[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.785935] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. [ 17.840313] random: sshd: uninitialized urandom read (32 bytes read) Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.092410] random: sshd: uninitialized urandom read (32 bytes read) [ 18.822512] random: sshd: uninitialized urandom read (32 bytes read) [ 18.960552] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.30' (ECDSA) to the list of known hosts. [ 24.360355] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program [ 24.448240] ================================================================== [ 24.455716] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 24.461856] Read of size 26417 at addr ffff8801b58984ad by task syz-executor831/4481 [ 24.469740] [ 24.471373] CPU: 0 PID: 4481 Comm: syz-executor831 Not tainted 4.18.0-rc3-next-20180706+ #1 [ 24.479852] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.489189] Call Trace: [ 24.492532] dump_stack+0x1c9/0x2b4 [ 24.496168] ? dump_stack_print_info.cold.2+0x52/0x52 [ 24.501350] ? printk+0xa7/0xcf [ 24.504624] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 24.509381] ? pdu_read+0x90/0xd0 [ 24.512821] print_address_description+0x6c/0x20b [ 24.517657] ? pdu_read+0x90/0xd0 [ 24.521112] kasan_report.cold.7+0x242/0x30d [ 24.525510] check_memory_region+0x13e/0x1b0 [ 24.529917] memcpy+0x23/0x50 [ 24.533008] pdu_read+0x90/0xd0 [ 24.536275] p9pdu_readf+0x579/0x2170 [ 24.540066] ? p9pdu_writef+0xe0/0xe0 [ 24.543853] ? ksys_dup3+0x690/0x690 [ 24.547553] ? check_same_owner+0x340/0x340 [ 24.551871] ? p9_fd_poll+0x2b0/0x2b0 [ 24.555679] ? kasan_kmalloc+0xc4/0xe0 [ 24.559591] ? kasan_unpoison_shadow+0x35/0x50 [ 24.564190] ? p9_fd_show_options+0x1c0/0x1c0 [ 24.568695] ? __raw_spin_lock_init+0x2d/0x100 [ 24.573276] p9_client_create+0xde0/0x16c9 [ 24.577507] ? p9_client_read+0xc60/0xc60 [ 24.581668] ? kasan_check_read+0x11/0x20 [ 24.585976] ? lock_acquire+0x1e4/0x540 [ 24.589994] ? fs_reclaim_acquire+0x20/0x20 [ 24.594346] ? lock_release+0xa30/0xa30 [ 24.598333] ? __lockdep_init_map+0x105/0x590 [ 24.602823] ? kasan_check_write+0x14/0x20 [ 24.607056] ? __init_rwsem+0x1cc/0x2a0 [ 24.611019] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 24.616056] ? __kmalloc_track_caller+0x311/0x760 [ 24.620897] ? save_stack+0xa9/0xd0 [ 24.624511] ? save_stack+0x43/0xd0 [ 24.628123] ? kasan_kmalloc+0xc4/0xe0 [ 24.632001] ? kmem_cache_alloc_trace+0x152/0x780 [ 24.636846] ? memcpy+0x45/0x50 [ 24.640130] v9fs_session_init+0x21a/0x1a80 [ 24.644453] ? rcu_note_context_switch+0x730/0x730 [ 24.649392] ? do_mount+0x69e/0x1fb0 [ 24.653105] ? lock_acquire+0x1e4/0x540 [ 24.657068] ? v9fs_show_options+0x7e0/0x7e0 [ 24.661481] ? lock_release+0xa30/0xa30 [ 24.665456] ? check_same_owner+0x340/0x340 [ 24.669767] ? kasan_unpoison_shadow+0x35/0x50 [ 24.674356] ? kasan_kmalloc+0xc4/0xe0 [ 24.678241] ? kmem_cache_alloc_trace+0x318/0x780 [ 24.683074] ? kasan_unpoison_shadow+0x35/0x50 [ 24.687649] ? kasan_kmalloc+0xc4/0xe0 [ 24.691524] v9fs_mount+0x7c/0x900 [ 24.695052] ? v9fs_drop_inode+0x150/0x150 [ 24.699271] legacy_get_tree+0x118/0x440 [ 24.703333] vfs_get_tree+0x1cb/0x5c0 [ 24.707145] do_mount+0x6c1/0x1fb0 [ 24.710675] ? check_same_owner+0x340/0x340 [ 24.714981] ? lock_release+0xa30/0xa30 [ 24.718941] ? copy_mount_string+0x40/0x40 [ 24.723166] ? kasan_kmalloc+0xc4/0xe0 [ 24.727050] ? kmem_cache_alloc_trace+0x318/0x780 [ 24.731887] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 24.737425] ? _copy_from_user+0xdf/0x150 [ 24.741578] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 24.747566] ? copy_mount_options+0x285/0x380 [ 