[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.379290] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 16.790889] random: sshd: uninitialized urandom read (32 bytes read) [ 16.990834] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.741123] random: sshd: uninitialized urandom read (32 bytes read) [ 31.084291] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.205' (ECDSA) to the list of known hosts. [ 36.523526] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 36.614908] ================================================================== [ 36.622317] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 36.628618] Read of size 38416 at addr ffff8801c8748bed by task syz-executor523/4459 [ 36.636525] [ 36.638221] CPU: 0 PID: 4459 Comm: syz-executor523 Not tainted 4.18.0-rc5-next-20180720+ #12 [ 36.646773] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.656105] Call Trace: [ 36.658677] dump_stack+0x1c9/0x2b4 [ 36.662285] ? dump_stack_print_info.cold.2+0x52/0x52 [ 36.667465] ? printk+0xa7/0xcf [ 36.670725] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 36.675560] ? pdu_read+0x90/0xd0 [ 36.678995] print_address_description+0x6c/0x20b [ 36.683956] ? pdu_read+0x90/0xd0 [ 36.687413] kasan_report.cold.7+0x242/0x30d [ 36.691808] check_memory_region+0x13e/0x1b0 [ 36.696208] memcpy+0x23/0x50 [ 36.699303] pdu_read+0x90/0xd0 [ 36.702574] p9pdu_readf+0x579/0x2170 [ 36.706359] ? p9pdu_writef+0xe0/0xe0 [ 36.710141] ? ksys_dup3+0x690/0x690 [ 36.714182] ? check_same_owner+0x340/0x340 [ 36.718577] ? p9_fd_poll+0x2b0/0x2b0 [ 36.722363] ? kasan_kmalloc+0xc4/0xe0 [ 36.726448] ? p9_fd_show_options+0x1c0/0x1c0 [ 36.730961] p9_client_create+0x6d0/0x1537 [ 36.735197] ? p9_client_read+0xbb0/0xbb0 [ 36.739342] ? lock_acquire+0x1e4/0x540 [ 36.743403] ? fs_reclaim_acquire+0x20/0x20 [ 36.747715] ? lock_release+0xa30/0xa30 [ 36.751700] ? __lockdep_init_map+0x105/0x590 [ 36.756195] ? kasan_check_write+0x14/0x20 [ 36.760429] ? __init_rwsem+0x1cc/0x2a0 [ 36.764413] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 36.769442] ? __kmalloc_track_caller+0x311/0x760 [ 36.774286] ? save_stack+0xa9/0xd0 [ 36.777909] ? save_stack+0x43/0xd0 [ 36.781533] ? kasan_kmalloc+0xc4/0xe0 [ 36.785421] ? memcpy+0x45/0x50 [ 36.788694] v9fs_session_init+0x21a/0x1a80 [ 36.793000] ? rcu_note_context_switch+0x730/0x730 [ 36.798066] ? cache_grow_end.part.37+0x95/0x170 [ 36.802831] ? lock_downgrade+0x8f0/0x8f0 [ 36.806978] ? v9fs_show_options+0x7e0/0x7e0 [ 36.811388] ? kasan_check_read+0x11/0x20 [ 36.815741] ? do_raw_spin_unlock+0xa7/0x2f0 [ 36.820157] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 36.824747] ? kasan_check_write+0x14/0x20 [ 36.828987] ? do_raw_spin_lock+0xc1/0x200 [ 36.833239] ? kasan_unpoison_shadow+0x35/0x50 [ 36.837825] ? kasan_kmalloc+0xc4/0xe0 [ 36.852958] ? kmem_cache_alloc_trace+0x318/0x780 [ 36.857826] ? kasan_unpoison_shadow+0x35/0x50 [ 36.862515] ? kasan_kmalloc+0xc4/0xe0 [ 36.866424] v9fs_mount+0x7c/0x900 [ 36.869978] ? v9fs_drop_inode+0x150/0x150 [ 36.874234] legacy_get_tree+0x131/0x460 [ 36.878394] vfs_get_tree+0x1cb/0x5c0 [ 36.882308] do_mount+0x6f2/0x1e20 [ 36.885855] ? copy_mount_string+0x40/0x40 [ 36.890089] ? kasan_kmalloc+0xc4/0xe0 [ 36.894066] ? kmem_cache_alloc_trace+0x318/0x780 [ 36.898919] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 36.904488] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 36.910057] ? copy_mount_options+0x285/0x380 [ 36.914568] ksys_mount+0x12d/0x140 [ 36.918304] __x64_sys_mount+0xbe/0x150 [ 36.922301] do_syscall_64+0x1b9/0x820 [ 36.926215] ? syscall_return_slowpath+0x5e0/0x5e0 [ 36.931158] ? syscall_return_slowpath+0x31d/0x5e0 [ 36.936099] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 36.941138] ? prepare_exit_to_usermode+0x291/0x3b0 [ 36.946161] ? perf_trace_sys_enter+0xb10/0xb10 [ 36.950837] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 36.955698] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 36.960895] RIP: 0033:0x4401a9 [ 36.964265] 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 [ 36.983456] RSP: 002b:00007fff973837d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 36.991168] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00000000004401a9 [ 36.998614] RDX: 0000000020000900 RSI: 0000000020000000 RDI: 0000000000000000 [ 37.005888] RBP: 613d737365636361 R08: 0000000020000380 R09: 0000000000000001 [ 37.013163] R10: 0000000000000000 R11: 0000000000000206 R12: 6f6c3d6568636163 [ 37.020434] R13: 64663d736e617274 R14: 0000000000000000 R15: 0000000000000000 [ 37.027715] [ 37.029353] Allocated by task 4459: [ 37.033018] save_stack+0x43/0xd0 [ 37.037181] kasan_kmalloc+0xc4/0xe0 [ 37.040912] __kmalloc+0x14e/0x760 [ 37.044469] p9_fcall_alloc+0x1e/0x90 [ 37.048285] p9_client_prepare_req.part.8+0x132/0xa00 [ 37.053509] p9_client_rpc+0x242/0x1330 [ 37.057491] p9_client_create+0xca4/0x1537 [ 37.061737] v9fs_session_init+0x21a/0x1a80 [ 37.066093] v9fs_mount+0x7c/0x900 [ 37.069654] legacy_get_tree+0x131/0x460 [ 37.073726] vfs_get_tree+0x1cb/0x5c0 [ 37.077561] do_mount+0x6f2/0x1e20 [ 37.081118] ksys_mount+0x12d/0x140 [ 37.084758] __x64_sys_mount+0xbe/0x150 [ 37.088754] do_syscall_64+0x1b9/0x820 [ 37.092656] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.097851] [ 37.099478] Freed by task 0: [ 37.102486] (stack is not available) [ 37.106205] [ 37.107858] The buggy address belongs to the object at ffff8801c8748bc0 [ 37.107858] which belongs to the cache kmalloc-16384 of size 16384 [ 37.120894] The buggy address is located 45 bytes inside of [ 37.120894] 16384-byte region [ffff8801c8748bc0, ffff8801c874cbc0) [ 37.132853] The buggy address belongs to the page: [ 37.137786] page:ffffea000721d200 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 37.147836] flags: 0x2fffc0000010200(slab|head) [ 37.152513] raw: 02fffc0000010200 ffffea0007171008 ffff8801da801c48 ffff8801da802200 [ 37.160533] raw: 0000000000000000 ffff8801c8748bc0 0000000100000001 0000000000000000 [ 37.169196] page dumped because: kasan: bad access detected [ 37.174911] [ 37.176538] Memory state around the buggy address: [ 37.181471] ffff8801c874aa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.188861] ffff8801c874ab00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.196243] >ffff8801c874ab80: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 37.203601] ^ [ 37.210095] ffff8801c874ac00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 37.217458] ffff8801c874ac80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 37.224820] ================================================================== [ 37.232299] Kernel panic - not syncing: panic_on_warn set ... [ 37.232299] [ 37.239687] CPU: 0 PID: 4459 Comm: syz-executor523 Tainted: G B 4.18.0-rc5-next-20180720+ #12 [ 37.249739] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.259110] Call Trace: [ 37.261709] dump_stack+0x1c9/0x2b4 [ 37.265342] ? dump_stack_print_info.cold.2+0x52/0x52 [ 37.270578] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.275341] panic+0x238/0x4e7 [ 37.278550] ? add_taint.cold.5+0x16/0x16 [ 37.282703] ? do_raw_spin_unlock+0xa7/0x2f0 [ 37.287119] ? pdu_read+0x90/0xd0 [ 37.290585] kasan_end_report+0x47/0x4f [ 37.294571] kasan_report.cold.7+0x76/0x30d [ 37.298914] check_memory_region+0x13e/0x1b0 [ 37.303365] memcpy+0x23/0x50 [ 37.306499] pdu_read+0x90/0xd0 [ 37.309812] p9pdu_readf+0x579/0x2170 [ 37.313625] ? p9pdu_writef+0xe0/0xe0 [ 37.317435] ? ksys_dup3+0x690/0x690 [ 37.321159] ? check_same_owner+0x340/0x340 [ 37.325498] ? p9_fd_poll+0x2b0/0x2b0 [ 37.329318] ? kasan_kmalloc+0xc4/0xe0 [ 37.333225] ? p9_fd_show_options+0x1c0/0x1c0 [ 37.337732] p9_client_create+0x6d0/0x1537 [ 37.341977] ? p9_client_read+0xbb0/0xbb0 [ 37.346124] ? lock_acquire+0x1e4/0x540 [ 37.350099] ? fs_reclaim_acquire+0x20/0x20 [ 37.354430] ? lock_release+0xa30/0xa30 [ 37.358417] ? __lockdep_init_map+0x105/0x590 [ 37.362932] ? kasan_check_write+0x14/0x20 [ 37.367172] ? __init_rwsem+0x1cc/0x2a0 [ 37.371146] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 37.376163] ? __kmalloc_track_caller+0x311/0x760 [ 37.381003] ? save_stack+0xa9/0xd0 [ 37.384627] ? save_stack+0x43/0xd0 [ 37.388248] ? kasan_kmalloc+0xc4/0xe0 [ 37.392138] ? memcpy+0x45/0x50 [ 37.395427] v9fs_session_init+0x21a/0x1a80 [ 37.399753] ? rcu_note_context_switch+0x730/0x730 [ 37.404700] ? cache_grow_end.part.37+0x95/0x170 [ 37.409466] ? lock_downgrade+0x8f0/0x8f0 [ 37.413631] ? v9fs_show_options+0x7e0/0x7e0 [ 37.418050] ? kasan_check_read+0x11/0x20 [ 37.422220] ? do_raw_spin_unlock+0xa7/0x2f0 [ 37.426637] ? do_raw_spin_trylock+0x1c0/0x1c0 [ 37.431237] ? kasan_check_write+0x14/0x20 [ 37.435479] ? do_raw_spin_lock+0xc1/0x200 [ 37.439725] ? kasan_unpoison_shadow+0x35/0x50 [ 37.444332] ? kasan_kmalloc+0xc4/0xe0 [ 37.448246] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.453095] ? kasan_unpoison_shadow+0x35/0x50 [ 37.457673] ? kasan_kmalloc+0xc4/0xe0 [ 37.461565] v9fs_mount+0x7c/0x900 [ 37.465110] ? v9fs_drop_inode+0x150/0x150 [ 37.469350] legacy_get_tree+0x131/0x460 [ 37.473428] vfs_get_tree+0x1cb/0x5c0 [ 37.477264] do_mount+0x6f2/0x1e20 [ 37.480828] ? copy_mount_string+0x40/0x40 [ 37.485090] ? kasan_kmalloc+0xc4/0xe0 [ 37.489074] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.493947] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 37.499521] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.505082] ? copy_mount_options+0x285/0x380 [ 37.509582] ksys_mount+0x12d/0x140 [ 37.513220] __x64_sys_mount+0xbe/0x150 [ 37.517196] do_syscall_64+0x1b9/0x820 [ 37.521091] ? syscall_return_slowpath+0x5e0/0x5e0 [ 37.526037] ? syscall_return_slowpath+0x31d/0x5e0 [ 37.530973] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 37.535992] ? prepare_exit_to_usermode+0x291/0x3b0 [ 37.541011] ? perf_trace_sys_enter+0xb10/0xb10 [ 37.545691] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.550553] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.555745] RIP: 0033:0x4401a9 [ 37.558935] 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 [ 37.578098] RSP: 002b:00007fff973837d8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 37.585817] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00000000004401a9 [ 37.593090] RDX: 0000000020000900 RSI: 0000000020000000 RDI: 0000000000000000 [ 37.600820] RBP: 613d737365636361 R08: 0000000020000380 R09: 0000000000000001 [ 37.608092] R10: 0000000000000000 R11: 0000000000000206 R12: 6f6c3d6568636163 [ 37.615370] R13: 64663d736e617274 R14: 0000000000000000 R15: 0000000000000000 [ 37.623275] Dumping ftrace buffer: [ 37.626843] (ftrace buffer empty) [ 37.630567] Kernel Offset: disabled [ 37.634199] Rebooting in 86400 seconds..