[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 16.227327] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.530230] random: sshd: uninitialized urandom read (32 bytes read) [ 20.880301] random: sshd: uninitialized urandom read (32 bytes read) [ 21.601792] random: sshd: uninitialized urandom read (32 bytes read) [ 21.738893] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.200' (ECDSA) to the list of known hosts. [ 27.252948] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program [ 27.338883] ================================================================== [ 27.346307] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 27.352441] Read of size 32860 at addr ffff8801c991852d by task syz-executor422/4461 [ 27.360296] [ 27.362012] CPU: 1 PID: 4461 Comm: syz-executor422 Not tainted 4.18.0-rc3-next-20180709+ #2 [ 27.370480] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.379825] Call Trace: [ 27.382410] dump_stack+0x1c9/0x2b4 [ 27.386018] ? dump_stack_print_info.cold.2+0x52/0x52 [ 27.391366] ? printk+0xa7/0xcf [ 27.394623] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 27.399375] ? pdu_read+0x90/0xd0 [ 27.402832] print_address_description+0x6c/0x20b [ 27.407652] ? pdu_read+0x90/0xd0 [ 27.411172] kasan_report.cold.7+0x242/0x30d [ 27.415560] check_memory_region+0x13e/0x1b0 [ 27.419962] memcpy+0x23/0x50 [ 27.423049] pdu_read+0x90/0xd0 [ 27.426309] p9pdu_readf+0x579/0x2170 [ 27.430092] ? p9pdu_writef+0xe0/0xe0 [ 27.433879] ? ksys_dup3+0x690/0x690 [ 27.437577] ? check_same_owner+0x340/0x340 [ 27.441879] ? p9_fd_poll+0x2b0/0x2b0 [ 27.445664] ? kasan_kmalloc+0xc4/0xe0 [ 27.449535] ? kasan_unpoison_shadow+0x35/0x50 [ 27.454099] ? p9_fd_show_options+0x1c0/0x1c0 [ 27.458583] ? __raw_spin_lock_init+0x2d/0x100 [ 27.463157] p9_client_create+0xde0/0x16c9 [ 27.467386] ? p9_client_read+0xc60/0xc60 [ 27.471516] ? kasan_check_read+0x11/0x20 [ 27.475647] ? lock_acquire+0x1e4/0x540 [ 27.479605] ? fs_reclaim_acquire+0x20/0x20 [ 27.483911] ? lock_release+0xa30/0xa30 [ 27.487866] ? __lockdep_init_map+0x105/0x590 [ 27.492356] ? kasan_check_write+0x14/0x20 [ 27.496569] ? __init_rwsem+0x1cc/0x2a0 [ 27.500535] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 27.505562] ? __kmalloc_track_caller+0x311/0x760 [ 27.510401] ? save_stack+0xa9/0xd0 [ 27.514015] ? save_stack+0x43/0xd0 [ 27.517634] ? kasan_kmalloc+0xc4/0xe0 [ 27.521501] ? kmem_cache_alloc_trace+0x152/0x780 [ 27.526322] ? memcpy+0x45/0x50 [ 27.529587] v9fs_session_init+0x21a/0x1a80 [ 27.533893] ? rcu_note_context_switch+0x730/0x730 [ 27.538815] ? do_mount+0x69e/0x1fb0 [ 27.542524] ? lock_acquire+0x1e4/0x540 [ 27.546492] ? v9fs_show_options+0x7e0/0x7e0 [ 27.550881] ? lock_release+0xa30/0xa30 [ 27.554836] ? check_same_owner+0x340/0x340 [ 27.559138] ? kasan_unpoison_shadow+0x35/0x50 [ 27.563712] ? kasan_kmalloc+0xc4/0xe0 [ 27.568199] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.573039] ? kasan_unpoison_shadow+0x35/0x50 [ 27.577602] ? kasan_kmalloc+0xc4/0xe0 [ 27.581471] v9fs_mount+0x7c/0x900 [ 27.585091] ? v9fs_drop_inode+0x150/0x150 [ 27.589326] legacy_get_tree+0x118/0x440 [ 27.593382] vfs_get_tree+0x1cb/0x5c0 [ 27.597189] do_mount+0x6c1/0x1fb0 [ 27.600712] ? check_same_owner+0x340/0x340 [ 27.605018] ? lock_release+0xa30/0xa30 [ 27.608973] ? copy_mount_string+0x40/0x40 [ 27.613209] ? kasan_kmalloc+0xc4/0xe0 [ 27.617076] ? kmem_cache_alloc_trace+0x318/0x780 [ 27.621914] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 27.627440] ? _copy_from_user+0xdf/0x150 [ 27.631582] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.637111] ? copy_mount_options+0x285/0x380 [ 27.641598] ksys_mount+0x12d/0x140 [ 27.645222] __x64_sys_mount+0xbe/0x150 [ 27.649217] do_syscall_64+0x1b9/0x820 [ 27.653084] ? syscall_return_slowpath+0x5e0/0x5e0 [ 27.658110] ? syscall_return_slowpath+0x31d/0x5e0 [ 27.663025] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 27.668043] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 27.673562] ? prepare_exit_to_usermode+0x291/0x3b0 [ 27.678570] ? perf_trace_sys_enter+0xb10/0xb10 [ 27.683228] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.688055] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.693223] RIP: 0033:0x4408d9 [ 27.696402] Code: e8 8c b3 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 