24.752081] ksys_mount+0x12d/0x140 [ 24.755719] __x64_sys_mount+0xbe/0x150 [ 24.759702] do_syscall_64+0x1b9/0x820 [ 24.763579] ? syscall_return_slowpath+0x5e0/0x5e0 [ 24.768502] ? syscall_return_slowpath+0x31d/0x5e0 [ 24.773425] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 24.778459] ? prepare_exit_to_usermode+0x291/0x3b0 [ 24.783484] ? perf_trace_sys_enter+0xb10/0xb10 [ 24.788164] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 24.793036] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 24.798233] RIP: 0033:0x440109 [ 24.801405] 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 [ 24.820555] RSP: 002b:00007ffef8474fa8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 24.828396] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440109 [ 24.835676] RDX: 0000000020000080 RSI: 0000000020000000 RDI: 0000000000000000 [ 24.842939] RBP: 0030656c69662f2e R08: 0000000020000380 R09: 00000000004002c8 [ 24.850201] R10: 0000000000000000 R11: 0000000000000202 R12: 64663d736e617274 [ 24.857458] R13: 0000000000401a20 R14: 0000000000000000 R15: 0000000000000000 [ 24.864724] [ 24.866336] Allocated by task 4481: [ 24.869956] save_stack+0x43/0xd0 [ 24.873414] kasan_kmalloc+0xc4/0xe0 [ 24.877122] __kmalloc+0x14e/0x760 [ 24.880650] p9_fcall_alloc+0x1e/0x90 [ 24.884439] p9_client_prepare_req.part.9+0x754/0xcd0 [ 24.889616] p9_client_rpc+0x1bd/0x1400 [ 24.893576] p9_client_create+0xd09/0x16c9 [ 24.897800] v9fs_session_init+0x21a/0x1a80 [ 24.902107] v9fs_mount+0x7c/0x900 [ 24.905641] legacy_get_tree+0x118/0x440 [ 24.909701] vfs_get_tree+0x1cb/0x5c0 [ 24.913512] do_mount+0x6c1/0x1fb0 [ 24.917054] ksys_mount+0x12d/0x140 [ 24.920683] __x64_sys_mount+0xbe/0x150 [ 24.924650] do_syscall_64+0x1b9/0x820 [ 24.928527] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 24.933700] [ 24.935309] Freed by task 0: [ 24.938302] (stack is not available) [ 24.941995] [ 24.943612] The buggy address belongs to the object at ffff8801b5898480 [ 24.943612] which belongs to the cache kmalloc-16384 of size 16384 [ 24.956604] The buggy address is located 45 bytes inside of [ 24.956604] 16384-byte region [ffff8801b5898480, ffff8801b589c480) [ 24.968549] The buggy address belongs to the page: [ 24.973478] page:ffffea0006d62600 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 24.983448] flags: 0x2fffc0000008100(slab|head) [ 24.988121] raw: 02fffc0000008100 ffffea0006af9c08 ffff8801da801c48 ffff8801da802200 [ 24.996000] raw: 0000000000000000 ffff8801b5898480 0000000100000001 0000000000000000 [ 25.003868] page dumped because: kasan: bad access detected [ 25.009567] [ 25.011179] Memory state around the buggy address: [ 25.016284] ffff8801b589a380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 25.023638] ffff8801b589a400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 25.031003] >ffff8801b589a480: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 25.038356] ^ [ 25.042753] ffff8801b589a500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.050102] ffff8801b589a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.057447] ================================================================== [ 25.064894] Kernel panic - not syncing: panic_on_warn set ... [ 25.064894] [ 25.072274] CPU: 0 PID: 4481 Comm: syz-executor831 Tainted: G B 4.18.0-rc3-next-20180706+ #1 [ 25.082160] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.091515] Call Trace: [ 25.094125] dump_stack+0x1c9/0x2b4 [ 25.097755] ? dump_stack_print_info.cold.2+0x52/0x52 [ 25.102940] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.107690] panic+0x238/0x4e7 [ 25.110875] ? add_taint.cold.5+0x16/0x16 [ 25.115032] ? do_raw_spin_unlock+0xa7/0x2f0 [ 