[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 15.913985] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.200297] random: sshd: uninitialized urandom read (32 bytes read) [ 19.453207] random: sshd: uninitialized urandom read (32 bytes read) [ 20.177498] random: sshd: uninitialized urandom read (32 bytes read) [ 20.312474] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.40' (ECDSA) to the list of known hosts. [ 25.717516] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program [ 25.801640] ================================================================== [ 25.809060] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 25.815222] Read of size 25368 at addr ffff8801d3d7862d by task syz-executor073/4461 [ 25.823078] [ 25.824715] CPU: 1 PID: 4461 Comm: syz-executor073 Not tainted 4.18.0-rc3-next-20180706+ #1 [ 25.833191] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.842524] Call Trace: [ 25.845102] dump_stack+0x1c9/0x2b4 [ 25.848814] ? dump_stack_print_info.cold.2+0x52/0x52 [ 25.854000] ? printk+0xa7/0xcf [ 25.857278] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 25.862038] ? pdu_read+0x90/0xd0 [ 25.865492] print_address_description+0x6c/0x20b [ 25.870321] ? pdu_read+0x90/0xd0 [ 25.873765] kasan_report.cold.7+0x242/0x30d [ 25.878156] check_memory_region+0x13e/0x1b0 [ 25.882546] memcpy+0x23/0x50 [ 25.885644] pdu_read+0x90/0xd0 [ 25.888917] p9pdu_readf+0x579/0x2170 [ 25.892699] ? p9pdu_writef+0xe0/0xe0 [ 25.896483] ? ksys_dup3+0x690/0x690 [ 25.900189] ? check_same_owner+0x340/0x340 [ 25.904489] ? p9_fd_poll+0x2b0/0x2b0 [ 25.908274] ? kasan_kmalloc+0xc4/0xe0 [ 25.912145] ? kasan_unpoison_shadow+0x35/0x50 [ 25.916708] ? p9_fd_show_options+0x1c0/0x1c0 [ 25.921185] ? __raw_spin_lock_init+0x2d/0x100 [ 25.925762] p9_client_create+0xde0/0x16c9 [ 25.929983] ? p9_client_read+0xc60/0xc60 [ 25.934116] ? kasan_check_read+0x11/0x20 [ 25.938262] ? lock_acquire+0x1e4/0x540 [ 25.942224] ? fs_reclaim_acquire+0x20/0x20 [ 25.946531] ? lock_release+0xa30/0xa30 [ 25.950487] ? __lockdep_init_map+0x105/0x590 [ 25.954970] ? kasan_check_write+0x14/0x20 [ 25.959184] ? __init_rwsem+0x1cc/0x2a0 [ 25.963141] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 25.968147] ? __kmalloc_track_caller+0x311/0x760 [ 25.972982] ? save_stack+0xa9/0xd0 [ 25.976591] ? save_stack+0x43/0xd0 [ 25.980197] ? kasan_kmalloc+0xc4/0xe0 [ 25.984068] ? kmem_cache_alloc_trace+0x152/0x780 [ 25.988892] ? memcpy+0x45/0x50 [ 25.992332] v9fs_session_init+0x21a/0x1a80 [ 25.996637] ? rcu_note_context_switch+0x730/0x730 [ 26.001548] ? do_mount+0x69e/0x1fb0 [ 26.005245] ? lock_acquire+0x1e4/0x540 [ 26.009201] ? v9fs_show_options+0x7e0/0x7e0 [ 26.013588] ? lock_release+0xa30/0xa30 [ 26.017542] ? check_same_owner+0x340/0x340 [ 26.021855] ? lock_downgrade+0x8f0/0x8f0 [ 26.025994] ? kasan_unpoison_shadow+0x35/0x50 [ 26.030560] ? kasan_kmalloc+0xc4/0xe0 [ 26.034427] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.039253] ? kasan_unpoison_shadow+0x35/0x50 [ 26.043815] ? kasan_kmalloc+0xc4/0xe0 [ 26.047684] v9fs_mount+0x7c/0x900 [ 26.051206] ? v9fs_drop_inode+0x150/0x150 [ 26.055438] legacy_get_tree+0x118/0x440 [ 26.059484] vfs_get_tree+0x1cb/0x5c0 [ 26.063273] do_mount+0x6c1/0x1fb0 [ 26.066808] ? check_same_owner+0x340/0x340 [ 26.071121] ? lock_release+0xa30/0xa30 [ 26.075077] ? copy_mount_string+0x40/0x40 [ 26.079304] ? kasan_kmalloc+0xc4/0xe0 [ 26.083192] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.088029] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 26.093578] ? _copy_from_user+0xdf/0x150 [ 26.097741] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.103310] ? copy_mount_options+0x285/0x380 [ 