[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 21.432918] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 24.702983] random: sshd: uninitialized urandom read (32 bytes read) [ 25.149910] random: sshd: uninitialized urandom read (32 bytes read) [ 25.911512] random: sshd: uninitialized urandom read (32 bytes read) [ 26.068786] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.51' (ECDSA) to the list of known hosts. [ 31.515073] random: sshd: uninitialized urandom read (32 bytes read) 2018/05/10 19:14:01 parsed 1 programs 2018/05/10 19:14:01 executed programs: 0 [ 31.984470] IPVS: ftp: loaded support on port[0] = 21 [ 31.987401] IPVS: ftp: loaded support on port[0] = 21 [ 31.999228] IPVS: ftp: loaded support on port[0] = 21 [ 32.034380] IPVS: ftp: loaded support on port[0] = 21 [ 32.042778] IPVS: ftp: loaded support on port[0] = 21 [ 32.043669] IPVS: ftp: loaded support on port[0] = 21 [ 32.061918] IPVS: ftp: loaded support on port[0] = 21 [ 32.068686] F2FS-fs (loop1): Magic Mismatch, valid(0xf2f52010) - read(0x0) [ 32.075863] F2FS-fs (loop1): Can't find valid F2FS filesystem in 1th superblock [ 32.094537] WARNING: CPU: 1 PID: 4572 at mm/slab_common.c:996 kmalloc_slab+0x56/0x70 [ 32.102455] Kernel panic - not syncing: panic_on_warn set ... [ 32.102455] [ 32.109811] CPU: 1 PID: 4572 Comm: syz-executor1 Not tainted 4.17.0-rc4+ #40 [ 32.116982] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.126321] Call Trace: [ 32.128909] dump_stack+0x1b9/0x294 [ 32.132531] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.136963] IPVS: ftp: loaded support on port[0] = 21 [ 32.137709] ? slab_caches_to_rcu_destroy_workfn+0xb0/0xc0 [ 32.137722] panic+0x22f/0x4de [ 32.137734] ? add_taint.cold.5+0x16/0x16 [ 32.155859] ? __warn.cold.8+0x148/0x1b3 [ 32.159904] ? __warn.cold.8+0x117/0x1b3 [ 32.163950] ? kmalloc_slab+0x56/0x70 [ 32.167735] __warn.cold.8+0x163/0x1b3 [ 32.171625] ? kmalloc_slab+0x56/0x70 [ 32.175421] report_bug+0x252/0x2d0 [ 32.179037] do_error_trap+0x1de/0x490 [ 32.182917] ? math_error+0x420/0x420 [ 32.183498] F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0) [ 32.186712] ? debug_check_no_locks_freed+0x310/0x310 [ 32.186727] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.186737] do_invalid_op+0x1b/0x20 [ 32.186750] invalid_op+0x14/0x20 [ 32.193804] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock [ 32.198950] RIP: 0010:kmalloc_slab+0x56/0x70 [ 32.198956] RSP: 0018:ffff8801ae926e08 EFLAGS: 00010246 [ 32.198965] RAX: 0000000000000000 RBX: ffff8801b21c9540 RCX: ffffffff82f163e4 [ 32.198969] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000001e3a030000 [ 32.198974] RBP: ffff8801ae926e08 R08: ffff8801b26a0040 R09: ffffed003b5e46c2 [ 32.198984] R10: ffffed003b5e46c2 R11: ffff8801daf23613 R12: 0000001e3a030000 [ 32.257101] R13: ffff8801b21ca298 R14: 0000000000000000 R15: 00000000014080c0 [ 32.264370] ? get_valid_checkpoint+0x314/0x1e90 [ 32.269113] __kmalloc+0x25/0x760 [ 32.272550] ? graph_lock+0x170/0x170 [ 32.276345] ? get_valid_checkpoint+0x37f/0x1e90 [ 32.281086] get_valid_checkpoint+0x37f/0x1e90 [ 32.285651] ? recover_orphan_inodes+0x11b0/0x11b0 [ 32.290564] ? graph_lock+0x170/0x170 [ 32.292631] F2FS-fs (loop0): Failed to get valid F2FS checkpoint [ 32.294353] ? lock_downgrade+0x8e0/0x8e0 [ 32.294361] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.294373] ? kasan_check_read+0x11/0x20 [ 32.294383] ? __lock_is_held+0xb5/0x140 [ 32.294390] ? do_raw_spin_lock+0xc1/0x200 [ 32.294404] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.294412] ? f2fs_iget+0x68e/0x3d10 [ 32.294426] ? f2fs_inode_chksum_set+0xf0/0xf0 [ 32.294438] ? lock_downgrade+0x8e0/0x8e0 [ 32.339604] ? mark_held_locks+0xc9/0x160 [ 32.342696] F2FS-fs (loop0): Magic Mismatch, valid(0xf2f52010) - read(0x0) [ 32.343733] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.343744] ? _raw_spin_unlock_irqrestore+0x74/0xc0 [ 