25.119450] ? pdu_read+0x90/0xd0 [ 25.122902] kasan_end_report+0x47/0x4f [ 25.126869] kasan_report.cold.7+0x76/0x30d [ 25.131188] check_memory_region+0x13e/0x1b0 [ 25.135601] memcpy+0x23/0x50 [ 25.138697] pdu_read+0x90/0xd0 [ 25.141968] p9pdu_readf+0x579/0x2170 [ 25.145768] ? p9pdu_writef+0xe0/0xe0 [ 25.149579] ? ksys_dup3+0x690/0x690 [ 25.153287] ? check_same_owner+0x340/0x340 [ 25.157599] ? p9_fd_poll+0x2b0/0x2b0 [ 25.161391] ? kasan_kmalloc+0xc4/0xe0 [ 25.165292] ? kasan_unpoison_shadow+0x35/0x50 [ 25.169886] ? p9_fd_show_options+0x1c0/0x1c0 [ 25.174389] ? __raw_spin_lock_init+0x2d/0x100 [ 25.178990] p9_client_create+0xde0/0x16c9 [ 25.183327] ? p9_client_read+0xc60/0xc60 [ 25.187475] ? kasan_check_read+0x11/0x20 [ 25.191620] ? lock_acquire+0x1e4/0x540 [ 25.195596] ? fs_reclaim_acquire+0x20/0x20 [ 25.199912] ? lock_release+0xa30/0xa30 [ 25.203880] ? __lockdep_init_map+0x105/0x590 [ 25.208374] ? kasan_check_write+0x14/0x20 [ 25.212599] ? __init_rwsem+0x1cc/0x2a0 [ 25.216569] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 25.221595] ? __kmalloc_track_caller+0x311/0x760 [ 25.226448] ? save_stack+0xa9/0xd0 [ 25.230077] ? save_stack+0x43/0xd0 [ 25.233720] ? kasan_kmalloc+0xc4/0xe0 [ 25.237615] ? kmem_cache_alloc_trace+0x152/0x780 [ 25.242474] ? memcpy+0x45/0x50 [ 25.245751] v9fs_session_init+0x21a/0x1a80 [ 25.250068] ? rcu_note_context_switch+0x730/0x730 [ 25.255014] ? do_mount+0x69e/0x1fb0 [ 25.258730] ? lock_acquire+0x1e4/0x540 [ 25.262703] ? v9fs_show_options+0x7e0/0x7e0 [ 25.267118] ? lock_release+0xa30/0xa30 [ 25.271088] ? check_same_owner+0x340/0x340 [ 25.275429] ? kasan_unpoison_shadow+0x35/0x50 [ 25.280008] ? kasan_kmalloc+0xc4/0xe0 [ 25.283896] ? kmem_cache_alloc_trace+0x318/0x780 [ 25.288739] ? kasan_unpoison_shadow+0x35/0x50 [ 25.293308] ? kasan_kmalloc+0xc4/0xe0 [ 25.297279] v9fs_mount+0x7c/0x900 [ 25.300810] ? v9fs_drop_inode+0x150/0x150 [ 25.305041] legacy_get_tree+0x118/0x440 [ 25.309106] vfs_get_tree+0x1cb/0x5c0 [ 25.312901] do_mount+0x6c1/0x1fb0 [ 25.316433] ? check_same_owner+0x340/0x340 [ 25.320743] ? lock_release+0xa30/0xa30 [ 25.324752] ? copy_mount_string+0x40/0x40 [ 25.329013] ? kasan_kmalloc+0xc4/0xe0 [ 25.332900] ? kmem_cache_alloc_trace+0x318/0x780 [ 25.337739] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 25.343290] ? _copy_from_user+0xdf/0x150 [ 25.347448] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 25.352982] ? copy_mount_options+0x285/0x380 [ 25.357556] ksys_mount+0x12d/0x140 [ 25.361178] __x64_sys_mount+0xbe/0x150 [ 25.365156] do_syscall_64+0x1b9/0x820 [ 25.369309] ? syscall_return_slowpath+0x5e0/0x5e0 [ 25.374381] ? syscall_return_slowpath+0x31d/0x5e0 [ 25.379312] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 25.384336] ? prepare_exit_to_usermode+0x291/0x3b0 [ 25.389354] ? perf_trace_sys_enter+0xb10/0xb10 [ 25.394035] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.398896] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 25.404083] RIP: 0033:0x440109 [ 25.407254] 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 [ 25.426405] RSP: 002b:00007ffef8474fa8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 25.434199] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440109 [ 25.441470] RDX: 0000000020000080 RSI: 0000000020000000 RDI: 0000000000000000 [ 25.448734] RBP: 0030656c69662f2e R08: 0000000020000380 R09: 00000000004002c8 [ 25.455995] R10: 0000000000000000 R11: 0000000000000202 R12: 64663d736e617274 [ 25.463286] R13: 0000000000401a20 R14: 0000000000000000 R15: 0000000000000000 [ 25.471468] Dumping ftrace buffer: [ 25.475102] (ftrace buffer empty) [ 25.479011] Kernel Offset: disabled [ 25.482637] Rebooting in 86400 seconds..