[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 13.539125] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.286617] random: sshd: uninitialized urandom read (32 bytes read) [ 20.824106] random: sshd: uninitialized urandom read (32 bytes read) [ 21.587812] random: sshd: uninitialized urandom read (32 bytes read) [ 43.831343] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.62' (ECDSA) to the list of known hosts. [ 49.317027] random: sshd: uninitialized urandom read (32 bytes read) executing program [ 49.418633] IPVS: Creating netns size=2536 id=1 executing program [ 49.502216] syz-executor549 (3820) used greatest stack depth: 24312 bytes left executing program [ 49.603374] syz-executor549 (3824) used greatest stack depth: 23448 bytes left executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 67.796030] random: crng init done executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 91.032073] ------------[ cut here ]------------ [ 91.036861] kernel BUG at fs/ext4/inode.c:2630! [ 91.041508] invalid opcode: 0000 [#1] PREEMPT SMP KASAN [ 91.046846] Dumping ftrace buffer: [ 91.050356] (ftrace buffer empty) [ 91.054050] Modules linked in: [ 91.057342] CPU: 0 PID: 6155 Comm: syz-executor549 Not tainted 4.9.100-ge14d1a3 #28 [ 91.065109] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 91.074440] task: ffff8801c45a0000 task.stack: ffff8801c45a8000 [ 91.080467] RIP: 0010:[] [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 91.090186] RSP: 0018:ffff8801c45af3c0 EFLAGS: 00010293 [ 91.095607] RAX: ffff8801c45a0000 RBX: ffffea0006ea9540 RCX: 0000000000000000 [ 91.102851] RDX: 0000000000000000 RSI: ffffffff8173cde8 RDI: ffffea0006ea9548 [ 91.110092] RBP: ffff8801c45af588 R08: ffff8801c45a0938 R09: 0000000000000001 [ 91.117333] R10: 0000000000000000 R11: 1ffff100388b4122 R12: 0000000000000008 [ 91.124575] R13: 0000000000000000 R14: ffff8801c45af6f0 R15: dffffc0000000000 [ 91.131818] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 91.140026] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 91.145880] CR2: 00007fdb6b4f9e78 CR3: 000000000461e000 CR4: 00000000001606f0 [ 91.153128] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 91.160370] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 91.167622] Stack: [ 91.169743] 1ffff100388b5e88 ffff8801c45af6f8 ffff8801c45af460 ffff8801c45af700 [ 91.177720] 00000000c45a08c0 ffff8801b83e6d20 000000020000000c 7fffffffffffffff [ 91.185696] ffff8801c45af4a0 ffff8801c45af708 ffffea0006ea9550 ffffed00388b5edf [ 91.193684] Call Trace: [ 91.196250] [] ? ext4_journalled_zero_new_buffers+0x3a0/0x3a0 [ 91.203771] [] ? __lock_is_held+0xa2/0xf0 [ 91.209552] [] ? __lock_is_held+0xa2/0xf0 [ 91.215327] [] ext4_writepages+0xdb9/0x2e50 [ 91.221273] [] ? do_writepages+0xef/0x1d0 [ 91.227045] [] ? __unwind_start+0x14d/0x3c0 [ 91.232990] [] ? unwind_next_frame+0x86/0xe0 [ 91.239022] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 91.245575] [] ? __unwind_start+0x14d/0x3c0 [ 91.251520] [] ? depot_save_stack+0x132/0x460 [ 91.257636] [] ? ext4_mark_inode_dirty+0xb40/0xb40 [ 91.264187] [] do_writepages+0xef/0x1d0 [ 91.269786] [] ? page_writeback_cpu_online+0x20/0x20 [ 91.276516] [] ? exit_fs+0xe9/0x120 [ 91.281764] [] ? do_exit+0x9bb/0x27c0 [ 91.287189] [] ? do_group_exit+0x111/0x340 [ 91.293044] [] ? get_signal+0x4cf/0x1450 [ 91.298726] [] ? do_signal+0x87/0x19f0 [ 91.304237] [] ? exit_to_usermode_loop+0xe1/0x120 [ 91.310699] [] ? do_syscall_64+0x364/0x490 [ 91.316559] [] ? entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 91.323634] [] __filemap_fdatawrite_range+0x1b3/0x250 [ 91.330449] [] ? replace_page_cache_page+0x620/0x620 [ 91.337173] [] ? ext4_check_all_de+0xf0/0xf0 [ 91.343201] [] filemap_flush+0x23/0x30 [ 91.348712] [] ext4_alloc_da_blocks+0xd9/0x330 [ 91.354927] [] ext4_release_file+0x1ff/0x2e0 [ 91.360961] [] __fput+0x263/0x700 [ 91.366052] [] ____fput+0x15/0x20 [ 91.371132] [] task_work_run+0x10c/0x180 [ 91.376829] [] do_exit+0x9e1/0x27c0 [ 91.382086] [] ? debug_check_no_locks_freed+0x210/0x210 [ 91.389071] [] ? release_task.part.19+0x1210/0x1210 [ 91.395720] [] ? recalc_sigpending+0x72/0x90 [ 91.401753] [] do_group_exit+0x111/0x340 [ 91.407443] [] get_signal+0x4cf/0x1450 [ 91.412957] [] do_signal+0x87/0x19f0 [ 91.418295] [] ? fput+0xd2/0x140 [ 91.423293] [] ? do_sendfile+0x1f9/0xc60 [ 91.428987] [] ? setup_sigcontext+0x7d0/0x7d0 [ 91.435108] [] ? __might_fault+0x18e/0x1d0 [ 91.440965] [] ? __might_fault+0xe4/0x1d0 [ 91.446737] [] ? exit_to_usermode_loop+0xac/0x120 [ 91.453203] [] exit_to_usermode_loop+0xe1/0x120 [ 91.459508] [] do_syscall_64+0x364/0x490 [ 91.465202] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 91.472096] Code: ff 48 8b 75 d0 65 48 33 34 25 28 00 00 00 0f 85 50 02 00 00 48 81 c4 a0 01 00 00 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 18 fc c1 ff <0f> 0b e8 11 fc c1 ff 8b 95 18 ff ff ff 85 d2 75 7a e8 02 fc c1 [ 91.498806] RIP [] mpage_prepare_extent_to_map+0x7f8/0xa40 [ 91.506180] RSP [ 91.510405] ---[ end trace 996a3f710939295b ]--- [ 91.515142] Kernel panic - not syncing: Fatal exception [ 91.520836] Dumping ftrace buffer: [ 91.524358] (ftrace buffer empty) [ 91.528048] Kernel Offset: disabled [ 91.531652] Rebooting in 86400 seconds..