[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 19.001676] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 19.285999] random: sshd: uninitialized urandom read (32 bytes read) [ 19.586503] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.461424] random: sshd: uninitialized urandom read (32 bytes read) [ 20.621526] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.50' (ECDSA) to the list of known hosts. [ 26.075975] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program [ 26.168282] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. [ 26.222586] ================================================================== [ 26.230092] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 26.236225] Read of size 46522 at addr ffff8801a999896d by task syz-executor880/4548 [ 26.244172] [ 26.245814] CPU: 0 PID: 4548 Comm: syz-executor880 Not tainted 4.18.0-rc3+ #137 [ 26.253590] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.262962] Call Trace: [ 26.265548] dump_stack+0x1c9/0x2b4 [ 26.269176] ? dump_stack_print_info.cold.2+0x52/0x52 [ 26.274796] ? printk+0xa7/0xcf [ 26.278077] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 26.282827] ? pdu_read+0x90/0xd0 [ 26.286265] print_address_description+0x6c/0x20b [ 26.291106] ? pdu_read+0x90/0xd0 [ 26.294548] kasan_report.cold.7+0x242/0x2fe [ 26.298946] check_memory_region+0x13e/0x1b0 [ 26.303347] memcpy+0x23/0x50 [ 26.306449] pdu_read+0x90/0xd0 [ 26.309714] p9pdu_readf+0x579/0x2170 [ 26.313504] ? p9pdu_writef+0xe0/0xe0 [ 26.317307] ? __fget+0x414/0x670 [ 26.320755] ? rcu_is_watching+0x61/0x150 [ 26.324888] ? expand_files.part.8+0x9c0/0x9c0 [ 26.329481] ? rcu_read_lock_sched_held+0x108/0x120 [ 26.334493] ? p9_fd_show_options+0x1c0/0x1c0 [ 26.338979] p9_client_create+0xde0/0x16c9 [ 26.343211] ? p9_client_read+0xc60/0xc60 [ 26.347360] ? find_held_lock+0x36/0x1c0 [ 26.351432] ? __lockdep_init_map+0x105/0x590 [ 26.355918] ? kasan_check_write+0x14/0x20 [ 26.360149] ? __init_rwsem+0x1cc/0x2a0 [ 26.364109] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 26.369121] ? rcu_read_lock_sched_held+0x108/0x120 [ 26.374131] ? __kmalloc_track_caller+0x5f5/0x760 [ 26.378964] ? save_stack+0xa9/0xd0 [ 26.382578] ? save_stack+0x43/0xd0 [ 26.386191] ? kasan_kmalloc+0xc4/0xe0 [ 26.390062] ? kmem_cache_alloc_trace+0x152/0x780 [ 26.394904] ? memcpy+0x45/0x50 [ 26.398180] v9fs_session_init+0x21a/0x1a80 [ 26.402494] ? find_held_lock+0x36/0x1c0 [ 26.406548] ? v9fs_show_options+0x7e0/0x7e0 [ 26.410962] ? kasan_check_read+0x11/0x20 [ 26.415094] ? rcu_is_watching+0x8c/0x150 [ 26.419236] ? rcu_pm_notify+0xc0/0xc0 [ 26.423112] ? v9fs_mount+0x61/0x900 [ 26.426819] ? rcu_read_lock_sched_held+0x108/0x120 [ 26.431914] ? kmem_cache_alloc_trace+0x616/0x780 [ 26.436745] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 26.442268] v9fs_mount+0x7c/0x900 [ 26.445801] mount_fs+0xae/0x328 [ 26.449163] vfs_kern_mount.part.34+0xdc/0x4e0 [ 26.453732] ? may_umount+0xb0/0xb0 [ 26.457343] ? _raw_read_unlock+0x22/0x30 [ 26.461889] ? __get_fs_type+0x97/0xc0 [ 26.465763] do_mount+0x581/0x30e0 [ 26.469312] ? copy_mount_string+0x40/0x40 [ 26.473536] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.478277] ? retint_kernel+0x10/0x10 [ 26.482164] ? copy_mount_options+0x1e3/0x380 [ 26.486641] ? copy_mount_options+0x1f0/0x380 [ 26.491130] ? copy_mount_options+0x1f0/0x380 [ 26.495620] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.501138] ? copy_mount_options+0x285/0x380 [ 26.505634] ksys_mount+0x12d/0x140 [ 26.509248] __x64_sys_mount+0xbe/0x150 [ 