[....] Starting OpenBSD Secure Shell server: sshd[ 12.542840] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 16.922892] random: sshd: uninitialized urandom read (32 bytes read) [ 17.450376] audit: type=1400 audit(1571483361.783:6): avc: denied { map } for pid=1765 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 [ 17.521884] random: sshd: uninitialized urandom read (32 bytes read) [ 18.077395] random: sshd: uninitialized urandom read (32 bytes read) [ 18.233819] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.67' (ECDSA) to the list of known hosts. [ 23.724646] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 23.825054] audit: type=1400 audit(1571483368.153:7): avc: denied { map } for pid=1783 comm="syz-executor356" path="/root/syz-executor356769185" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 23.829100] kasan: CONFIG_KASAN_INLINE enabled [ 23.857480] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 23.865312] general protection fault: 0000 [#1] PREEMPT SMP KASAN NOPTI [ 23.872064] Modules linked in: [ 23.875243] CPU: 0 PID: 1783 Comm: syz-executor356 Not tainted 4.14.150+ #0 [ 23.882440] task: (ptrval) task.stack: (ptrval) [ 23.888501] RIP: 0010:__blockdev_direct_IO+0x1dcf/0xe24e [ 23.893951] RSP: 0018:ffff8881c4e7f330 EFLAGS: 00010202 [ 23.899293] RAX: dffffc0000000000 RBX: ffffea00073f061c RCX: ffffffffaca394e3 [ 23.906546] RDX: 0000000000000004 RSI: 0000000000000004 RDI: 0000000000000020 [ 23.913811] RBP: ffff8881c4e7f668 R08: 0000000000000000 R09: fffff94000e7e0c4 [ 23.921073] R10: fffff94000e7e0c3 R11: ffffea00073f061f R12: ffffea00073f0600 [ 23.928321] R13: ffffea00073f0600 R14: 0000000000000000 R15: ffff8881d0594000 [ 23.935569] FS: 0000000000766880(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 [ 23.943866] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.949736] CR2: 0000000020011000 CR3: 00000001d0680006 CR4: 00000000001606b0 [ 23.957953] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 23.965219] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 23.972465] Call Trace: [ 23.975062] ? sb_init_dio_done_wq+0x90/0x90 [ 23.979461] ? __bfs+0x25/0x540 [ 23.982725] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 23.988336] ? lock_downgrade+0x630/0x630 [ 23.992475] ext4_direct_IO+0xa4f/0x2820 [ 23.996516] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 24.002128] ? ext4_da_write_begin+0x10c0/0x10c0 [ 24.007061] ? current_time+0x16/0xb0 [ 24.010840] ? mark_held_locks+0xa6/0xf0 [ 24.014969] ? timespec_trunc+0xc9/0x140 [ 24.019445] ? put_itimerspec64+0x1c0/0x1c0 [ 24.023745] ? trace_hardirqs_on_caller+0x37b/0x540 [ 24.028819] ? current_kernel_time64+0xb6/0x100 [ 24.033485] ? current_time+0x89/0xb0 [ 24.037270] ? filemap_check_errors+0x8b/0xb0 [ 24.041745] generic_file_direct_write+0x1e4/0x430 [ 24.046680] __generic_file_write_iter+0x209/0x550 [ 24.051602] ? generic_write_checks+0x252/0x410 [ 24.056267] ext4_file_write_iter+0x58f/0xdb0 [ 24.060832] ? ext4_llseek+0x7f0/0x7f0 [ 24.064706] ? __lock_acquire+0x26eb/0x4320 [ 24.069004] ? lock_acquire+0x170/0x360 [ 24.072969] do_iter_readv_writev+0x379/0x580 [ 24.077463] ? clone_verify_area+0x1e0/0x1e0 [ 24.081860] ? avc_policy_seqno+0x5/0x10 [ 24.085898] ? security_file_permission+0x88/0x1e0 [ 24.090901] do_iter_write+0x152/0x550 [ 24.094774] vfs_iter_write+0x70/0xa0 [ 24.098561] iter_file_splice_write+0x560/0xa50 [ 24.103220] ? vmsplice_to_user+0x1e0/0x1e0 [ 24.107628] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 24.113069] ? rcu_read_lock_sched_held+0x10a/0x130 [ 24.118071] ? vmsplice_to_user+0x1e0/0x1e0 [ 24.122370] SyS_splice+0xcd6/0x1270 [ 24.126065] ? filp_open+0x60/0x60 [ 24.129585] ? SyS_recv+0x40/0x40 [ 24.133194] ? compat_SyS_vmsplice+0x150/0x150 [ 24.137762] ? do_syscall_64+0x43/0x520 [ 24.141715] ? compat_SyS_vmsplice+0x150/0x150 [ 24.146279] do_syscall_64+0x19b/0x520 [ 24.150149] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 24.155337] RIP: 0033:0x440309 [ 24.158503] RSP: 002b:00007ffc42f0fe18 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 24.166761] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440309 [ 24.174182] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 24.181443] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 24.188706] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b90 [ 24.195958] R13: 0000000000401c20 R14: 0000000000000000 R15: 0000000000000000 [ 24.203319] Code: 2c ae e8 c5 64 e9 ff 0f 0b e8 1e b5 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 [ 24.222585] RIP: __blockdev_direct_IO+0x1dcf/0xe24e RSP: ffff8881c4e7f330 [ 24.230088] ---[ end trace ee9028529258537c ]--- [ 24.234852] Kernel panic - not syncing: Fatal exception [ 24.240824] Kernel Offset: 0x2b400000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) [ 24.251765] Rebooting in 86400 seconds..