26.107816] ksys_mount+0x12d/0x140 [ 26.111429] __x64_sys_mount+0xbe/0x150 [ 26.115394] do_syscall_64+0x1b9/0x820 [ 26.119279] ? syscall_slow_exit_work+0x500/0x500 [ 26.124125] ? syscall_return_slowpath+0x5e0/0x5e0 [ 26.129057] ? syscall_return_slowpath+0x31d/0x5e0 [ 26.133975] ? prepare_exit_to_usermode+0x291/0x3b0 [ 26.138986] ? perf_trace_sys_enter+0xb10/0xb10 [ 26.143663] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.148499] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.153669] RIP: 0033:0x440179 [ 26.156841] 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 [ 26.176111] RSP: 002b:00007ffd0dfcf378 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 26.183815] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440179 [ 26.191072] RDX: 0000000020000080 RSI: 0000000020000000 RDI: 0000000000000000 [ 26.198420] RBP: 0030656c69662f2e R08: 0000000020000340 R09: 00000000004002c8 [ 26.205682] R10: 0000000000000000 R11: 0000000000000206 R12: 64663d736e617274 [ 26.212963] R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000 [ 26.220222] [ 26.221844] Allocated by task 4461: [ 26.225461] save_stack+0x43/0xd0 [ 26.228900] kasan_kmalloc+0xc4/0xe0 [ 26.232596] __kmalloc+0x14e/0x760 [ 26.236123] p9_fcall_alloc+0x1e/0x90 [ 26.239902] p9_client_prepare_req.part.9+0x754/0xcd0 [ 26.245086] p9_client_rpc+0x1bd/0x1400 [ 26.249062] p9_client_create+0xd09/0x16c9 [ 26.253295] v9fs_session_init+0x21a/0x1a80 [ 26.257599] v9fs_mount+0x7c/0x900 [ 26.261146] legacy_get_tree+0x118/0x440 [ 26.265196] vfs_get_tree+0x1cb/0x5c0 [ 26.268985] do_mount+0x6c1/0x1fb0 [ 26.272511] ksys_mount+0x12d/0x140 [ 26.276116] __x64_sys_mount+0xbe/0x150 [ 26.280080] do_syscall_64+0x1b9/0x820 [ 26.283965] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.289144] [ 26.290765] Freed by task 0: [ 26.293756] (stack is not available) [ 26.297443] [ 26.299052] The buggy address belongs to the object at ffff8801d3d78600 [ 26.299052] which belongs to the cache kmalloc-16384 of size 16384 [ 26.312043] The buggy address is located 45 bytes inside of [ 26.312043] 16384-byte region [ffff8801d3d78600, ffff8801d3d7c600) [ 26.323983] The buggy address belongs to the page: [ 26.328908] page:ffffea00074f5e00 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 26.338872] flags: 0x2fffc0000008100(slab|head) [ 26.343538] raw: 02fffc0000008100 ffffea0007382408 ffff8801da801c48 ffff8801da802200 [ 26.351412] raw: 0000000000000000 ffff8801d3d78600 0000000100000001 0000000000000000 [ 26.359279] page dumped because: kasan: bad access detected [ 26.364978] [ 26.366582] Memory state around the buggy address: [ 26.371492] ffff8801d3d7a500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.378839] ffff8801d3d7a580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 26.386187] >ffff8801d3d7a600: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 26.393522] ^ [ 26.397909] ffff8801d3d7a680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.405261] ffff8801d3d7a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 26.412606] ================================================================== [ 26.420083] Kernel panic - not syncing: panic_on_warn set ... [ 26.420083] [ 26.427446] CPU: 1 PID: 4461 Comm: syz-executor073 Tainted: G B 4.18.0-rc3-next-20180706+ #1 [ 26.437314] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.446659] Call Trace: [ 26.449237] dump_stack+0x1c9/0x2b4 [ 26.452844] ? dump_stack_print_info.cold.2+0x52/0x52 [ 26.458041] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.462794] panic+0x238/0x4e7 [ 26.465966] ? add_taint.cold.5+0x16/0x16 [ 26.470123] ? do_raw_spin_unlock+0xa7/0x2f0 [ 26.474512] ? pdu_read+0x90/0xd0 [ 