[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 31.632864] random: sshd: uninitialized urandom read (32 bytes read) [ 31.910665] kauditd_printk_skb: 9 callbacks suppressed [ 31.910673] audit: type=1400 audit(1571583882.052:35): avc: denied { map } for pid=6896 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 [ 31.958444] random: sshd: uninitialized urandom read (32 bytes read) [ 32.486217] random: sshd: uninitialized urandom read (32 bytes read) [ 32.662875] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.208' (ECDSA) to the list of known hosts. [ 38.105465] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 38.220701] audit: type=1400 audit(1571583888.362:36): avc: denied { map } for pid=6909 comm="syz-executor216" path="/root/syz-executor216206009" 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 [ 38.225112] kasan: CONFIG_KASAN_INLINE enabled [ 38.250693] audit: type=1800 audit(1571583888.362:37): pid=6909 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 op="collect_data" cause="failed(directio)" comm="syz-executor216" name="bus" dev="sda1" ino=16485 res=0 [ 38.253462] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 38.282211] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 38.288429] Modules linked in: [ 38.291616] CPU: 0 PID: 6909 Comm: syz-executor216 Not tainted 4.14.150 #0 [ 38.298628] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 38.307957] task: ffff88807e526180 task.stack: ffff88807c7b8000 [ 38.313997] RIP: 0010:do_blockdev_direct_IO+0x1c75/0x7fd0 [ 38.319507] RSP: 0018:ffff88807c7bf4c0 EFLAGS: 00010202 [ 38.324942] RAX: dffffc0000000000 RBX: ffffea000244741c RCX: 000000000000000c [ 38.332187] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000020 [ 38.339432] RBP: ffff88807c7bf7d8 R08: ffffed101385af61 R09: ffff88809c2d7a80 [ 38.346693] R10: ffffed101385af60 R11: ffff88809c2d7b07 R12: ffffea0002447400 [ 38.353948] R13: ffffea0002447400 R14: 0000000000000000 R15: ffff8880a4fd5a40 [ 38.361202] FS: 00000000014a5880(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000 [ 38.369401] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 38.375356] CR2: 000055c4b6e5b1a0 CR3: 00000000a0972000 CR4: 00000000001406f0 [ 38.382606] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 38.389850] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 38.397101] Call Trace: [ 38.399713] ? __ext4_get_inode_loc+0x392/0xf30 [ 38.404373] ? sb_init_dio_done_wq+0x80/0x80 [ 38.408759] ? __lock_acquire+0x2521/0x4620 [ 38.413060] ? save_trace+0x290/0x290 [ 38.416837] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 38.422444] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 38.428059] __blockdev_direct_IO+0xa1/0xca [ 38.432354] ? write_end_fn+0xa0/0xa0 [ 38.436135] ext4_direct_IO+0x70d/0x1890 [ 38.440169] ? ext4_dio_get_block_unwritten_sync+0xd0/0xd0 [ 38.445768] generic_file_direct_write+0x1e7/0x430 [ 38.450672] __generic_file_write_iter+0x2bc/0x5b0 [ 38.455578] ext4_file_write_iter+0x2ac/0xe90 [ 38.460075] ? ext4_file_mmap+0x2c0/0x2c0 [ 38.464200] ? __might_sleep+0x93/0xb0 [ 38.468065] do_iter_readv_writev+0x418/0x670 [ 38.472539] ? vfs_dedupe_file_range+0x8f0/0x8f0 [ 38.477336] ? rw_verify_area+0xea/0x2b0 [ 38.481390] do_iter_write+0x154/0x540 [ 38.485305] ? rcu_lockdep_current_cpu_online+0xf2/0x140 [ 38.490779] ? __kmalloc+0x376/0x7a0 [ 38.494475] vfs_iter_write+0x77/0xb0 [ 38.498254] iter_file_splice_write+0x572/0xad0 [ 38.502903] ? default_file_splice_read+0x7b0/0x7b0 [ 38.507900] ? __lock_is_held+0xb6/0x140 [ 38.511980] ? rcu_sync_lockdep_assert+0x6d/0xb0 [ 38.516724] ? __sb_start_write+0x153/0x2f0 [ 38.521052] ? default_file_splice_read+0x7b0/0x7b0 [ 38.526046] SyS_splice+0xd92/0x1430 [ 38.529740] ? do_sys_open+0x221/0x430 [ 38.533620] ? compat_SyS_vmsplice+0x250/0x250 [ 38.538183] ? do_syscall_64+0x53/0x640 [ 38.542148] ? compat_SyS_vmsplice+0x250/0x250 [ 38.546708] do_syscall_64+0x1e8/0x640 [ 38.550584] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 38.555491] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 38.560653] RIP: 0033:0x4402f9 [ 38.563818] RSP: 002b:00007ffd2c16f6e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 [ 38.571509] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004402f9 [ 38.578756] RDX: 0000000000000007 RSI: 0000000000000000 RDI: 0000000000000004 [ 38.586003] RBP: 00000000006ca018 R08: 00000000ffffffff R09: 0000000000000000 [ 38.593249] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401b80 [ 38.600508] R13: 0000000000401c10 R14: 0000000000000000 R15: 0000000000000000 [ 38.607759] Code: 32 93 d8 ff e9 4a 1d 00 00 e8 b8 50 c1 ff 48 8b 84 24 f0 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 3d 54 00 00 48 8b 84 24 f0 00 00 00 4c 8b 60 [ 38.626831] RIP: do_blockdev_direct_IO+0x1c75/0x7fd0 RSP: ffff88807c7bf4c0 [ 38.634153] ---[ end trace 67e18a01de617bd0 ]--- [ 38.638897] Kernel panic - not syncing: Fatal exception [ 38.645647] Kernel Offset: disabled [ 38.649267] Rebooting in 86400 seconds..