[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.955148] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.787029] random: sshd: uninitialized urandom read (32 bytes read, 36 bits of entropy available) [ 21.146181] random: sshd: uninitialized urandom read (32 bytes read, 37 bits of entropy available) [ 22.036213] random: sshd: uninitialized urandom read (32 bytes read, 107 bits of entropy available) [ 22.214117] random: sshd: uninitialized urandom read (32 bytes read, 113 bits of entropy available) Warning: Permanently added '10.128.0.20' (ECDSA) to the list of known hosts. [ 27.687641] random: sshd: uninitialized urandom read (32 bytes read, 120 bits of entropy available) executing program [ 27.785922] ================================================================== [ 27.793300] BUG: KASAN: slab-out-of-bounds in sg_remove_request+0xf9/0x110 [ 27.800289] Read of size 8 at addr ffff8801d303b140 by task syzkaller148856/3311 [ 27.807789] [ 27.809386] CPU: 1 PID: 3311 Comm: syzkaller148856 Not tainted 4.4.113-ge70c132 #34 [ 27.817144] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.826471] 0000000000000000 8cf95c9b540b97d9 ffff8801d17379f0 ffffffff81d0278d [ 27.834436] ffffea00074c0ec0 ffff8801d303b140 0000000000000000 ffff8801d303b140 [ 27.842399] ffff8801d0d70238 ffff8801d1737a28 ffffffff814fd053 ffff8801d303b140 [ 27.850358] Call Trace: [ 27.852913] [] dump_stack+0xc1/0x124 [ 27.858248] [] print_address_description+0x73/0x260 [ 27.864880] [] kasan_report+0x285/0x370 [ 27.870473] [] ? sg_remove_request+0xf9/0x110 [ 27.876585] [] __asan_report_load8_noabort+0x14/0x20 [ 27.883302] [] sg_remove_request+0xf9/0x110 [ 27.889243] [] sg_finish_rem_req+0x295/0x340 [ 27.895268] [] sg_read+0xa1b/0x1490 [ 27.900512] [] ? __check_object_size+0x154/0x35b [ 27.907493] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 27.914125] [] ? fsnotify+0xee0/0xee0 [ 27.919544] [] ? avc_policy_seqno+0x9/0x20 [ 27.925396] [] do_loop_readv_writev+0x141/0x1e0 [ 27.931680] [] ? security_file_permission+0x89/0x1e0 [ 27.938398] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 27.945030] [] ? sg_proc_seq_show_debug+0xda0/0xda0 [ 27.951663] [] do_readv_writev+0x5dd/0x6e0 [ 27.957514] [] ? vfs_write+0x530/0x530 [ 27.963027] [] ? _raw_spin_unlock+0x2c/0x50 [ 27.968965] [] ? fasync_insert_entry+0x147/0x2e0 [ 27.975339] [] ? fasync_helper+0x7a/0xb0 [ 27.981019] [] ? sg_fasync+0x8d/0xb0 [ 27.987234] [] ? do_vfs_ioctl+0x468/0xee0 [ 27.992998] [] ? ioctl_preallocate+0x1f0/0x1f0 [ 27.999196] [] vfs_readv+0x78/0xb0 [ 28.004350] [] SyS_readv+0xd9/0x240 [ 28.009592] [] ? rw_copy_check_uvector+0x2b0/0x2b0 [ 28.016138] [] ? lockdep_sys_exit_thunk+0x12/0x14 [ 28.022602] [] entry_SYSCALL_64_fastpath+0x1c/0x98 [ 28.029150] [ 28.030751] Allocated by task 0: [ 28.034078] (stack is not available) [ 28.037756] [ 28.039349] Freed by task 0: [ 28.042332] (stack is not available) [ 28.046009] [ 28.047605] The buggy address belongs to the object at ffff8801d303b100 [ 28.047605] which belongs to the cache fasync_cache of size 96 [ 28.060227] The buggy address is located 64 bytes inside of [ 28.060227] 96-byte region [ffff8801d303b100, ffff8801d303b160) [ 28.071906] The buggy address belongs to the page: [ 28.085297] BUG: unable to handle kernel paging request at ffffebe000000028 [ 28.092680] IP: [] __list_del_entry+0x30/0x1d0 [ 28.098951] PGD 0 [ 28.101222] Oops: 0000 [#1] PREEMPT SMP