[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.879169] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.433220] random: sshd: uninitialized urandom read (32 bytes read) [ 19.759441] random: sshd: uninitialized urandom read (32 bytes read) [ 20.500898] random: sshd: uninitialized urandom read (32 bytes read) [ 20.638129] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.49' (ECDSA) to the list of known hosts. [ 26.076878] 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 [ 26.678839] ================================================================== [ 26.686337] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 26.692461] Read of size 64043 at addr ffff8801b25b84ed by task syz-executor861/4474 [ 26.700311] [ 26.701927] CPU: 0 PID: 4474 Comm: syz-executor861 Not tainted 4.18.0-rc5-next-20180720+ #12 [ 26.710475] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.719801] Call Trace: [ 26.722369] dump_stack+0x1c9/0x2b4 [ 26.725980] ? dump_stack_print_info.cold.2+0x52/0x52 [ 26.731149] ? printk+0xa7/0xcf [ 26.734404] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 26.739146] ? pdu_read+0x90/0xd0 [ 26.742579] print_address_description+0x6c/0x20b [ 26.747512] ? pdu_read+0x90/0xd0 [ 26.750943] kasan_report.cold.7+0x242/0x30d [ 26.755339] check_memory_region+0x13e/0x1b0 [ 26.759722] memcpy+0x23/0x50 [ 26.762913] pdu_read+0x90/0xd0 [ 26.766168] p9pdu_readf+0x579/0x2170 [ 26.769946] ? p9pdu_writef+0xe0/0xe0 [ 26.773724] ? ksys_dup3+0x690/0x690 [ 26.777414] ? check_same_owner+0x340/0x340 [ 26.781710] ? p9_fd_poll+0x2b0/0x2b0 [ 26.785486] ? finish_wait+0x430/0x430 [ 26.789357] ? p9_fd_show_options+0x1c0/0x1c0 [ 26.793919] p9_client_create+0x6d0/0x1537 [ 26.798140] ? p9_client_read+0xbb0/0xbb0 [ 26.802263] ? lock_acquire+0x1e4/0x540 [ 26.806213] ? fs_reclaim_acquire+0x20/0x20 [ 26.810511] ? lock_release+0xa30/0xa30 [ 26.814461] ? __lockdep_init_map+0x105/0x590 [ 26.818935] ? kasan_check_write+0x14/0x20 [ 26.823145] ? __init_rwsem+0x1cc/0x2a0 [ 26.827094] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 26.832088] ? __kmalloc_track_caller+0x311/0x760 [ 26.836914] ? save_stack+0xa9/0xd0 [ 26.840518] ? save_stack+0x43/0xd0 [ 26.844117] ? kasan_kmalloc+0xc4/0xe0 [ 26.847978] ? memcpy+0x45/0x50 [ 26.851246] v9fs_session_init+0x21a/0x1a80 [ 26.855543] ? rcu_note_context_switch+0x730/0x730 [ 26.860451] ? legacy_parse_monolithic+0xde/0x1e0 [ 26.865456] ? v9fs_show_options+0x7e0/0x7e0 [ 26.869841] ? lock_release+0xa30/0xa30 [ 26.873791] ? check_same_owner+0x340/0x340 [ 26.878088] ? lock_downgrade+0x8f0/0x8f0 [ 26.882219] ? kasan_unpoison_shadow+0x35/0x50 [ 26.886778] ? kasan_kmalloc+0xc4/0xe0 [ 26.890640] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.895458] ? kasan_unpoison_shadow+0x35/0x50 [ 26.900019] ? kasan_kmalloc+0xc4/0xe0 [ 26.903902] v9fs_mount+0x7c/0x900 [ 26.907417] ? v9fs_drop_inode+0x150/0x150 [ 26.911630] legacy_get_tree+0x131/0x460 [ 26.915694] vfs_get_tree+0x1cb/0x5c0 [ 26.919481] do_mount+0x6f2/0x1e20 [ 26.923005] ? check_same_owner+0x340/0x340 [ 26.927396] ? lock_release+0xa30/0xa30 [ 26.931348] ? copy_mount_string+0x40/0x40 [ 26.935561] ? kasan_kmalloc+0xc4/0xe0 [ 26.939426] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.944247] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 26.949767] ? _copy_from_user+0xdf/0x150 [ 26.954232] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.959786] ? copy_mount_options+0x285/0x380 [ 26.964405] ksys_mount+0x12d/0x140 [ 26.968014] __x64_sys_mount+0xbe/0x150 [ 26.971966] do_syscall_64+0x1b9/0x820 [ 26.975831] ? syscall_return_slowpath+0x5e0/0x5e0 [ 26.980752] ? syscall_return_slowpath+0x31d/0x5e0 [ 26.985663] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 26.990663] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.996180] ? prepare_exit_to_usermode+0x291/0x3b0 [ 27.001184] ? perf_trace_sys_enter+0xb10/0xb10 [ 27.005834] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.010659] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.015826] RIP: 0033:0x4406a9 [ 27.018992] 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 0f fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 27.038128] RSP: 002b:00007ffc8ca7fe08 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 27.045812] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00000000004406a9 [ 27.053060] RDX: 00000000200000c0 RSI: 0000000020000000 RDI: 0000000000000000 [ 27.060305] RBP: 6f72746e6f632f2e R08: 00000000200004c0 R09: 00000000004002c8 [ 27.067552] R10: 0000000000000000 R11: 0000000000000202 R12: 7073642f7665642f [ 27.074803] R13: 0030656c69662f6c R14: 0000000000000000 R15: 0000000000000000 [ 27.082064] [ 27.083666] Allocated by task 4474: [ 27.087283] save_stack+0x43/0xd0 [ 27.090709] kasan_kmalloc+0xc4/0xe0 [ 27.094400] __kmalloc+0x14e/0x760 [ 27.097914] p9_fcall_alloc+0x1e/0x90 [ 27.101691] p9_client_prepare_req.part.8+0x132/0xa00 [ 27.106855] p9_client_rpc+0x242/0x1330 [ 27.110805] p9_client_create+0xca4/0x1537 [ 27.115025] v9fs_session_init+0x21a/0x1a80 [ 27.119325] v9fs_mount+0x7c/0x900 [ 27.122846] legacy_get_tree+0x131/0x460 [ 27.126896] vfs_get_tree+0x1cb/0x5c0 [ 27.130674] do_mount+0x6f2/0x1e20 [ 27.134190] ksys_mount+0x12d/0x140 [ 27.137793] __x64_sys_mount+0xbe/0x150 [ 27.141741] do_syscall_64+0x1b9/0x820 [ 27.145606] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.150768] [ 27.152374] Freed by task 0: [ 27.155368] (stack is not available) [ 27.159053] [ 27.160659] The buggy address belongs to the object at ffff8801b25b84c0 [ 27.160659] which belongs to the cache kmalloc-16384 of size 16384 [ 27.173639] The buggy address is located 45 bytes inside of executing program executing program executing program executing program [ 27.173639] 16384-byte region [ffff8801b25b84c0, ffff8801b25bc4c0) [ 27.185592] The buggy address belongs to the page: [ 27.190505] page:ffffea0006c96e00 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 27.200447] flags: 0x2fffc0000010200(slab|head) [ 27.205107] raw: 02fffc0000010200 ffffea0006b44e08 ffffea0006a19a08 ffff8801da802200 [ 27.212967] raw: 0000000000000000 ffff8801b25b84c0 0000000100000001 0000000000000000 [ 27.220818] page dumped because: kasan: bad access detected [ 27.226497] [ 27.228098] Memory state around the buggy address: [ 27.233002] ffff8801b25ba380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.240348] ffff8801b25ba400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.247687] >ffff8801b25ba480: 00 00 00 00 00 00 00 00 00 00 00 00 fc fc fc fc [ 27.255021] ^ [ 27.261492] ffff8801b25ba500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.268930] ffff8801b25ba580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.276264] ================================================================== [ 27.283733] Kernel panic - not syncing: panic_on_warn set ... [ 27.283733] [ 27.291087] CPU: 0 PID: 4474 Comm: syz-executor861 Tainted: G B 4.18.0-rc5-next-20180720+ #12 [ 27.301134] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.310478] Call Trace: [ 27.313052] dump_stack+0x1c9/0x2b4 [ 27.316660] ? dump_stack_print_info.cold.2+0x52/0x52 [ 27.321850] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.326588] panic+0x238/0x4e7 [ 27.329765] ? add_taint.cold.5+0x16/0x16 [ 27.333899] ? do_raw_spin_unlock+0xa7/0x2f0 [ 27.338291] ? pdu_read+0x90/0xd0 [ 27.341726] kasan_end_report+0x47/0x4f [ 27.345681] kasan_report.cold.7+0x76/0x30d [ 27.349985] check_memory_region+0x13e/0x1b0 [ 27.354382] memcpy+0x23/0x50 [ 27.357476] pdu_read+0x90/0xd0 [ 27.360740] p9pdu_readf+0x579/0x2170 [ 27.364524] ? p9pdu_writef+0xe0/0xe0 [ 27.368305] ? ksys_dup3+0x690/0x690 [ 27.371999] ? check_same_owner+0x340/0x340 [ 27.376297] ? p9_fd_poll+0x2b0/0x2b0 [ 27.380077] ? finish_wait+0x430/0x430 [ 27.383958] ? p9_fd_show_options+0x1c0/0x1c0 [ 27.388443] p9_client_create+0x6d0/0x1537 [ 27.392657] ? p9_client_read+0xbb0/0xbb0 [ 27.396787] ? lock_acquire+0x1e4/0x540 [ 27.400741] ? fs_reclaim_acquire+0x20/0x20 [ 27.405046] ? lock_release+0xa30/0xa30 [ 27.409004] ? __lockdep_init_map+0x105/0x590 [ 27.413490] ? kasan_check_write+0x14/0x20 [ 27.417704] ? __init_rwsem+0x1cc/0x2a0 [ 27.421659] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 27.426664] ? __kmalloc_track_caller+0x311/0x760 [ 27.431487] ? save_stack+0xa9/0xd0 [ 27.435092] ? save_stack+0x43/0xd0 [ 27.438697] ? kasan_kmalloc+0xc4/0xe0 [ 27.442565] ? memcpy+0x45/0x50 [ 27.445833] v9fs_session_init+0x21a/0x1a80 [ 27.450134] ? rcu_note_context_switch+0x730/0x730 [ 27.455043] ? legacy_parse_monolithic+0xde/0x1e0 [ 27.459866] ? v9fs_show_options+0x7e0/0x7e0 [ 27.464263] ? lock_release+0xa30/0xa30 [ 27.468245] ? check_same_owner+0x340/0x340 [ 27.472567] ? lock_downgrade+0x8f0/0x8f0 [ 27.476707] ? kasan_unpoison_shadow+0x35/0x50 [ 27.481268] ? kasan_kmalloc+0xc4/0xe0 [ 27.485141] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.489964] ? kasan_unpoison_shadow+0x35/0x50 [ 27.494526] ? kasan_kmalloc+0xc4/0xe0 [ 27.498397] v9fs_mount+0x7c/0x900 [ 27.501923] ? v9fs_drop_inode+0x150/0x150 [ 27.506151] legacy_get_tree+0x131/0x460 [ 27.510198] vfs_get_tree+0x1cb/0x5c0 [ 27.513985] do_mount+0x6f2/0x1e20 [ 27.517506] ? check_same_owner+0x340/0x340 [ 27.521810] ? lock_release+0xa30/0xa30 [ 27.525776] ? copy_mount_string+0x40/0x40 [ 27.529992] ? kasan_kmalloc+0xc4/0xe0 [ 27.533875] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.538709] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 27.544225] ? _copy_from_user+0xdf/0x150 [ 27.548362] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.553886] ? copy_mount_options+0x285/0x380 [ 27.558363] ksys_mount+0x12d/0x140 [ 27.561971] __x64_sys_mount+0xbe/0x150 [ 27.565929] do_syscall_64+0x1b9/0x820 [ 27.569797] ? syscall_return_slowpath+0x5e0/0x5e0 [ 27.574709] ? syscall_return_slowpath+0x31d/0x5e0 [ 27.579634] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 27.584635] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.590153] ? prepare_exit_to_usermode+0x291/0x3b0 [ 27.595147] ? perf_trace_sys_enter+0xb10/0xb10 [ 27.599793] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.604617] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.609792] RIP: 0033:0x4406a9 [ 27.612956] 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 0f fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 27.632077] RSP: 002b:00007ffc8ca7fe08 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 27.639768] RAX: ffffffffffffffda RBX: 0030656c69662f2e RCX: 00000000004406a9 [ 27.647021] RDX: 00000000200000c0 RSI: 0000000020000000 RDI: 0000000000000000 [ 27.654273] RBP: 6f72746e6f632f2e R08: 00000000200004c0 R09: 00000000004002c8 [ 27.661524] R10: 0000000000000000 R11: 0000000000000202 R12: 7073642f7665642f [ 27.668776] R13: 0030656c69662f6c R14: 0000000000000000 R15: 0000000000000000 [ 27.676408] Dumping ftrace buffer: [ 27.679931] (ftrace buffer empty) [ 27.683628] Kernel Offset: disabled [ 27.687238] Rebooting in 86400 seconds..