26.477947] kasan_end_report+0x47/0x4f [ 26.481901] kasan_report.cold.7+0x76/0x30d [ 26.486205] check_memory_region+0x13e/0x1b0 [ 26.490605] memcpy+0x23/0x50 [ 26.493693] pdu_read+0x90/0xd0 [ 26.496957] p9pdu_readf+0x579/0x2170 [ 26.500738] ? p9pdu_writef+0xe0/0xe0 [ 26.504522] ? ksys_dup3+0x690/0x690 [ 26.508217] ? check_same_owner+0x340/0x340 [ 26.512520] ? p9_fd_poll+0x2b0/0x2b0 [ 26.516304] ? kasan_kmalloc+0xc4/0xe0 [ 26.520176] ? kasan_unpoison_shadow+0x35/0x50 [ 26.524753] ? p9_fd_show_options+0x1c0/0x1c0 [ 26.529228] ? __raw_spin_lock_init+0x2d/0x100 [ 26.533790] p9_client_create+0xde0/0x16c9 [ 26.538012] ? p9_client_read+0xc60/0xc60 [ 26.542148] ? kasan_check_read+0x11/0x20 [ 26.546289] ? lock_acquire+0x1e4/0x540 [ 26.550245] ? fs_reclaim_acquire+0x20/0x20 [ 26.554548] ? lock_release+0xa30/0xa30 [ 26.558503] ? __lockdep_init_map+0x105/0x590 [ 26.562983] ? kasan_check_write+0x14/0x20 [ 26.567208] ? __init_rwsem+0x1cc/0x2a0 [ 26.571167] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 26.576165] ? __kmalloc_track_caller+0x311/0x760 [ 26.581075] ? save_stack+0xa9/0xd0 [ 26.584695] ? save_stack+0x43/0xd0 [ 26.588312] ? kasan_kmalloc+0xc4/0xe0 [ 26.592191] ? kmem_cache_alloc_trace+0x152/0x780 [ 26.597024] ? memcpy+0x45/0x50 [ 26.600291] v9fs_session_init+0x21a/0x1a80 [ 26.604596] ? rcu_note_context_switch+0x730/0x730 [ 26.609504] ? do_mount+0x69e/0x1fb0 [ 26.613202] ? lock_acquire+0x1e4/0x540 [ 26.617168] ? v9fs_show_options+0x7e0/0x7e0 [ 26.621558] ? lock_release+0xa30/0xa30 [ 26.625515] ? check_same_owner+0x340/0x340 [ 26.629830] ? lock_downgrade+0x8f0/0x8f0 [ 26.633963] ? kasan_unpoison_shadow+0x35/0x50 [ 26.638524] ? kasan_kmalloc+0xc4/0xe0 [ 26.642404] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.647239] ? kasan_unpoison_shadow+0x35/0x50 [ 26.651813] ? kasan_kmalloc+0xc4/0xe0 [ 26.655682] v9fs_mount+0x7c/0x900 [ 26.659215] ? v9fs_drop_inode+0x150/0x150 [ 26.663429] legacy_get_tree+0x118/0x440 [ 26.667472] vfs_get_tree+0x1cb/0x5c0 [ 26.671259] do_mount+0x6c1/0x1fb0 [ 26.674778] ? check_same_owner+0x340/0x340 [ 26.679079] ? lock_release+0xa30/0xa30 [ 26.683041] ? copy_mount_string+0x40/0x40 [ 26.687270] ? kasan_kmalloc+0xc4/0xe0 [ 26.691141] ? kmem_cache_alloc_trace+0x318/0x780 [ 26.695976] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 26.701494] ? _copy_from_user+0xdf/0x150 [ 26.705623] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 26.711139] ? copy_mount_options+0x285/0x380 [ 26.715623] ksys_mount+0x12d/0x140 [ 26.719233] __x64_sys_mount+0xbe/0x150 [ 26.723191] do_syscall_64+0x1b9/0x820 [ 26.727057] ? syscall_slow_exit_work+0x500/0x500 [ 26.731878] ? syscall_return_slowpath+0x5e0/0x5e0 [ 26.736806] ? syscall_return_slowpath+0x31d/0x5e0 [ 26.741722] ? prepare_exit_to_usermode+0x291/0x3b0 [ 26.746722] ? perf_trace_sys_enter+0xb10/0xb10 [ 26.751372] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.756199] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 26.761388] RIP: 0033:0x440179 [ 26.764556] 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 [ 26.783696] RSP: 002b:00007ffd0dfcf378 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 26.791398] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000440179 [ 26.798648] RDX: 0000000020000080 RSI: 0000000020000000 RDI: 0000000000000000 [ 26.805895] RBP: 0030656c69662f2e R08: 0000000020000340 R09: 00000000004002c8 [ 26.813144] R10: 0000000000000000 R11: 0000000000000206 R12: 64663d736e617274 [ 26.820392] R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000 [ 26.828285] Dumping ftrace buffer: [ 26.831804] (ftrace buffer empty) [ 26.835492] Kernel Offset: disabled [ 26.839102] Rebooting in 86400 seconds..