[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.472900] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.552137] random: sshd: uninitialized urandom read (32 bytes read) [ 21.060668] random: sshd: uninitialized urandom read (32 bytes read) [ 21.759713] random: sshd: uninitialized urandom read (32 bytes read) [ 39.985438] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.10.18' (ECDSA) to the list of known hosts. [ 45.368751] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program [ 45.623374] ================================================================== [ 45.630774] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 45.636909] Read of size 56015 at addr ffff8801b1ae07ad by task syz-executor904/4485 [ 45.644775] [ 45.646404] CPU: 0 PID: 4485 Comm: syz-executor904 Not tainted 4.18.0-rc5-next-20180720+ #12 [ 45.654966] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.664311] Call Trace: [ 45.666892] dump_stack+0x1c9/0x2b4 [ 45.670500] ? dump_stack_print_info.cold.2+0x52/0x52 [ 45.675677] ? printk+0xa7/0xcf [ 45.678947] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 45.683690] ? pdu_read+0x90/0xd0 [ 45.687127] print_address_description+0x6c/0x20b [ 45.691949] ? pdu_read+0x90/0xd0 [ 45.695483] kasan_report.cold.7+0x242/0x30d [ 45.699880] check_memory_region+0x13e/0x1b0 [ 45.704278] memcpy+0x23/0x50 [ 45.707373] pdu_read+0x90/0xd0 [ 45.710631] p9pdu_readf+0x579/0x2170 [ 45.714407] ? p9pdu_writef+0xe0/0xe0 [ 45.718186] ? ksys_dup3+0x690/0x690 [ 45.721881] ? check_same_owner+0x340/0x340 [ 45.726182] ? p9_fd_poll+0x2b0/0x2b0 [ 45.729973] ? finish_wait+0x430/0x430 [ 45.733845] ? p9_fd_show_options+0x1c0/0x1c0 [ 45.738323] p9_client_create+0x6d0/0x1537 [ 45.742549] ? p9_client_read+0xbb0/0xbb0 [ 45.746687] ? lock_acquire+0x1e4/0x540 [ 45.750651] ? fs_reclaim_acquire+0x20/0x20 [ 45.754965] ? lock_release+0xa30/0xa30 [ 45.758930] ? __lockdep_init_map+0x105/0x590 [ 45.763419] ? kasan_check_write+0x14/0x20 [ 45.767650] ? __init_rwsem+0x1cc/0x2a0 [ 45.771606] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 45.776605] ? __kmalloc_track_caller+0x311/0x760 [ 45.781427] ? save_stack+0xa9/0xd0 [ 45.785124] ? save_stack+0x43/0xd0 [ 45.788729] ? kasan_kmalloc+0xc4/0xe0 [ 45.792607] ? memcpy+0x45/0x50 [ 45.795873] v9fs_session_init+0x21a/0x1a80 [ 45.800179] ? rcu_note_context_switch+0x730/0x730 [ 45.805091] ? legacy_parse_monolithic+0xde/0x1e0 [ 45.809923] ? v9fs_show_options+0x7e0/0x7e0 [ 45.814316] ? lock_release+0xa30/0xa30 [ 45.818274] ? check_same_owner+0x340/0x340 [ 45.822590] ? lock_downgrade+0x8f0/0x8f0 [ 45.826738] ? kasan_unpoison_shadow+0x35/0x50 [ 45.831664] ? kasan_kmalloc+0xc4/0xe0 [ 45.835536] ? kmem_cache_alloc_trace+0x318/0x780 [ 45.840363] ? kasan_unpoison_shadow+0x35/0x50 [ 45.844920] ? kasan_kmalloc+0xc4/0xe0 [ 45.848791] v9fs_mount+0x7c/0x900 [ 45.852314] ? v9fs_drop_inode+0x150/0x150 [ 45.856533] legacy_get_tree+0x131/0x460 [ 45.860600] vfs_get_tree+0x1cb/0x5c0 [ 45.864383] do_mount+0x6f2/0x1e20 [ 45.867912] ? check_same_owner+0x340/0x340 [ 45.872357] ? lock_release+0xa30/0xa30 [ 45.876315] ? copy_mount_string+0x40/0x40 [ 45.880534] ? kasan_kmalloc+0xc4/0xe0 [ 45.884399] ? kmem_cache_alloc_trace+0x318/0x780 [ 45.889225] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 45.894744] ? _copy_from_user+0xdf/0x150 [ 45.898883] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.904406] ? copy_mount_options+0x285/0x380 [ 45.908882] ksys_mount+0x12d/0x140 [ 45.912491] __x64_sys_mount+0xbe/0x150 [ 45.916445] do_syscall_64+0x1b9/0x820 [ 