[ 34.472408] audit: type=1800 audit(1577080624.103:33): pid=7039 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 34.494664] audit: type=1800 audit(1577080624.103:34): pid=7039 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 38.892079] random: sshd: uninitialized urandom read (32 bytes read) [ 39.295385] audit: type=1400 audit(1577080628.923:35): avc: denied { map } for pid=7211 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 [ 39.345423] random: sshd: uninitialized urandom read (32 bytes read) [ 39.923445] random: sshd: uninitialized urandom read (32 bytes read) [ 40.117777] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.186' (ECDSA) to the list of known hosts. [ 45.634195] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 45.749918] audit: type=1400 audit(1577080635.373:36): avc: denied { map } for pid=7223 comm="syz-executor702" path="/root/syz-executor702617745" 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 [ 45.781613] [ 45.783250] ====================================================== [ 45.789536] WARNING: possible circular locking dependency detected [ 45.795826] 4.14.160-syzkaller #0 Not tainted [ 45.800297] ------------------------------------------------------ [ 45.806627] syz-executor702/7223 is trying to acquire lock: [ 45.812331] ((&strp->work)){+.+.}, at: [] flush_work+0x84/0x730 [ 45.820048] [ 45.820048] but task is already holding lock: [ 45.825991] (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x35d/0x1120 [ 45.833940] [ 45.833940] which lock already depends on the new lock. [ 45.833940] [ 45.842239] [ 45.842239] the existing dependency chain (in reverse order) is: [ 45.849830] [ 45.849830] -> #1 (sk_lock-AF_INET){+.+.}: [ 45.855568] lock_acquire+0x16f/0x430 [ 45.859955] lock_sock_nested+0xbd/0x110 [ 45.864511] strp_sock_lock+0x2e/0x40 [ 45.868911] strp_work+0x43/0x100 [ 45.872896] process_one_work+0x863/0x1600 [ 45.877633] worker_thread+0x5d9/0x1050 [ 45.882106] kthread+0x319/0x430 [ 45.885971] ret_from_fork+0x24/0x30 [ 45.890179] [ 45.890179] -> #0 ((&strp->work)){+.+.}: [ 45.895699] __lock_acquire+0x2cb3/0x4620 [ 45.900346] lock_acquire+0x16f/0x430 [ 45.904640] flush_work+0xae/0x730 [ 45.908677] __cancel_work_timer+0x2f0/0x480 [ 45.913579] cancel_work_sync+0x18/0x20 [ 45.918052] strp_done+0x58/0xe0 [ 45.921915] kcm_ioctl+0x8d9/0x1120 [ 45.926057] sock_do_ioctl+0x64/0xb0 [ 45.930262] sock_ioctl+0x2a6/0x470 [ 45.934380] do_vfs_ioctl+0x7ae/0x1060 [ 45.938788] SyS_ioctl+0x8f/0xc0 [ 45.942655] do_syscall_64+0x1e8/0x640 [ 45.947043] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 45.952726] [ 45.952726] other info that might help us debug this: [ 45.952726] [ 45.960881] Possible unsafe locking scenario: [ 45.960881] [ 45.966911] CPU0 CPU1 [ 45.971550] ---- ---- [ 45.976225] lock(sk_lock-AF_INET); [ 45.979915] lock((&strp->work)); [ 45.985946] lock(sk_lock-AF_INET); [ 45.992154] lock((&strp->work)); [ 45.995667] [ 45.995667] *** DEADLOCK *** [ 45.995667] [ 46.001700] 1 lock held by syz-executor702/7223: [ 46.006468] #0: (sk_lock-AF_INET){+.+.}, at: [] kcm_ioctl+0x35d/0x1120 [ 46.014853] [ 46.014853] stack backtrace: [ 46.019328] CPU: 1 PID: 7223 Comm: syz-executor702 Not tainted 4.14.160-syzkaller #0 [ 46.027184] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.036514] Call Trace: [ 46.039079] dump_stack+0x142/0x197 [ 46.042698] print_circular_bug.isra.0.cold+0x1cc/0x28f [ 46.048040] __lock_acquire+0x2cb3/0x4620 [ 46.052164] ? trace_hardirqs_on+0x10/0x10 [ 46.056379] ? save_trace+0x290/0x290 [ 46.060156] ? debug_object_assert_init+0x163/0x300 [ 46.065161] ? save_trace+0x290/0x290 [ 46.068939] ? __lock_is_held+0xb6/0x140 [ 46.072975] lock_acquire+0x16f/0x430 [ 46.076750] ? flush_work+0x84/0x730 [ 46.080438] ? flush_work+0x5c6/0x730 [ 46.084214] flush_work+0xae/0x730 [ 46.087728] ? flush_work+0x84/0x730 [ 46.091418] ? insert_work+0x320/0x320 [ 46.095281] ? find_held_lock+0x35/0x130 [ 46.099319] ? del_timer+0xbd/0xf0 [ 46.102834] ? mark_held_locks+0xb1/0x100 [ 46.106958] ? __cancel_work_timer+0x166/0x480 [ 46.111528] __cancel_work_timer+0x2f0/0x480 [ 46.115911] ? cancel_delayed_work+0x20/0x20 [ 46.120293] ? mark_held_locks+0xb1/0x100 [ 46.124548] ? __local_bh_enable_ip+0x99/0x1a0 [ 46.129104] cancel_work_sync+0x18/0x20 [ 46.133053] strp_done+0x58/0xe0 [ 46.136407] kcm_ioctl+0x8d9/0x1120 [ 46.140011] ? kcm_done_work+0x20/0x20 [ 46.143882] sock_do_ioctl+0x64/0xb0 [ 46.147578] sock_ioctl+0x2a6/0x470 [ 46.151183] ? dlci_ioctl_set+0x40/0x40 [ 46.155132] do_vfs_ioctl+0x7ae/0x1060 [ 46.158993] ? selinux_file_mprotect+0x5d0/0x5d0 [ 46.163721] ? f_dupfd+0x12f/0x1cf [ 46.167236] ? ioctl_preallocate+0x1c0/0x1c0 [ 46.171619] ? do_fcntl+0x8b/0xe10 [ 46.175135] ? f_getown+0xb0/0xb0 [ 46.178578] ? security_file_ioctl+0x7d/0xb0 [ 46.182978] ? security_file_ioctl+0x89/0xb0 [ 46.187362] SyS_ioctl+0x8f/0xc0 [ 46.190718] ? do_vfs_ioctl+0x1060/0x1060 [ 46.194857] do_syscall_64+0x1e8/0x640 [ 46.198729] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 46.203553] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 46.208721] RIP: 0033:0x440719 [ 46.211888] RSP: 002b:00007ffcb4582d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 46.219586] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440719 [ 46.226836] RDX: 0000000020000080 RSI: 00000000000089e0 RDI: 0000000000000004 [ 46.234088] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 46.241336] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401fa0 [ 46.248581] R13: 0000000000402030 R14: