[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.000313] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 23.767639] random: sshd: uninitialized urandom read (32 bytes read) [ 24.202891] random: sshd: uninitialized urandom read (32 bytes read) [ 25.071127] random: sshd: uninitialized urandom read (32 bytes read) [ 25.228775] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.34' (ECDSA) to the list of known hosts. [ 30.700586] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program [ 30.798574] ================================================================== [ 30.806069] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 30.812211] Read of size 58751 at addr ffff8801bd1887ed by task syz-executor245/4535 [ 30.820076] [ 30.821698] CPU: 1 PID: 4535 Comm: syz-executor245 Not tainted 4.18.0-rc4+ #141 [ 30.829141] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.838479] Call Trace: [ 30.841055] dump_stack+0x1c9/0x2b4 [ 30.844673] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.849863] ? printk+0xa7/0xcf [ 30.853140] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 30.857894] ? pdu_read+0x90/0xd0 [ 30.861341] print_address_description+0x6c/0x20b [ 30.866171] ? pdu_read+0x90/0xd0 [ 30.869616] kasan_report.cold.7+0x242/0x2fe [ 30.874032] check_memory_region+0x13e/0x1b0 [ 30.878440] memcpy+0x23/0x50 [ 30.881537] pdu_read+0x90/0xd0 [ 30.884804] p9pdu_readf+0x579/0x2170 [ 30.888597] ? p9pdu_writef+0xe0/0xe0 [ 30.892380] ? __fget+0x414/0x670 [ 30.895822] ? rcu_is_watching+0x61/0x150 [ 30.899952] ? expand_files.part.8+0x9c0/0x9c0 [ 30.904539] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.909551] ? p9_fd_show_options+0x1c0/0x1c0 [ 30.914042] p9_client_create+0xde0/0x16c9 [ 30.918279] ? p9_client_read+0xc60/0xc60 [ 30.922427] ? find_held_lock+0x36/0x1c0 [ 30.926478] ? __lockdep_init_map+0x105/0x590 [ 30.930962] ? kasan_check_write+0x14/0x20 [ 30.935179] ? __init_rwsem+0x1cc/0x2a0 [ 30.939147] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 30.944154] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.949156] ? __kmalloc_track_caller+0x5f5/0x760 [ 30.953987] ? save_stack+0xa9/0xd0 [ 30.957600] ? save_stack+0x43/0xd0 [ 30.961211] ? kasan_kmalloc+0xc4/0xe0 [ 30.965082] ? kmem_cache_alloc_trace+0x152/0x780 [ 30.969910] ? memcpy+0x45/0x50 [ 30.973184] v9fs_session_init+0x21a/0x1a80 [ 30.977491] ? find_held_lock+0x36/0x1c0 [ 30.981543] ? v9fs_show_options+0x7e0/0x7e0 [ 30.985955] ? kasan_check_read+0x11/0x20 [ 30.990088] ? rcu_is_watching+0x8c/0x150 [ 30.994237] ? rcu_pm_notify+0xc0/0xc0 [ 30.998121] ? v9fs_mount+0x61/0x900 [ 31.001818] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.006834] ? kmem_cache_alloc_trace+0x616/0x780 [ 31.011669] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 31.017193] v9fs_mount+0x7c/0x900 [ 31.020718] mount_fs+0xae/0x328 [ 31.024071] vfs_kern_mount.part.34+0xdc/0x4e0 [ 31.028645] ? may_umount+0xb0/0xb0 [ 31.032260] ? _raw_read_unlock+0x22/0x30 [ 31.036403] ? __get_fs_type+0x97/0xc0 [ 31.040299] do_mount+0x581/0x30e0 [ 31.043825] ? copy_mount_string+0x40/0x40 [ 31.048053] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.052810] ? retint_kernel+0x10/0x10 [ 31.056690] ? copy_mount_options+0x213/0x380 [ 31.061168] ? write_comp_data+0x70/0x70 [ 31.065212] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.070745] ? copy_mount_options+0x285/0x380 [ 31.075227] ksys_mount+0x12d/0x140 [ 31.078839] __x64_sys_mount+0xbe/0x150 [ 