[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 33.972832] random: sshd: uninitialized urandom read (32 bytes read) [ 34.331973] kauditd_printk_skb: 10 callbacks suppressed [ 34.331981] audit: type=1400 audit(1572500426.954:35): avc: denied { map } for pid=6921 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 [ 34.388606] random: sshd: uninitialized urandom read (32 bytes read) [ 34.984741] random: sshd: uninitialized urandom read (32 bytes read) [ 35.180545] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.154' (ECDSA) to the list of known hosts. [ 40.656624] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 40.774312] audit: type=1400 audit(1572500433.394:36): avc: denied { map } for pid=6934 comm="syz-executor803" path="/root/syz-executor803687095" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 40.803962] [ 40.805630] ====================================================== [ 40.812219] WARNING: possible circular locking dependency detected [ 40.818855] 4.14.151 #0 Not tainted [ 40.822587] ------------------------------------------------------ [ 40.829606] kworker/u4:3/269 is trying to acquire lock: [ 40.836120] (sk_lock-AF_INET){+.+.}, at: [] strp_sock_lock+0x2e/0x40 [ 40.844558] [ 40.844558] but task is already holding lock: [ 40.850516] ((&strp->work)){+.+.}, at: [] process_one_work+0x7ab/0x1600 [ 40.859059] [ 40.859059] which lock already depends on the new lock. [ 40.859059] [ 40.867364] [ 40.867364] the existing dependency chain (in reverse order) is: [ 40.874984] [ 40.874984] -> #1 ((&strp->work)){+.+.}: [ 40.880654] lock_acquire+0x16f/0x430 [ 40.885331] flush_work+0xae/0x730 [ 40.889676] __cancel_work_timer+0x2f0/0x480 [ 40.894883] cancel_work_sync+0x18/0x20 [ 40.899370] strp_done+0x58/0xe0 [ 40.903465] kcm_ioctl+0x8d9/0x1120 [ 40.907612] sock_do_ioctl+0x64/0xb0 [ 40.911837] sock_ioctl+0x2a6/0x470 [ 40.916138] do_vfs_ioctl+0x7ae/0x1060 [ 40.920534] SyS_ioctl+0x8f/0xc0 [ 40.924406] do_syscall_64+0x1e8/0x640 [ 40.929025] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 40.934865] [ 40.934865] -> #0 (sk_lock-AF_INET){+.+.}: [ 40.940688] __lock_acquire+0x2cb3/0x4620 [ 40.945492] lock_acquire+0x16f/0x430 [ 40.949801] lock_sock_nested+0xbd/0x110 [ 40.954368] strp_sock_lock+0x2e/0x40 [ 40.958911] strp_work+0x43/0x100 [ 40.962893] process_one_work+0x863/0x1600 [ 40.967635] worker_thread+0x5d9/0x1050 [ 40.972117] kthread+0x319/0x430 [ 40.975993] ret_from_fork+0x24/0x30 [ 40.980208] [ 40.980208] other info that might help us debug this: [ 40.980208] [ 40.988343] Possible unsafe locking scenario: [ 40.988343] [ 40.994386] CPU0 CPU1 [ 40.999084] ---- ---- [ 41.003738] lock((&strp->work)); [ 41.007267] lock(sk_lock-AF_INET); [ 41.013485] lock((&strp->work)); [ 41.019528] lock(sk_lock-AF_INET); [ 41.023370] [ 41.023370] *** DEADLOCK *** [ 41.023370] [ 41.029414] 2 locks held by kworker/u4:3/269: [ 41.034882] #0: ("%s""kstrp"){+.+.}, at: [] process_one_work+0x76e/0x1600 [ 41.043634] #1: ((&strp->work)){+.+.}, at: [] process_one_work+0x7ab/0x1600 [ 41.052469] [ 41.052469] stack backtrace: [ 41.056952] CPU: 0 PID: 269 Comm: kworker/u4:3 Not tainted 4.14.151 #0 [ 41.063865] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.073218] Workqueue: kstrp strp_work [ 41.077219] Call Trace: [ 41.079804] dump_stack+0x138/0x197 [ 41.083549] print_circular_bug.isra.0.cold+0x1cc/0x28f [ 41.089101] __lock_acquire+0x2cb3/0x4620 [ 41.093372] ? _raw_spin_unlock_irq+0x5e/0x90 [ 41.097870] ? trace_hardirqs_on+0x10/0x10 [ 41.102101] ? save_trace+0x290/0x290 [ 41.106038] ? lock_sock_nested+0x9e/0x110 [ 41.110353] ? lock_sock_nested+0x9e/0x110 [ 41.115250] lock_acquire+0x16f/0x430 [ 41.119876] ? strp_sock_lock+0x2e/0x40 [ 41.124286] lock