KASAN [ 28.106218] Dumping ftrace buffer: [ 28.109742] (ftrace buffer empty) [ 28.113445] Modules linked in: [ 28.116756] CPU: 0 PID: 7 Comm: rcu_preempt Not tainted 4.4.113-ge70c132 #34 [ 28.123929] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.133275] task: ffff8801da3717c0 task.stack: ffff8801da388000 [ 28.139320] RIP: 0010:[] [] __list_del_entry+0x30/0x1d0 [ 28.148036] RSP: 0018:ffff8801da38f918 EFLAGS: 00010246 [ 28.153479] RAX: dffffc0000000000 RBX: ffffebe000000020 RCX: ffffebe000000020 [ 28.160742] RDX: ffffebe000000020 RSI: ffff8801da372030 RDI: ffffebe000000028 [ 28.168002] RBP: ffff8801da38f930 R08: 0000000000000001 R09: ffffffff850e5920 [ 28.175273] R10: 0000000000000001 R11: 1ffff1003b471ef2 R12: ffff8801d1721900 [ 28.182534] R13: 0000000080000000 R14: 000077ff80000000 R15: dffffc0000000000 [ 28.189798] FS: 0000000000000000(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 [ 28.198018] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 28.203896] CR2: ffffebe000000028 CR3: 00000000b41f2000 CR4: 0000000000160670 [ 28.211163] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 28.218425] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 28.225690] Stack: [ 28.227834] 0000000000000000 ffffebe000000020 ffff8801d1721900 ffff8801da38f948 [ 28.235871] ffffffff81d62add 0000000000000000 ffff8801da38f978 ffffffff810e93f3 [ 28.243912] ffff8801d1721900 ffff8801d1721c40 0000000000000000 0000000000000000 [ 28.251950] Call Trace: [ 28.254527] [] list_del+0xd/0x70 [ 28.259541] [] pgd_free+0x63/0x100 [ 28.264730] [] __mmdrop+0x66/0x260 [ 28.269923] [] finish_task_switch+0x213/0x4e0 [ 28.276069] [] ? finish_task_switch+0x1bb/0x4e0 [ 28.282392] [] ? __schedule+0xa26/0x1c70 [ 28.288101] [] __schedule+0xa9d/0x1c70 [ 28.293643] [] schedule+0x7a/0x1b0 [ 28.298832] [] schedule_timeout+0x356/0x970 [ 28.304805] [] ? prepare_to_wait_event+0x114/0x420 [ 28.311386] [] ? usleep_range+0x140/0x140 [ 28.317184] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.324023] [] ? init_timer_key+0x360/0x360 [ 28.329996] [] ? __might_sleep+0x90/0x1a0 [ 28.335794] [] rcu_gp_kthread+0xdf2/0x2200 [ 28.341679] [] ? force_qs_rnp+0x3e0/0x3e0 [ 28.347473] [] ? _raw_spin_unlock_irq+0x27/0x50 [ 28.353795] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.360641] [] ? _raw_spin_unlock_irq+0x38/0x50 [ 28.366960] [] ? __schedule+0x1006/0x1c70 [ 28.372756] [] ? ___preempt_schedule+0x12/0x14 [ 28.378992] [] ? prepare_to_wait_event+0x420/0x420 [ 28.385569] [] ? __kthread_parkme+0x167/0x230 [ 28.391716] [] kthread+0x268/0x300 [ 28.396907] [] ? force_qs_rnp+0x3e0/0x3e0 [ 28.402706] [] ? kthread_create_on_node+0x400/0x400 [ 28.409373] [] ? kthread_create_on_node+0x400/0x400 [ 28.416037] [] ret_from_fork+0x55/0x80 [ 28.421575] [] ? kthread_create_on_node+0x400/0x400 [ 28.428227] Code: 00 00 fc ff df 48 89 f9 55 48 83 c7 08 48 89 fa 48 89 e5 41 54 48 c1 ea 03 53 48 83 ec 08 80 3c 02 00 0f 85 87 01 00 00 48 89 ca <48> 8b 59 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 80 3c 02 [ 28.455603] RIP [] __list_del_entry+0x30/0x1d0 [ 28.461962] RSP [ 28.465577] CR2: ffffebe000000028 [ 28.469016] ---[ end trace 2b1767a38770374c ]--- [ 28.473761] Kernel panic - not syncing: Fatal exception [ 29.613044] Shutting down cpus with NMI [ 29.617685] Dumping ftrace buffer: [ 29.621201] (ftrace buffer empty) [ 29.624879] Kernel Offset: disabled [ 29.628471] Rebooting in 86400 seconds..