26.513206] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.518710] do_syscall_64+0x1b9/0x820 [ 26.522588] ? syscall_return_slowpath+0x5e0/0x5e0 [ 26.527507] ? syscall_return_slowpath+0x31d/0x5e0 [ 26.532425] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.537960] ? retint_user+0x18/0x18 [ 26.541928] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.546760] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.551931] RIP: 0033:0x440959 [ 26.555099] Code: e8 8c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 26.574277] RSP: 002b:00007ffe30923f18 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 26.581977] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440959 [ 26.589260] RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 [ 26.596528] RBP: 0000000000000000 R08: 0000000020000180 R09: 00000000004002c8 [ 26.603800] R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000006667 [ 26.611062] R13: 0000000000401eb0 R14: 0000000000000000 R15: 0000000000000000 [ 26.618332] [ 26.619942] Allocated by task 4548: [ 26.623554] save_stack+0x43/0xd0 [ 26.626989] kasan_kmalloc+0xc4/0xe0 [ 26.630704] __kmalloc+0x14e/0x760 [ 26.634230] p9_fcall_alloc+0x1e/0x90 [ 26.638018] p9_client_prepare_req.part.8+0x754/0xcd0 [ 26.643195] p9_client_rpc+0x1bd/0x1400 [ 26.647163] p9_client_create+0xd09/0x16c9 [ 26.651410] v9fs_session_init+0x21a/0x1a80 [ 26.655710] v9fs_mount+0x7c/0x900 [ 26.659242] mount_fs+0xae/0x328 [ 26.662587] vfs_kern_mount.part.34+0xdc/0x4e0 [ 26.667150] do_mount+0x581/0x30e0 [ 26.670675] ksys_mount+0x12d/0x140 [ 26.674291] __x64_sys_mount+0xbe/0x150 [ 26.678246] do_syscall_64+0x1b9/0x820 [ 26.682126] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.687291] [ 26.688896] Freed by task 0: [ 26.691890] (stack is not available) [ 26.695577] [ 26.697195] The buggy address belongs to the object at ffff8801a9998940 [ 26.697195] which belongs to the cache kmalloc-16384 of size 16384 [ 26.710180] The buggy address is located 45 bytes inside of [ 26.710180] 16384-byte region [ffff8801a9998940, ffff8801a999c940) [ 26.722128] The buggy address belongs to the page: [ 26.727048] page:ffffea0006a66600 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 26.737012] flags: 0x2fffc0000008100(slab|head) [ 26.741673] raw: 02fffc0000008100 ffffea0006b88c08 ffff8801da801c48 ffff8801da802200 [ 26.749554] raw: 0000000000000000 ffff8801a9998940 0000000100000001 0000000000000000 [ 26.757419] page dumped because: kasan: bad access detected [ 26.763106] [ 26.764723] Memory state around the buggy address: [ 26.769638] ffff8801a999a800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.776998] ffff8801a999a880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.784389] >ffff8801a999a900: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 26.791726] ^ [ 26.798197] ffff8801a999a980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.805534] ffff8801a999aa00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.812872] ================================================================== [ 26.820213] Disabling lock debugging due to kernel taint [ 26.825719] Kernel panic - not syncing: panic_on_warn set ... [ 26.825719] [ 26.833089] CPU: 0 PID: 4548 Comm: syz-executor880 Tainted: G B 4.18.0-rc3+ #137 [ 26.841910] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.851243] Call Trace: [ 26.853827] dump_stack+0x1c9/0x2b4 [ 26.857437] ? dump_stack_print_info.cold.2+0x52/0x52 [ 26.863749] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.868485] panic+0x238/0x4e7 [ 26.871657] ? add_taint.cold.5+0x16/0x16 [ 26.875785] ? do_raw_spin_unlock+0xa7/0x2f0 [ 26.880198] ? pdu_read+0x90/0xd0 [ 26.883632] kasan_end_report+0x47/0x4f [ 26.887587] kasan_report.cold.7+0x76/0x2fe [ 26.891887] check_memory_region+0x13e/0x1b0 [ 26.896283] memcpy+0x23/0x50 [ 26.899387] pdu_read+0x90/0xd0 [ 26.902659] p9pdu_readf+0x579/0x2170 [ 26.906460] ? p9pdu_writef+0xe0/0xe0 [ 26.910239] ? __fget+0x414/0x670 [ 26.913685] ? rcu_is_watching+0x61/0x150 [ 26.917824] ? expand_files.part.8+0x9c0/0x9c0 [ 26.922400] ? rcu_read_lock_sched_held+0x108/0x120 [ 26.927410] ? p9_fd_show_options+0x1c0/0x1c0 [ 26.931897] p9_client_create+0xde0/0x16c9 [ 26.936126] ? p9_client_read+0xc60/0xc60 [ 26.940253] ? find_held_lock+0x36/0x1c0 [ 26.944306] ? __lockdep_init_map+0x105/0x590 [ 26.948788] ? kasan_check_write+0x14/0x20 [ 26.953044] ? __init_rwsem+0x1cc/0x2a0 [ 26.957012] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 26.962025] ? rcu_read_lock_sched_held+0x108/0x120 [ 26.967039] ? __kmalloc_track_caller+0x5f5/0x760 [ 26.971881] ? save_stack+0xa9/0xd0 [ 26.975488] ? save_stack+0x43/0xd0 [ 26.979094] ? kasan_kmalloc+0xc4/0xe0 [ 26.982960] ? kmem_cache_alloc_trace+0x152/0x780 [ 26.987780] ? memcpy+0x45/0x50 [ 26.991055] v9fs_session_init+0x21a/0x1a80 [ 26.995363] ? find_held_lock+0x36/0x1c0 [ 26.999408] ? v9fs_show_options+0x7e0/0x7e0 [ 27.003803] ? kasan_check_read+0x11/0x20 [ 27.007928] ? rcu_is_watching+0x8c/0x150 [ 27.012056] ? rcu_pm_notify+0xc0/0xc0 [ 27.015931] ? v9fs_mount+0x61/0x900 [ 27.019627] ? rcu_read_lock_sched_held+0x108/0x120 [ 27.024625] ? kmem_cache_alloc_trace+0x616/0x780 [ 27.029462] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 27.034981] v9fs_mount+0x7c/0x900 [ 27.038515] mount_fs+0xae/0x328 [ 27.041894] vfs_kern_mount.part.34+0xdc/0x4e0 [ 27.046480] ? may_umount+0xb0/0xb0 [ 27.050105] ? _raw_read_unlock+0x22/0x30 [ 27.054245] ? __get_fs_type+0x97/0xc0 [ 27.058123] do_mount+0x581/0x30e0 [ 27.061649] ? copy_mount_string+0x40/0x40 [ 27.065870] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.070608] ? retint_kernel+0x10/0x10 [ 27.074479] ? copy_mount_options+0x1e3/0x380 [ 27.078955] ? copy_mount_options+0x1f0/0x380 [ 27.083428] ? copy_mount_options+0x1f0/0x380 [ 27.087904] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.093421] ? copy_mount_options+0x285/0x380 [ 27.097896] ksys_mount+0x12d/0x140 [ 27.101503] __x64_sys_mount+0xbe/0x150 [ 27.105467] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.110463] do_syscall_64+0x1b9/0x820 [ 27.114353] ? syscall_return_slowpath+0x5e0/0x5e0 [ 27.119263] ? syscall_return_slowpath+0x31d/0x5e0 [ 27.124182] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.129708] ? retint_user+0x18/0x18 [ 27.133405] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.138228] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.143395] RIP: 0033:0x440959 [ 27.146569] Code: e8 8c b3 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 27.165689] RSP: 002b:00007ffe30923f18 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 27.173385] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440959 [ 27.180635] RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 [ 27.187893] RBP: 0000000000000000 R08: 0000000020000180 R09: 00000000004002c8 [ 27.195148] R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000006667 [ 27.202401] R13: 0000000000401eb0 R14: 0000000000000000 R15: 0000000000000000 [ 27.210124] Dumping ftrace buffer: [ 27.213642] (ftrace buffer empty) [ 27.217328] Kernel Offset: disabled [ 27.220947] Rebooting in 86400 seconds..