[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 53.889502][ T26] audit: type=1800 audit(1569262852.495:25): pid=8529 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 53.934147][ T26] audit: type=1800 audit(1569262852.495:26): pid=8529 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 53.976731][ T26] audit: type=1800 audit(1569262852.495:27): pid=8529 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 '10.128.0.50' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 65.640314][ T8682] 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. [ 65.667768][ T2577] BUG: assuming atomic context at net/kcm/kcmsock.c:382 [ 65.675121][ T2577] in_atomic(): 0, irqs_disabled(): 0, pid: 2577, name: kworker/u4:4 [ 65.684287][ T2577] 3 locks held by kworker/u4:4/2577: [ 65.689740][ T2577] #0: ffff8882166c43e8 ((wq_completion)kstrp){+.+.}, at: process_one_work+0x88b/0x1740 [ 65.699768][ T2577] #1: ffff8880a1ce7dc0 ((work_completion)(&strp->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 65.710960][ T2577] #2: ffff88808d1c0cd0 (sk_lock-AF_INET){+.+.}, at: strp_sock_lock+0x2e/0x40 [ 65.719949][ T2577] CPU: 1 PID: 2577 Comm: kworker/u4:4 Not tainted 5.3.0+ #0 [ 65.727233][ T2577] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.737532][ T2577] Workqueue: kstrp strp_work [ 65.742205][ T2577] Call Trace: [ 65.745492][ T2577] dump_stack+0x172/0x1f0 [ 65.749822][ T2577] __cant_sleep.cold+0xa4/0xbc [ 65.754581][ T2577] kcm_parse_func_strparser+0x54/0x200 [ 65.760030][ T2577] ? memset+0x32/0x40 [ 65.764002][ T2577] __strp_recv+0x5dc/0x1b20 [ 65.768536][ T2577] strp_recv+0xcf/0x10b [ 65.772685][ T2577] tcp_read_sock+0x285/0xa00 [ 65.777261][ T2577] ? strp_process+0xf0/0xf0 [ 65.781788][ T2577] ? compat_tcp_getsockopt+0x80/0x80 [ 65.787062][ T2577] ? mark_held_locks+0xa4/0xf0 [ 65.791822][ T2577] ? __local_bh_enable_ip+0x15a/0x270 [ 65.797180][ T2577] ? lock_sock_nested+0xe2/0x120 [ 65.802107][ T2577] ? compat_tcp_getsockopt+0x80/0x80 [ 65.807512][ T2577] strp_read_sock+0x14d/0x200 [ 65.812178][ T2577] ? strp_stop+0x40/0x40 [ 65.816408][ T2577] ? lock_sock_nested+0xe2/0x120 [ 65.821458][ T2577] strp_work+0xe3/0x130 [ 65.825600][ T2577] process_one_work+0x9af/0x1740 [ 65.830720][ T2577] ? __schedule+0x776/0x17d0 [ 65.835554][ T2577] ? pwq_dec_nr_in_flight+0x320/0x320 [ 6