[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 55.083847][ T26] audit: type=1800 audit(1569282823.660:25): pid=8592 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 55.105808][ T26] audit: type=1800 audit(1569282823.660:26): pid=8592 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 55.144573][ T26] audit: type=1800 audit(1569282823.670:27): pid=8592 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 '10.128.0.30' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 63.322382][ T8746] 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. [ 63.348102][ T34] BUG: assuming atomic context at net/kcm/kcmsock.c:382 [ 63.355294][ T34] in_atomic(): 0, irqs_disabled(): 0, pid: 34, name: kworker/u4:2 [ 63.363143][ T34] 3 locks held by kworker/u4:2/34: [ 63.368244][ T34] #0: ffff88809cb2f3e8 ((wq_completion)kstrp){+.+.}, at: process_one_work+0x88b/0x1740 [ 63.378038][ T34] #1: ffff8880a9aefdc0 ((work_completion)(&strp->work)){+.+.}, at: process_one_work+0x8c1/0x1740 [ 63.388663][ T34] #2: ffff888093ca6cd0 (sk_lock-AF_INET){+.+.}, at: strp_sock_lock+0x2e/0x40 [ 63.397580][ T34] CPU: 1 PID: 34 Comm: kworker/u4:2 Not tainted 5.3.0+ #0 [ 63.404686][ T34] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.414729][ T34] Workqueue: kstrp strp_work [ 63.419295][ T34] Call Trace: [ 63.422603][ T34] dump_stack+0x172/0x1f0 [ 63.426917][ T34] __cant_sleep.cold+0xa4/0xbc [ 63.431691][ T34] kcm_parse_func_strparser+0x54/0x200 [ 63.437129][ T34] ? memset+0x32/0x40 [ 63.441092][ T34] __strp_recv+0x5dc/0x1b20 [ 63.445576][ T34] strp_recv+0xcf/0x10b [ 63.449745][ T34] tcp_read_sock+0x285/0xa00 [ 63.454321][ T34] ? strp_process+0xf0/0xf0 [ 63.458803][ T34] ? compat_tcp_getsockopt+0x80/0x80 [ 63.464066][ T34] ? mark_held_locks+0xa4/0xf0 [ 63.468817][ T34] ? __local_bh_enable_ip+0x15a/0x270 [ 63.474173][ T34] ? lock_sock_nested+0xe2/0x120 [ 63.479087][ T34] ? compat_tcp_getsockopt+0x80/0x80 [ 63.484348][ T34] strp_read_sock+0x14d/0x200 [ 63.489010][ T34] ? strp_stop+0x40/0x40 [ 63.493236][ T34] ? lock_sock_nested+0xe2/0x120 [ 63.498173][ T34] strp_work+0xe3/0x130 [ 63.502317][ T34] process_one_work+0x9af/0x1740 [ 63.507237][ T34] ? __schedule+0x776/0x17d0 [ 63.511807][ T34] ? pwq_dec_nr_in_flight+0x320/0x320 [ 63.517160][ T34] ? lock_acquire+0x190/0x410 [ 63.521822][ T