[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.597603] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.403140] random: sshd: uninitialized urandom read (32 bytes read) [ 19.605161] random: sshd: uninitialized urandom read (32 bytes read) [ 20.313711] random: sshd: uninitialized urandom read (32 bytes read) [ 20.449088] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.6' (ECDSA) to the list of known hosts. [ 26.174751] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program [ 26.502099] ================================================================== [ 26.509489] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 26.515610] Read of size 31547 at addr ffff8801b6ad092d by task syz-executor234/4472 [ 26.523463] [ 26.525073] CPU: 0 PID: 4472 Comm: syz-executor234 Not tainted 4.18.0-rc5-next-20180720+ #12 [ 26.533621] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.542949] Call Trace: [ 26.545517] dump_stack+0x1c9/0x2b4 [ 26.549135] ? dump_stack_print_info.cold.2+0x52/0x52 [ 26.554313] ? printk+0xa7/0xcf [ 26.557581] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 26.562321] ? pdu_read+0x90/0xd0 [ 26.565767] print_address_description+0x6c/0x20b [ 26.570589] ? pdu_read+0x90/0xd0 [ 26.574023] kasan_report.cold.7+0x242/0x30d [ 26.578425] check_memory_region+0x13e/0x1b0 [ 26.582815] memcpy+0x23/0x50 [ 26.585904] pdu_read+0x90/0xd0 [ 26.589174] p9pdu_readf+0x579/0x2170 [ 26.592961] ? p9pdu_writef+0xe0/0xe0 [ 26.596751] ? ksys_dup3+0x690/0x690 [ 26.600494] ? check_same_owner+0x340/0x340 [ 26.604802] ? p9_fd_poll+0x2b0/0x2b0 [ 26.608586] ? finish_wait+0x430/0x430 [ 26.612468] ? p9_fd_show_options+0x1c0/0x1c0 [ 26.616949] p9_client_create+0x6d0/0x1537 [ 26.621179] ? p9_client_read+0xbb0/0xbb0 [ 26.625314] ? lock_acquire+0x1e4/0x540 [ 26.629268] ? fs_reclaim_acquire+0x20/0x20 [ 26.633575] ? lock_release+0xa30/0xa30 [ 26.637529] ? __lockdep_init_map+0x105/0x590 [ 26.642007] ? kasan_check_write+0x14/0x20 [ 26.646221] ? __init_rwsem+0x1cc/0x2a0 [ 26.650173] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 26.655178] ? __kmalloc_track_caller+0x311/0x760 [ 26.659994] ? save_stack+0xa9/0xd0 [ 26.663871] ? save_stack+0x43/0xd0 [ 26.667482] ? kasan_kmalloc+0xc4/0xe0 [ 26.671356] ? memcpy+0x45/0x50 [ 26.674687] v9fs_session_init+0x21a/0x1a80 [ 26.678992] ? rcu_note_context_switch+0x730/0x730 [ 26.683904] ? legacy_parse_monolithic+0xde/0x1e0 [ 26.688739] ? v9fs_show_options+0x7e0/0x7e0 [ 26.693134] ? lock_release+0xa30/0xa30 [ 26.697088] ? check_same_owner+0x340/0x340 [ 26.701390] ? lock_downgrade+0x8f0/0x8f0 [ 26.705518] ? kasan_unpoison_shadow+0x35/0x50 [ 26.710086] ? kasan_kmalloc+0xc4/0xe0 [ 26.713954] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.718777] ? kasan_unpoison_shadow+0x35/0x50 [ 26.723341] ? kasan_kmalloc+0xc4/0xe0 [ 26.727211] v9fs_mount+0x7c/0x900 [ 26.730731] ? v9fs_drop_inode+0x150/0x150 [ 26.734953] legacy_get_tree+0x131/0x460 [ 26.739005] vfs_get_tree+0x1cb/0x5c0 [ 26.742796] do_mount+0x6f2/0x1e20 [ 26.746364] ? check_same_owner+0x340/0x340 [ 26.750680] ? lock_release+0xa30/0xa30 [ 26.754636] ? copy_mount_string+0x40/0x40 [ 26.758850] ? kasan_kmalloc+0xc4/0xe0 [ 26.762720] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.767544] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 26.773071] ? _copy_from_user+0xdf/0x150 [ 26.777212] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.782742] ? copy_mount_options+0x285/0x380 [ 26.787227] ksys_mount+0x12d/0x140 [ 26.790839] __x64_sys_mount+0xbe/0x150 [ 26.794849] do_syscall_64+0x1b9/0x820 [ 26.798744] ? finish_task_switch+0x1d3/0x870 [ 26.803221] ? syscall_return_slowpath+0x5e0/0x5e0 [ 26.808131] ? syscall_return_slowpath+0x31d/0x5e0 [ 26.813039] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 26.818032] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.823674] ? prepare_exit_to_usermode+0x291/0x3b0 [ 26.828667] ? perf_trace_sys_enter+0xb10/0xb10 [ 26.833343] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.838164] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.843330] RIP: 0033:0x4461f9 [ 26.846523] Code: e8 dc bb 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 ab 0e fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 26.865637] RSP: 002b:00007efc6318ace8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 26.873325] RAX: ffffffffffffffda RBX: 00000000006dbc24 RCX: 00000000004461f9 [ 26.880575] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 26.887820] RBP: 00000000006dbc20 R08: 00000000200001c0 R09: 0000000000000000 [ 26.895064] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 26.902310] R13: 00007ffdf4a391bf R14: 00007efc6318b9c0 R15: 0000000000000001 [ 26.909661] [ 26.911296] Allocated by task 4472: [ 26.914905] save_stack+0x43/0xd0 [ 26.918427] kasan_kmalloc+0xc4/0xe0 [ 26.922115] __kmalloc+0x14e/0x760 [ 26.925635] p9_fcall_alloc+0x1e/0x90 [ 26.929415] p9_client_prepare_req.part.8+0x132/0xa00 [ 26.934580] p9_client_rpc+0x242/0x1330 [ 26.938548] p9_client_create+0xca4/0x1537 [ 26.942768] v9fs_session_init+0x21a/0x1a80 [ 26.947064] v9fs_mount+0x7c/0x900 [ 26.950582] legacy_get_tree+0x131/0x460 [ 26.954623] vfs_get_tree+0x1cb/0x5c0 [ 26.958399] do_mount+0x6f2/0x1e20 [ 26.961916] ksys_mount+0x12d/0x140 [ 26.965528] __x64_sys_mount+0xbe/0x150 [ 26.969479] do_syscall_64+0x1b9/0x820 [ 26.973346] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.978515] [ 26.980123] Freed by task 0: [ 26.983117] (stack is not available) [ 26.986815] [ 26.988425] The buggy address belongs to the object at ffff8801b6ad0900 [ 26.988425] which belongs to the cache kmalloc-16384 of size 16384 [ 27.001409] The buggy address is located 45 bytes inside of [ 27.001409] 16384-byte region [ffff8801b6ad0900, ffff8801b6ad4900) [ 27.013345] The buggy address belongs to the page: [ 27.018252] page:ffffea0006dab400 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 27.028205] flags: 0x2fffc0000010200(slab|head) [ 27.033302] raw: 02fffc0000010200 ffffea0006daa808 ffff8801da801c48 ffff8801da802200 [ 27.041163] raw: 0000000000000000 ffff8801b6ad0900 0000000100000001 0000000000000000 [ 27.049023] page dumped because: kasan: bad access detected [ 27.054705] [ 27.056316] Memory state around the buggy address: [ 27.061220] ffff8801b6ad2800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.068554] ffff8801b6ad2880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.075888] >ffff8801b6ad2900: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 27.083217] ^ [ 27.087598] ffff8801b6ad2980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.094931] ffff8801b6ad2a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.102260] ================================================================== [ 27.109650] Kernel panic - not syncing: panic_on_warn set ... [ 27.109650] [ 27.117005] CPU: 0 PID: 4472 Comm: syz-executor234 Tainted: G B 4.18.0-rc5-next-20180720+ #12 [ 27.126951] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.136288] Call Trace: [ 27.138865] dump_stack+0x1c9/0x2b4 [ 27.142472] ? dump_stack_print_info.cold.2+0x52/0x52 [ 27.147643] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.152378] panic+0x238/0x4e7 [ 27.155561] ? add_taint.cold.5+0x16/0x16 [ 27.159701] ? do_raw_spin_unlock+0xa7/0x2f0 [ 27.164099] ? pdu_read+0x90/0xd0 [ 27.167540] kasan_end_report+0x47/0x4f [ 27.171498] kasan_report.cold.7+0x76/0x30d [ 27.175799] check_memory_region+0x13e/0x1b0 [ 27.180216] memcpy+0x23/0x50 [ 27.183313] pdu_read+0x90/0xd0 [ 27.186598] p9pdu_readf+0x579/0x2170 [ 27.190376] ? p9pdu_writef+0xe0/0xe0 [ 27.194154] ? ksys_dup3+0x690/0x690 [ 27.197847] ? check_same_owner+0x340/0x340 [ 27.202145] ? p9_fd_poll+0x2b0/0x2b0 [ 27.205924] ? finish_wait+0x430/0x430 [ 27.209794] ? p9_fd_show_options+0x1c0/0x1c0 [ 27.214282] p9_client_create+0x6d0/0x1537 [ 27.218502] ? p9_client_read+0xbb0/0xbb0 [ 27.222627] ? lock_acquire+0x1e4/0x540 [ 27.226579] ? fs_reclaim_acquire+0x20/0x20 [ 27.230884] ? lock_release+0xa30/0xa30 [ 27.234843] ? __lockdep_init_map+0x105/0x590 [ 27.239318] ? kasan_check_write+0x14/0x20 [ 27.243529] ? __init_rwsem+0x1cc/0x2a0 [ 27.247482] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 27.252476] ? __kmalloc_track_caller+0x311/0x760 [ 27.257295] ? save_stack+0xa9/0xd0 [ 27.260896] ? save_stack+0x43/0xd0 [ 27.264496] ? kasan_kmalloc+0xc4/0xe0 [ 27.268356] ? memcpy+0x45/0x50 [ 27.271614] v9fs_session_init+0x21a/0x1a80 [ 27.275911] ? rcu_note_context_switch+0x730/0x730 [ 27.280815] ? legacy_parse_monolithic+0xde/0x1e0 [ 27.285637] ? v9fs_show_options+0x7e0/0x7e0 [ 27.290022] ? lock_release+0xa30/0xa30 [ 27.293972] ? check_same_owner+0x340/0x340 [ 27.298277] ? lock_downgrade+0x8f0/0x8f0 [ 27.302398] ? kasan_unpoison_shadow+0x35/0x50 [ 27.306955] ? kasan_kmalloc+0xc4/0xe0 [ 27.310828] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.315644] ? kasan_unpoison_shadow+0x35/0x50 [ 27.320202] ? kasan_kmalloc+0xc4/0xe0 [ 27.324070] v9fs_mount+0x7c/0x900 [ 27.327587] ? v9fs_drop_inode+0x150/0x150 [ 27.331798] legacy_get_tree+0x131/0x460 [ 27.335837] vfs_get_tree+0x1cb/0x5c0 [ 27.339627] do_mount+0x6f2/0x1e20 [ 27.343151] ? check_same_owner+0x340/0x340 [ 27.347449] ? lock_release+0xa30/0xa30 [ 27.351408] ? copy_mount_string+0x40/0x40 [ 27.355618] ? kasan_kmalloc+0xc4/0xe0 [ 27.359484] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.364303] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 27.369817] ? _copy_from_user+0xdf/0x150 [ 27.373943] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.379471] ? copy_mount_options+0x285/0x380 [ 27.383941] ksys_mount+0x12d/0x140 [ 27.387545] __x64_sys_mount+0xbe/0x150 [ 27.391498] do_syscall_64+0x1b9/0x820 [ 27.395358] ? finish_task_switch+0x1d3/0x870 [ 27.399834] ? syscall_return_slowpath+0x5e0/0x5e0 [ 27.404741] ? syscall_return_slowpath+0x31d/0x5e0 [ 27.409646] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 27.414643] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.420566] ? prepare_exit_to_usermode+0x291/0x3b0 [ 27.425560] ? perf_trace_sys_enter+0xb10/0xb10 [ 27.430210] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.435032] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.440227] RIP: 0033:0x4461f9 [ 27.443401] Code: e8 dc bb 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 ab 0e fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 27.462521] RSP: 002b:00007efc6318ace8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 27.470207] RAX: ffffffffffffffda RBX: 00000000006dbc24 RCX: 00000000004461f9 [ 27.477453] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 27.484709] RBP: 00000000006dbc20 R08: 00000000200001c0 R09: 0000000000000000 [ 27.491955] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 27.499203] R13: 00007ffdf4a391bf R14: 00007efc6318b9c0 R15: 0000000000000001 [ 27.507082] Dumping ftrace buffer: [ 27.510600] (ftrace buffer empty) [ 27.514287] Kernel Offset: disabled [ 27.517890] Rebooting in 86400 seconds..