069] kthread_stop+0x78/0x6d0 [ 59.719805] vivid_stop_generating_vid_cap+0x1e0/0x6e2 [ 59.725223] ? _vb2_fop_release+0x3f/0x2a0 [ 59.729662] vid_cap_stop_streaming+0x8a/0xe0 [ 59.734297] ? vid_cap_buf_queue+0x280/0x280 [ 59.738716] __vb2_queue_cancel+0xb4/0x970 [ 59.742958] ? lock_downgrade+0x810/0x810 [ 59.747102] ? v4l2_fh_is_singular+0xff/0x160 [ 59.751593] vb2_core_streamoff+0x60/0x140 [ 59.755833] __vb2_cleanup_fileio+0x78/0x170 [ 59.760548] vb2_core_queue_release+0x20/0x80 [ 59.765061] _vb2_fop_release+0x1cf/0x2a0 [ 59.769233] vb2_fop_release+0x75/0xc0 [ 59.773118] vivid_fop_release+0x18e/0x430 [ 59.777368] ? vivid_remove+0x460/0x460 [ 59.781451] ? dev_debug_store+0x110/0x110 [ 59.785930] v4l2_release+0xfb/0x1a0 [ 59.789646] __fput+0x2df/0x8b0 [ 59.792918] ____fput+0x16/0x20 [ 59.796188] task_work_run+0x14a/0x1c0 [ 59.800180] exit_to_usermode_loop+0x273/0x2c0 [ 59.804769] do_syscall_64+0x52d/0x610 [ 59.808798] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 59.813988] RIP: 0033:0x44b599 [ 59.817179] Code: e8 dc e6 ff ff 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 9b c9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 59.836714] RSP: 002b:00007fcc7b5adce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000124 [ 59.844415] RAX: 0000000000000004 RBX: 00000000006ddc58 RCX: 000000000044b599 [ 59.851890] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 [ 59.859430] RBP: 00000000006ddc50 R08: 0000000000000000 R09: 0000000000000000 [ 59.866702] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc5c [ 59.874213] R13: 00007fff97d6464f R14: 00007fcc7b5ae9c0 R15: 0000000000000000 [ 59.881534] ================================================================== [ 59.888891] Disabling lock debugging due to kernel taint [ 59.894875] Kernel panic - not syncing: panic_on_warn set ... [ 59.894875] executing program [ 59.902525] CPU: 1 PID: 8037 Comm: syz-executor483 Tainted: G B 4.19.38 #6 [ 59.911226] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.920925] Call Trace: [ 59.923519] dump_stack+0x172/0x1f0 [ 59.927150] ? kthread_stop+0x78/0x6d0 [ 59.931032] panic+0x263/0x51d [ 59.934222] ? __warn_printk+0xf3/0xf3 [ 59.938092] ? kthread_stop+0x78/0x6d0 [ 59.942013] ? preempt_schedule+0x4b/0x60 [ 59.946280] ? ___preempt_schedule+0x16/0x18 [ 59.950683] ? trace_hardirqs_on+0x5e/0x230 [ 59.954991] ? kthread_stop+0x78/0x6d0 [ 59.958879] kasan_end_report+0x47/0x4f [ 59.962844] kasan_report.cold+0xcb/0x2fa [ 59.966987] check_memory_region+0x123/0x190 [ 59.971388] kasan_check_write+0x14/0x20 [ 59.975558] kthread_stop+0x78/0x6d0 [ 59.979293] vivid_stop_generating_vid_cap+0x1e0/0x6e2 [ 59.984575] ? _vb2_fop_release+0x3f/0x2a0 [ 59.988804] vid_cap_stop_streaming+0x8a/0xe0 [ 59.993286] ? vid_cap_buf_queue+0x280/0x280 [ 59.997823] __vb2_queue_cancel+0xb4/0x970 [ 60.002063] ? lock_downgrade+0x810/0x810 [ 60.006218] ? v4l2_fh_is_singular+0xff/0x160 [ 60.010711] vb2_core_streamoff+0x60/0x140 [ 60.014938] __vb2_cleanup_fileio+0x78/0x170 [ 60.019343] vb2_core_queue_release+0x20/0x80 [ 60.023838] _vb2_fop_release+0x1cf/0x2a0 [ 60.027985] vb2_fop_release+0x75/0xc0 [ 60.031872] vivid_fop_release+0x18e/0x430 [ 60.036112] ? vivid_remove+0x460/0x460 [ 60.040079] ? dev_debug_store+0x110/0x110 [ 60.044413] v4l2_release+0xfb/0x1a0 [ 60.048118] __fput+0x2df/0x8b0 [ 60.051388] ____fput+0x16/0x20 [ 60.054658] task_work_run+0x14a/0x1c0 [ 60.058605] exit_to_usermode_loop+0x273/0x2c0 [ 60.063191] do_syscall_64+0x52d/0x610 [ 60.067091] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 60.072274] RIP: 0033:0x44b599 [ 60.075720] Code: e8 dc e6 ff ff 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 9b c9 fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 60.094770] RSP: 002b:00007fcc7b5adce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000124 [ 60.102481] RAX: 0000000000000004 RBX: 00000000006ddc58 RCX: 000000000044b599 [ 60.109744] RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000003 [ 60.117014] RBP: 00000000006ddc50 R08: 0000000000000000 R09: 0000000000000000 [ 60.124389] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc5c [ 60.131651] R13: 00007fff97d6464f R14: 00007fcc7b5ae9c0 R15: 0000000000000000 [ 60.140951] Kernel Offset: disabled [ 60.144591] Rebooting in 86400 seconds..