[....] Starting OpenBSD Secure Shell server: sshd[ 8.115339] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 16.518001] random: sshd: uninitialized urandom read (32 bytes read) [ 16.724766] random: sshd: uninitialized urandom read (32 bytes read) [ 17.183123] random: sshd: uninitialized urandom read (32 bytes read) [ 17.463422] random: crng init done [ 17.467055] random: 1 urandom warning(s) missed due to ratelimiting Warning: Permanently added '10.128.0.157' (ECDSA) to the list of known hosts. executing program [ 23.073939] kasan: CONFIG_KASAN_INLINE enabled [ 23.078532] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 23.086974] general protection fault: 0000 [#1] PREEMPT SMP KASAN [ 23.093180] Modules linked in: [ 23.096464] CPU: 0 PID: 2047 Comm: syz-executor514 Not tainted 4.9.141+ #1 [ 23.103556] task: ffff8801d1a417c0 task.stack: ffff8801cf8a8000 [ 23.109583] RIP: 0010:[] [] __blockdev_direct_IO+0x1a99/0xbd10 [ 23.118866] RSP: 0018:ffff8801cf8af340 EFLAGS: 00010207 [ 23.124280] RAX: 090a0488916916b2 RBX: dffffc0000000000 RCX: 0000000000000000 [ 23.131536] RDX: 0000000000000000 RSI: ffffffff815cf6f1 RDI: 485024448b48b595 [ 23.138773] RBP: ffff8801cf8af660 R08: ffff8801d1a42070 R09: 0000000000000001 [ 23.146012] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 23.153248] R13: 485024448b48b575 R14: 0000000000000000 R15: ffff8801d2a98000 [ 23.160485] FS: 0000000000a5b880(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000 [ 23.168681] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 23.174530] CR2: 0000000020011000 CR3: 00000001d2aa7000 CR4: 00000000001606b0 [ 23.181776] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 23.189011] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 23.196245] Stack: [ 23.198476] 0000000000000246 fffffbfff0604a02 ffff8801cf8af450 ffff8801d2a98098 [ 23.206441] ffff8801cedd0000 0000000000001000 ffffffff83c78930 ffff8801d2a98079 [ 23.214405] ffff8801cf8af550 1513558eafb46824 ffff8801cf8af4b0 0000000000000fff [ 23.222382] Call Trace: [ 23.224942] [] ? ext4_update_bh_state+0xf0/0xf0 [ 23.231227] [] ? sb_init_dio_done_wq+0x80/0x80 [ 23.237431] [] ? ext4_dio_get_block_unwritten_sync+0x100/0x100 [ 23.245071] [] ? ext4_direct_IO+0x1151/0x29c0 [ 23.251189] [] ? __ext4_journal_stop+0xe6/0x1c0 [ 23.257490] [] ? ext4_dio_get_block_unwritten_sync+0x100/0x100 [ 23.265080] [] ext4_direct_IO+0x978/0x29c0 [ 23.270931] [] ? ext4_da_write_begin+0x1020/0x1020 [ 23.277477] [] ? ext4_xattr_security_get+0x32/0x40 [ 23.284025] [] ? ext4_xattr_security_set+0x40/0x40 [ 23.290570] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 23.297289] [] ? mark_held_locks+0xc7/0x130 [ 23.303227] [] ? current_kernel_time64+0xc9/0x120 [ 23.309688] [] ? timespec_trunc+0xc1/0x160 [ 23.315537] [] ? filemap_check_errors+0x90/0xc0 [ 23.321822] [] generic_file_direct_write+0x284/0x510 [ 23.328539] [] ? filemap_write_and_wait_range+0xb0/0xb0 [ 23.335519] [] __generic_file_write_iter+0x21f/0x540 [ 23.342238] [] ? generic_write_checks+0x245/0x410 [ 23.348821] [] ext4_file_write_iter+0x63d/0xd70 [ 23.355113] [] ? ext4_file_open+0x920/0x920 [ 23.361139] [] ? mark_held_locks+0xc7/0x130 [ 23.367091] [] ? mutex_lock_nested+0x6b7/0x900 [ 23.373294] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 23.380118] [] ? mutex_lock_nested+0x5dc/0x900 [ 23.386318] [] vfs_iter_write+0x2d7/0x450 [ 23.392085] [] ? vfs_iter_read+0x3f0/0x3f0 [ 23.397937] [] ? splice_from_pipe_next.part.2+0x226/0x2e0 [ 23.405092] [] iter_file_splice_write+0x5fb/0xb30 [ 23.411554] [] ? vmsplice_to_user+0x1e0/0x1e0 [ 23.417816] [] ? rcu_sync_lockdep_assert+0x73/0xb0 [ 23.424495] [] ? __sb_start_write+0x161/0x300 [ 23.430612] [] ? vmsplice_to_user+0x1e0/0x1e0 [ 23.436728] [] SyS_splice+0xe4d/0x14d0 [ 23.442233] [] ? compat_SyS_vmsplice+0x160/0x160 [ 23.448608] [] ? do_syscall_64+0x48/0x550 [ 23.454373] [] ? compat_SyS_vmsplice+0x160/0x160 [ 23.460744] [] do_syscall_64+0x19f/0x550 [ 23.466423] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 23.473318] Code: 89 84 24 98 02 00 00 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 7a 8e 00 00 4f 8b ac e7 a8 00 00 00 49 8d 7d 20 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 93 8d 00 00 4d 8b 65 20 41 f6 c4 01 0f 85 8c [ 23.500129] RIP [] __blockdev_direct_IO+0x1a99/0xbd10 [ 23.507057] RSP [ 23.511008] ---[ end trace 5e6925c3ad15af0d ]--- [ 23.515751] Kernel panic - not syncing: Fatal exception [ 23.521538] Kernel Offset: disabled [ 23.525145] Rebooting in 86400 seconds..