31.082799] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.087810] do_syscall_64+0x1b9/0x820 [ 31.091862] ? syscall_return_slowpath+0x5e0/0x5e0 [ 31.096778] ? syscall_return_slowpath+0x31d/0x5e0 [ 31.101697] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 31.107060] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.111895] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.117070] RIP: 0033:0x4401a9 [ 31.120245] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 31.139438] RSP: 002b:00007ffc5202d528 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 31.147145] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 00000000004401a9 [ 31.154416] RDX: 0000000020000140 RSI: 0000000020000100 RDI: 0000000000000000 [ 31.161678] RBP: 0030656c69662f2e R08: 00000000200002c0 R09: 0000000000000001 [ 31.168932] R10: 0000000000000000 R11: 0000000000000206 R12: 64663d736e617274 [ 31.176195] R13: 0000040000000002 R14: 0000000000000000 R15: 0000000000000000 [ 31.183456] [ 31.185072] Allocated by task 4535: [ 31.188758] save_stack+0x43/0xd0 [ 31.192192] kasan_kmalloc+0xc4/0xe0 [ 31.195891] __kmalloc+0x14e/0x760 [ 31.199416] p9_fcall_alloc+0x1e/0x90 [ 31.203210] p9_client_prepare_req.part.8+0x754/0xcd0 [ 31.208386] p9_client_rpc+0x1bd/0x1400 [ 31.212347] p9_client_create+0xd09/0x16c9 [ 31.216564] v9fs_session_init+0x21a/0x1a80 [ 31.220875] v9fs_mount+0x7c/0x900 [ 31.224402] mount_fs+0xae/0x328 [ 31.227759] vfs_kern_mount.part.34+0xdc/0x4e0 [ 31.232333] do_mount+0x581/0x30e0 [ 31.235865] ksys_mount+0x12d/0x140 [ 31.239476] __x64_sys_mount+0xbe/0x150 [ 31.243445] do_syscall_64+0x1b9/0x820 [ 31.247319] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.252482] [ 31.254100] Freed by task 0: [ 31.257098] (stack is not available) [ 31.260798] [ 31.262409] The buggy address belongs to the object at ffff8801bd1887c0 [ 31.262409] which belongs to the cache kmalloc-16384 of size 16384 [ 31.275413] The buggy address is located 45 bytes inside of [ 31.275413] 16384-byte region [ffff8801bd1887c0, ffff8801bd18c7c0) [ 31.287361] The buggy address belongs to the page: [ 31.292291] page:ffffea0006f46200 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 31.302246] flags: 0x2fffc0000008100(slab|head) [ 31.306901] raw: 02fffc0000008100 ffffea0006efb408 ffff8801da801c48 ffff8801da802200 [ 31.314773] raw: 0000000000000000 ffff8801bd1887c0 0000000100000001 0000000000000000 [ 31.322648] page dumped because: kasan: bad access detected [ 31.328340] [ 31.329945] Memory state around the buggy address: [ 31.334856] ffff8801bd18a680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.342196] ffff8801bd18a700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.349537] >ffff8801bd18a780: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 31.356896] ^ [ 31.363388] ffff8801bd18a800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.370736] ffff8801bd18a880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.378073] ================================================================== [ 31.385762] Disabling lock debugging due to kernel taint [ 31.391309] Kernel panic - not syncing: panic_on_warn set ... [ 31.391309] [ 31.398685] CPU: 1 PID: 4535 Comm: syz-executor245 Tainted: G B 4.18.0-rc4+ #141 [ 31.407516] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.416852] Call Trace: [ 31.419431] dump_stack+0x1c9/0x2b4 [ 31.423047] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.428245] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.433023] panic+0x238/0x4e7 [ 31.436232] ? add_taint.cold.5+0x16/0x16 [ 31.440381] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.444780] ? pdu_read+0x90/0xd0 [ 31.448225] kasan_end_report+0x47/0x4f [ 31.452185] kasan_report.cold.7+0x76/0x2fe [ 31.456490] check_memory_region+0x13e/0x1b0 [ 31.460900] memcpy+0x23/0x50 [ 31.464001] pdu_read+0x90/0xd0 [ 31.467283] p9pdu_readf+0x579/0x2170 [ 31.471068] ? p9pdu_writef+0xe0/0xe0 [ 31.475663] ? __fget+0x414/0x670 [ 31.479104] ? rcu_is_watching+0x61/0x150 [ 31.483235] ? expand_files.part.8+0x9c0/0x9c0 [ 31.487813] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.492837] ? p9_fd_show_options+0x1c0/0x1c0 [ 31.497328] p9_client_create+0xde0/0x16c9 [ 31.501548] ? p9_client_read+0xc60/0xc60 [ 31.505679] ? find_held_lock+0x36/0x1c0 [ 31.509729] ? __lockdep_init_map+0x105/0x590 [ 31.514220] ? kasan_check_write+0x14/0x20 [ 31.518438] ? __init_rwsem+0x1cc/0x2a0 [ 31.522396] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 31.527394] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.532402] ? __kmalloc_track_caller+0x5f5/0x760 [ 31.537244] ? save_stack+0xa9/0xd0 [ 31.540858] ? save_stack+0x43/0xd0 [ 31.544474] ? kasan_kmalloc+0xc4/0xe0 [ 31.548361] ? kmem_cache_alloc_trace+0x152/0x780 [ 31.553226] ? memcpy+0x45/0x50 [ 31.556493] v9fs_session_init+0x21a/0x1a80 [ 31.560822] ? find_held_lock+0x36/0x1c0 [ 31.564872] ? v9fs_show_options+0x7e0/0x7e0 [ 31.569274] ? kasan_check_read+0x11/0x20 [ 31.573510] ? rcu_is_watching+0x8c/0x150 [ 31.577650] ? rcu_pm_notify+0xc0/0xc0 [ 31.581544] ? v9fs_mount+0x61/0x900 [ 31.585254] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.590256] ? kmem_cache_alloc_trace+0x616/0x780 [ 31.595085] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 31.600603] v9fs_mount+0x7c/0x900 [ 31.604130] mount_fs+0xae/0x328 [ 31.607485] vfs_kern_mount.part.34+0xdc/0x4e0 [ 31.612074] ? may_umount+0xb0/0xb0 [ 31.615685] ? _raw_read_unlock+0x22/0x30 [ 31.619824] ? __get_fs_type+0x97/0xc0 [ 31.623707] do_mount+0x581/0x30e0 [ 31.627235] ? copy_mount_string+0x40/0x40 [ 31.631457] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.636203] ? retint_kernel+0x10/0x10 [ 31.640092] ? copy_mount_options+0x213/0x380 [ 31.644580] ? write_comp_data+0x70/0x70 [ 31.648630] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.654154] ? copy_mount_options+0x285/0x380 [ 31.658639] ksys_mount+0x12d/0x140 [ 31.662272] __x64_sys_mount+0xbe/0x150 [ 31.666234] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.671262] do_syscall_64+0x1b9/0x820 [ 31.675137] ? syscall_return_slowpath+0x5e0/0x5e0 [ 31.680061] ? syscall_return_slowpath+0x31d/0x5e0 [ 31.684987] ? entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 31.690347] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.695179] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.700351] RIP: 0033:0x4401a9 [ 31.703514] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 31.722640] RSP: 002b:00007ffc5202d528 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 31.730348] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 00000000004401a9 [ 31.737621] RDX: 0000000020000140 RSI: 0000000020000100 RDI: 0000000000000000 [ 31.744876] RBP: 0030656c69662f2e R08: 00000000200002c0 R09: 0000000000000001 [ 31.752127] R10: 0000000000000000 R11: 0000000000000206 R12: 64663d736e617274 [ 31.759387] R13: 0000040000000002 R14: 0000000000000000 R15: 0000000000000000 [ 31.767187] Dumping ftrace buffer: [ 31.770720] (ftrace buffer empty) [ 31.774424] Kernel Offset: disabled [ 31.778039] Rebooting in 86400 seconds..