45.920318] ? syscall_return_slowpath+0x5e0/0x5e0 [ 45.925232] ? syscall_return_slowpath+0x31d/0x5e0 [ 45.930141] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 45.935142] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 45.940665] ? prepare_exit_to_usermode+0x291/0x3b0 [ 45.945670] ? perf_trace_sys_enter+0xb10/0xb10 [ 45.950408] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.955238] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.960410] RIP: 0033:0x445f69 [ 45.963573] 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 [ 45.982704] RSP: 002b:00007f7a37048ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 45.990401] RAX: ffffffffffffffda RBX: 00000000006dbc44 RCX: 0000000000445f69 [ 45.997648] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 46.004895] RBP: 00000000006dbc40 R08: 0000000020000380 R09: 0000000000000000 [ 46.012143] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 46.019393] R13: 00007ffdf2c87b9f R14: 00007f7a370499c0 R15: 0000000000000001 [ 46.026678] [ 46.028283] Allocated by task 4485: [ 46.031895] save_stack+0x43/0xd0 [ 46.035331] kasan_kmalloc+0xc4/0xe0 [ 46.039037] __kmalloc+0x14e/0x760 [ 46.042563] p9_fcall_alloc+0x1e/0x90 [ 46.046357] p9_client_prepare_req.part.8+0x132/0xa00 [ 46.051532] p9_client_rpc+0x242/0x1330 [ 46.055549] p9_client_create+0xca4/0x1537 [ 46.059768] v9fs_session_init+0x21a/0x1a80 [ 46.064081] v9fs_mount+0x7c/0x900 [ 46.067613] legacy_get_tree+0x131/0x460 [ 46.071664] vfs_get_tree+0x1cb/0x5c0 [ 46.075458] do_mount+0x6f2/0x1e20 [ 46.080109] ksys_mount+0x12d/0x140 [ 46.083722] __x64_sys_mount+0xbe/0x150 [ 46.087678] do_syscall_64+0x1b9/0x820 [ 46.091545] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.096707] [ 46.098315] Freed by task 0: [ 46.101326] (stack is not available) [ 46.105018] [ 46.106625] The buggy address belongs to the object at ffff8801b1ae0780 [ 46.106625] which belongs to the cache kmalloc-16384 of size 16384 [ 46.119617] The buggy address is located 45 bytes inside of [ 46.119617] 16384-byte region [ffff8801b1ae0780, ffff8801b1ae4780) [ 46.131562] The buggy address belongs to the page: [ 46.136482] page:ffffea0006c6b800 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 46.146432] flags: 0x2fffc0000010200(slab|head) [ 46.151084] raw: 02fffc0000010200 ffffea0006d36008 ffff8801da801c48 ffff8801da802200 [ 46.158954] raw: 0000000000000000 ffff8801b1ae0780 0000000100000001 0000000000000000 [ 46.166897] page dumped because: kasan: bad access detected [ 46.172594] [ 46.174194] Memory state around the buggy address: [ 46.179106] ffff8801b1ae2680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 46.186449] ffff8801b1ae2700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 46.193787] >ffff8801b1ae2780: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 46.201153] ^ [ 46.205539] ffff8801b1ae2800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.212879] ffff8801b1ae2880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 46.220246] ================================================================== [ 46.227661] Kernel panic - not syncing: panic_on_warn set ... [ 46.227661] [ 46.235015] CPU: 0 PID: 4485 Comm: syz-executor904 Tainted: G B 4.18.0-rc5-next-20180720+ #12 [ 46.244968] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.254309] Call Trace: [ 46.256901] dump_stack+0x1c9/0x2b4 [ 46.260512] ? dump_stack_print_info.cold.2+0x52/0x52 [ 46.265684] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 46.270420] panic+0x238/0x4e7 [ 46.273594] ? add_taint.cold.5+0x16/0x16 [ 46.277818] ? do_raw_spin_unlock+0xa7/0x2f0 [ 46.282218] ? pdu_read+0x90/0xd0 [ 46.285655] kasan_end_report+0x47/0x4f [ 46.289616] kasan_report.cold.7+0x76/0x30d [ 46.293923] check_memory_region+0x13e/0x1b0 [ 46.298307] memcpy+0x23/0x50 [ 46.301392] pdu_read+0x90/0xd0 [ 46.304650] p9pdu_readf+0x579/0x2170 [ 46.308435] ? p9pdu_writef+0xe0/0xe0 [ 46.312213] ? ksys_dup3+0x690/0x690 [ 46.315902] ? check_same_owner+0x340/0x340 [ 46.320202] ? p9_fd_poll+0x2b0/0x2b0 [ 46.323982] ? finish_wait+0x430/0x430 [ 46.327868] ? p9_fd_show_options+0x1c0/0x1c0 [ 46.332345] p9_client_create+0x6d0/0x1537 [ 46.336575] ? p9_client_read+0xbb0/0xbb0 [ 46.342094] ? lock_acquire+0x1e4/0x540 [ 46.346063] ? fs_reclaim_acquire+0x20/0x20 [ 46.350388] ? lock_release+0xa30/0xa30 [ 46.354344] ? __lockdep_init_map+0x105/0x590 [ 46.358829] ? kasan_check_write+0x14/0x20 [ 46.363057] ? __init_rwsem+0x1cc/0x2a0 [ 46.367007] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 46.372087] ? __kmalloc_track_caller+0x311/0x760 [ 46.376903] ? save_stack+0xa9/0xd0 [ 46.380514] ? save_stack+0x43/0xd0 [ 46.384116] ? kasan_kmalloc+0xc4/0xe0 [ 46.387987] ? memcpy+0x45/0x50 [ 46.391358] v9fs_session_init+0x21a/0x1a80 [ 46.395662] ? rcu_note_context_switch+0x730/0x730 [ 46.400587] ? legacy_parse_monolithic+0xde/0x1e0 [ 46.405433] ? v9fs_show_options+0x7e0/0x7e0 [ 46.409828] ? lock_release+0xa30/0xa30 [ 46.413783] ? check_same_owner+0x340/0x340 [ 46.418082] ? lock_downgrade+0x8f0/0x8f0 [ 46.422219] ? kasan_unpoison_shadow+0x35/0x50 [ 46.426785] ? kasan_kmalloc+0xc4/0xe0 [ 46.430659] ? kmem_cache_alloc_trace+0x318/0x780 [ 46.435492] ? kasan_unpoison_shadow+0x35/0x50 [ 46.440071] ? kasan_kmalloc+0xc4/0xe0 [ 46.443948] v9fs_mount+0x7c/0x900 [ 46.447469] ? v9fs_drop_inode+0x150/0x150 [ 46.451678] legacy_get_tree+0x131/0x460 [ 46.455763] vfs_get_tree+0x1cb/0x5c0 [ 46.459544] do_mount+0x6f2/0x1e20 [ 46.463065] ? check_same_owner+0x340/0x340 [ 46.467379] ? lock_release+0xa30/0xa30 [ 46.471338] ? copy_mount_string+0x40/0x40 [ 46.475554] ? kasan_kmalloc+0xc4/0xe0 [ 46.479421] ? kmem_cache_alloc_trace+0x318/0x780 [ 46.484240] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 46.489755] ? _copy_from_user+0xdf/0x150 [ 46.493880] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 46.499403] ? copy_mount_options+0x285/0x380 [ 46.503890] ksys_mount+0x12d/0x140 [ 46.507511] __x64_sys_mount+0xbe/0x150 [ 46.511670] do_syscall_64+0x1b9/0x820 [ 46.515540] ? syscall_return_slowpath+0x5e0/0x5e0 [ 46.520489] ? syscall_return_slowpath+0x31d/0x5e0 [ 46.525396] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 46.530487] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 46.536009] ? prepare_exit_to_usermode+0x291/0x3b0 [ 46.541008] ? perf_trace_sys_enter+0xb10/0xb10 [ 46.545660] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 46.550521] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 46.555700] RIP: 0033:0x445f69 [ 46.558868] 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 [ 46.578082] RSP: 002b:00007f7a37048ce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 [ 46.585767] RAX: ffffffffffffffda RBX: 00000000006dbc44 RCX: 0000000000445f69 [ 46.593016] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 46.600261] RBP: 00000000006dbc40 R08: 0000000020000380 R09: 0000000000000000 [ 46.607521] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 46.614766] R13: 00007ffdf2c87b9f R14: 00007f7a370499c0 R15: 0000000000000001 [ 46.622570] Dumping ftrace buffer: [ 46.626089] (ftrace buffer empty) [ 46.629777] Kernel Offset: disabled [ 46.633386] Rebooting in 86400 seconds..