[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 53.378549][ T25] audit: type=1800 audit(1569263480.564:25): pid=8452 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 53.422110][ T25] audit: type=1800 audit(1569263480.574:26): pid=8452 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 53.446300][ T25] audit: type=1800 audit(1569263480.574:27): pid=8452 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 '10.128.0.7' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 61.688902][ T8608] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. [ 61.715976][ T7] BUG: assuming atomic context at net/kcm/kcmsock.c:382 [ 61.723375][ T7] in_atomic(): 0, irqs_disabled(): 0, pid: 7, name: kworker/u4:0 [ 61.731596][ T7] 3 locks held by kworker/u4:0/7: [ 61.736613][ T7] #0: ffff888216726128 ((wq_completion)kstrp){+.+.}, at: process_one_work+0x88b/0x1740 [ 61.746423][ T7] #1: ffff8880a989fdc0 ((work_completion)(&strp->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 61.757060][ T7] #2: ffff888098998d10 (sk_lock-AF_INET){+.+.}, at: strp_sock_lock+0x2e/0x40 [ 61.766003][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.3.0+ #0 [ 61.774067][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.784140][ T7] Workqueue: kstrp strp_work [ 61.788715][ T7] Call Trace: [ 61.792055][ T7] dump_stack+0x172/0x1f0 [ 61.796381][ T7] __cant_sleep.cold+0xa4/0xbc [ 61.801258][ T7] kcm_parse_func_strparser+0x54/0x200 [ 61.806754][ T7] ? memset+0x32/0x40 [ 61.810719][ T7] __strp_recv+0x5dc/0x1b20 [ 61.815248][ T7] strp_recv+0xcf/0x10b [ 61.819407][ T7] tcp_read_sock+0x285/0xa00 [ 61.824089][ T7] ? strp_process+0xf0/0xf0 [ 61.828581][ T7] ? compat_tcp_getsockopt+0x80/0x80 [ 61.833862][ T7] ? mark_held_locks+0xa4/0xf0 [ 61.838611][ T7] ? __local_bh_enable_ip+0x15a/0x270 [ 61.843959][ T7] ? lock_sock_nested+0xe2/0x120 [ 61.848884][ T7] ? compat_tcp_getsockopt+0x80/0x80 [ 61.854164][ T7] strp_read_sock+0x14d/0x200 [ 61.858855][ T7] ? strp_stop+0x40/0x40 [ 61.863088][ T7] ? lock_sock_nested+0xe2/0x120 [ 61.868012][ T7] strp_work+0xe3/0x130 [ 61.872150][ T7] process_one_work+0x9af/0x1740 [ 61.877065][ T7] ? __schedule+0x776/0x17d0 [ 61.881637][ T7] ? pwq_dec_nr_in_flight+0x320/0x320 [ 61.886994][ T7] ? lock_acq