32.343752] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.343760] ? trace_hardirqs_on+0xd/0x10 [ 32.343771] ? percpu_counter_cpu_dead+0x1c0/0x1c0 [ 32.343779] ? __raw_spin_lock_init+0x1c/0x100 [ 32.343787] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.343796] ? lockdep_init_map+0x9/0x10 [ 32.343811] f2fs_fill_super+0x318f/0x7bf0 [ 32.350869] F2FS-fs (loop0): Can't find valid F2FS filesystem in 1th superblock [ 32.355420] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.355444] ? f2fs_commit_super+0x400/0x400 [ 32.355456] ? lock_downgrade+0x8e0/0x8e0 [ 32.376863] F2FS-fs (loop0): Failed to get valid F2FS checkpoint [ 32.379173] ? lock_release+0xa10/0xa10 [ 32.379184] ? check_same_owner+0x320/0x320 [ 32.379195] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 32.379204] ? widen_string+0xd8/0x2d0 [ 32.379214] ? rcu_note_context_switch+0x710/0x710 [ 32.379223] ? format_decode+0xae0/0xae0 [ 32.379231] ? graph_lock+0x170/0x170 [ 32.379244] ? widen_string+0x2d0/0x2d0 [ 32.379259] ? sget_userns+0x2dd/0xf00 [ 32.415801] F2FS-fs (loop7): Magic Mismatch, valid(0xf2f52010) - read(0x0) [ 32.419605] ? find_held_lock+0x13f/0x1c0 [ 32.419619] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.419629] ? bdev_name.isra.7+0x1a1/0x1f0 [ 32.419639] ? pointer+0x1b0/0xa20 [ 32.419648] ? netdev_bits+0xb0/0xb0 [ 32.419655] ? format_decode+0x1a9/0xae0 [ 32.419664] ? set_precision+0xe0/0xe0 [ 32.419675] ? __sanitizer_cov_trace_switch+0x53/0x90 [ 32.419689] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 32.423696] F2FS-fs (loop7): Can't find valid F2FS filesystem in 1th superblock [ 32.427986] ? vsnprintf+0x242/0x1b40 [ 32.427998] ? pointer+0xa20/0xa20 [ 32.428010] ? snprintf+0xa5/0xd0 [ 32.428018] ? vsprintf+0x40/0x40 [ 32.428028] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 32.428042] ? set_blocksize+0x2c4/0x350 [ 32.534716] mount_bdev+0x30c/0x3e0 [ 32.538326] ? f2fs_commit_super+0x400/0x400 [ 32.542713] ? mount_bdev+0x30c/0x3e0 [ 32.546507] ? f2fs_commit_super+0x400/0x400 [ 32.550908] f2fs_mount+0x34/0x40 [ 32.554346] mount_fs+0xae/0x328 [ 32.557695] vfs_kern_mount.part.34+0xd4/0x4d0 [ 32.562258] ? may_umount+0xb0/0xb0 [ 32.565876] ? _raw_read_unlock+0x22/0x30 [ 32.570003] ? __get_fs_type+0x97/0xc0 [ 32.573874] do_mount+0x564/0x3070 [ 32.577398] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.581789] ? copy_mount_string+0x40/0x40 [ 32.586004] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.591006] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 32.595747] ? retint_kernel+0x10/0x10 [ 32.599629] ? copy_mount_options+0x1e3/0x380 [ 32.604116] ? copy_mount_options+0x1f0/0x380 [ 32.608619] ? copy_mount_options+0x200/0x380 [ 32.613101] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.618635] ? copy_mount_options+0x285/0x380 [ 32.623203] ksys_mount+0x12d/0x140 [ 32.626811] __x64_sys_mount+0xbe/0x150 [ 32.630766] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.635766] do_syscall_64+0x1b1/0x800 [ 32.639634] ? finish_task_switch+0x1ca/0x810 [ 32.644111] ? syscall_return_slowpath+0x5c0/0x5c0 [ 32.649022] ? syscall_return_slowpath+0x30f/0x5c0 [ 32.653935] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 32.659286] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.664112] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 32.669292] RIP: 0033:0x4583aa [ 32.672460] RSP: 002b:00007f33f012aba8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 32.680148] RAX: ffffffffffffffda RBX: 0000000020000040 RCX: 00000000004583aa [ 32.687406] RDX: 0000000020000040 RSI: 0000000020000080 RDI: 00007f33f012abf0 [ 32.694665] RBP: 0000000000000001 R08: 00000000200000c0 R09: 0000000020000040 [ 32.701950] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003 [ 32.709303] R13: 0000000000000001 R14: 00000000006fe2d0 R15: 0000000000000000 [ 32.717419] Dumping ftrace buffer: [ 32.721042] (ftrace buffer empty) [ 32.724737] Kernel Offset: disabled [ 32.728354] Rebooting in 86400 seconds..