[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 24.257846] random: sshd: uninitialized urandom read (32 bytes read) [ 24.762493] audit: type=1400 audit(1570267090.136:6): avc: denied { map } for pid=1774 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 [ 24.861576] random: sshd: uninitialized urandom read (32 bytes read) [ 25.385357] random: sshd: uninitialized urandom read (32 bytes read) [ 25.541406] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.207' (ECDSA) to the list of known hosts. [ 30.964980] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 31.071892] audit: type=1400 audit(1570267096.446:7): avc: denied { map } for pid=1786 comm="syz-executor586" path="/root/syz-executor586962917" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 31.075208] kasan: CONFIG_KASAN_INLINE enabled [ 31.103119] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 31.111085] general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 31.117817] Modules linked in: [ 31.120997] CPU: 0 PID: 1786 Comm: syz-executor586 Not tainted 4.14.146+ #0 [ 31.128071] task: (ptrval) task.stack: (ptrval) [ 31.134110] RIP: 0010:__blockdev_direct_IO+0x1dcf/0xe24e [ 31.139534] RSP: 0018:ffff8881ccac7330 EFLAGS: 00010202 [ 31.144897] RAX: dffffc0000000000 RBX: ffffea000733f21c RCX: ffffffff95638603 [ 31.152288] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000020 [ 31.160078] RBP: ffff8881ccac7668 R08: 0000000000000000 R09: fffff94000e67e44 [ 31.167338] R10: fffff94000e67e43 R11: ffffea000733f21f R12: ffffea000733f200 [ 31.174632] R13: ffffea000733f200 R14: 0000000000000000 R15: ffff8881c01f8000 [ 31.181892] FS: 0000555555a05880(0000) GS:ffff8881d7400000(0000) knlGS:0000000000000000 [ 31.190093] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 31.195950] CR2: 0000563160ea5100 CR3: 00000001cd7de002 CR4: 00000000001606b0 [ 31.203208] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 31.210463] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 31.217707] Call Trace: [ 31.220285] ? sb_init_dio_done_wq+0x90/0x90 [ 31.224675] ? __bfs+0x25/0x540 [ 31.227942] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 31.233542] ? lock_downgrade+0x5d0/0x5d0 [ 31.237668] ext4_direct_IO+0xa4f/0x2820 [ 31.241716] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 31.247337] ? ext4_da_write_begin+0x10c0/0x10c0 [ 31.252077] ? current_time+0x16/0xb0 [ 31.255910] ? mark_held_locks+0xa6/0xf0 [ 31.259952] ? timespec_trunc+0xc9/0x140 [ 31.263995] ? put_itimerspec64+0x1c0/0x1c0 [ 31.268299] ? trace_hardirqs_on_caller+0x37b/0x540 [ 31.273296] ? current_kernel_time64+0xb6/0x100 [ 31.277951] ? current_time+0x89/0xb0 [ 31.281734] ? filemap_check_errors+0x8b/0xb0 [ 31.286207] generic_file_direct_write+0x1e4/0x430 [ 31.291114] __generic_file_write_iter+0x209/0x550 [ 31.296017] ? generic_write_checks+0x252/0x410 [ 31.300660] ext4_file_write_iter+0x58f/0xdb0 [ 31.305131] ? ext4_llseek+0x7f0/0x7f0 [ 31.308993] ? __lock_acquire+0x26eb/0x4320 [ 31.313295] ? lock_acquire+0x170/0x360 [ 31.317244] do_iter_readv_writev+0x379/0x580 [ 31.321718] ? clone_verify_area+0x1e0/0x1e0 [ 31.326103] ? avc_policy_seqno+0x5/0x10 [ 31.330148] ? security_file_permission+0x88/0x1e0 [ 31.335063] do_iter_write+0x152/0x550 [ 31.338931] vfs_iter_write+0x70/0xa0 [ 31.342705] iter_file_splice_write+0x560/0xa50 [ 31.347360] ? vmsplice_to_user+0x1e0/0x1e0 [ 31.351684] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 31.357121] ? rcu_read_lock_sched_held+0x10a/0x130 [ 31.362119] ? vmsplice_to_user+0x1e0/0x1e0 [ 31.366424] SyS_splice+0xcd6/0x1270 [ 31.370116] ? filp_open+0x60/0x60 [ 31.373631] ? SyS_recv+0x40/0x40 [ 31.377060] ? compat_SyS_vmsplice+0x150/0x150 [ 31.381616] ? do_syscall_64+0x43/0x520 [ 31.385564] ? compat_SyS_vmsplice+0x150/0x150 [ 31.390129] do_syscall_64+0x19b/0x520 [ 31.393994] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 31.399159] RIP: 0033:0x440309 [ 31.402333] RSP: 002b:00007ffc7af657e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 31.410019] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 [ 31.417268] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 31.424521] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 31.431766] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 [ 31.439106] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 31.446361] Code: ec 96 e8 85 69 e9 ff 0f 0b e8 0e bc cd ff 48 8b 84 24 e8 00 00 00 48 8d 78 20 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 37 a0 00 00 48 8b 84 24 e8 00 00 00 4c 8b 60 [ 31.465429] RIP: __blockdev_direct_IO+0x1dcf/0xe24e RSP: ffff8881ccac7330 [ 31.472425] ---[ end trace aa9a06c1ae523fe8 ]--- [ 31.477184] Kernel panic - not syncing: Fatal exception [ 31.483169] Kernel Offset: 0x14000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 31.494071] Rebooting in 86400 seconds..