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 27.715522] RSP: 002b:00007ffe88ea6ab8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 27.723222] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004408d9 [ 27.730485] RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000000000000 [ 27.737735] RBP: 0000000000000000 R08: 0000000020000380 R09: 00000000004002c8 [ 27.744987] R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000006ac7 [ 27.752247] R13: 0000000000401e30 R14: 0000000000000000 R15: 0000000000000000 [ 27.759513] [ 27.761131] Allocated by task 4461: [ 27.764757] save_stack+0x43/0xd0 [ 27.768209] kasan_kmalloc+0xc4/0xe0 [ 27.771920] __kmalloc+0x14e/0x760 [ 27.775445] p9_fcall_alloc+0x1e/0x90 [ 27.779261] p9_client_prepare_req.part.9+0x754/0xcd0 [ 27.784529] p9_client_rpc+0x1bd/0x1400 [ 27.788482] p9_client_create+0xd09/0x16c9 [ 27.792698] v9fs_session_init+0x21a/0x1a80 [ 27.797008] v9fs_mount+0x7c/0x900 [ 27.800537] legacy_get_tree+0x118/0x440 [ 27.804578] vfs_get_tree+0x1cb/0x5c0 [ 27.808360] do_mount+0x6c1/0x1fb0 [ 27.811880] ksys_mount+0x12d/0x140 [ 27.815484] __x64_sys_mount+0xbe/0x150 [ 27.819439] do_syscall_64+0x1b9/0x820 [ 27.823317] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 27.828480] [ 27.830086] Freed by task 0: [ 27.833078] (stack is not available) [ 27.836777] [ 27.838399] The buggy address belongs to the object at ffff8801c9918500 [ 27.838399] which belongs to the cache kmalloc-16384 of size 16384 [ 27.851406] The buggy address is located 45 bytes inside of [ 27.851406] 16384-byte region [ffff8801c9918500, ffff8801c991c500) [ 27.863359] The buggy address belongs to the page: [ 27.868273] page:ffffea0007264600 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 27.878222] flags: 0x2fffc0000008100(slab|head) [ 27.882872] raw: 02fffc0000008100 ffffea0006b51608 ffff8801da801c48 ffff8801da802200 [ 27.890738] raw: 0000000000000000 ffff8801c9918500 0000000100000001 0000000000000000 [ 27.898606] page dumped because: kasan: bad access detected [ 27.904378] [ 27.905997] Memory state around the buggy address: [ 27.910908] ffff8801c991a400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.918259] ffff8801c991a480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 27.925606] >ffff8801c991a500: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 27.933573] ^ [ 27.937959] ffff8801c991a580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.945295] ffff8801c991a600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 27.952641] ================================================================== [ 27.960110] Kernel panic - not syncing: panic_on_warn set ... [ 27.960110] [ 27.967469] CPU: 1 PID: 4461 Comm: syz-executor422 Tainted: G B 4.18.0-rc3-next-20180709+ #2 [ 27.977328] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.986661] Call Trace: [ 27.989249] dump_stack+0x1c9/0x2b4 [ 27.992875] ? dump_stack_print_info.cold.2+0x52/0x52 [ 27.998137] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 28.002886] panic+0x238/0x4e7 [ 28.006061] ? add_taint.cold.5+0x16/0x16 [ 28.010199] ? do_raw_spin_unlock+0xa7/0x2f0 [ 28.014593] ? pdu_read+0x90/0xd0 [ 28.018040] kasan_end_report+0x47/0x4f [ 28.021998] kasan_report.cold.7+0x76/0x30d [ 28.026310] check_memory_region+0x13e/0x1b0 [ 28.030698] memcpy+0x23/0x50 [ 28.033785] pdu_read+0x90/0xd0 [ 28.037044] p9pdu_readf+0x579/0x2170 [ 28.041010] ? p9pdu_writef+0xe0/0xe0 [ 28.044795] ? ksys_dup3+0x690/0x690 [ 28.048489] ? check_same_owner+0x340/0x340 [ 28.052788] ? p9_fd_poll+0x2b0/0x2b0 [ 28.056748] ? kasan_kmalloc+0xc4/0xe0 [ 28.060616] ? kasan_unpoison_shadow+0x35/0x50 [ 28.065194] ? p9_fd_show_options+0x1c0/0x1c0 [ 28.069670] ? __raw_spin_lock_init+0x2d/0x100 [ 28.074252] p9_client_create+0xde0/0x16c9 [ 28.078480] ? p9_client_read+0xc60/0xc60 [ 28.082608] ? kasan_check_read+0x11/0x20 [ 28.086750] ? lock_acquire+0x1e4/0x540 [ 28.090705] ? fs_reclaim_acquire+0x20/0x20 [ 28.095023] ? lock_release+0xa30/0xa30 [ 28.098978] ? __lockdep_init_map+0x105/0x590 [ 28.103458] ? kasan_check_write+0x14/0x20 [ 28.107673] ? __init_rwsem+0x1cc/0x2a0 [ 28.111628] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 28.116624] ? __kmalloc_track_caller+0x311/0x760 [ 28.121445] ? save_stack+0xa9/0xd0 [ 28.125063] ? save_stack+0x43/0xd0 [ 28.128682] ? kasan_kmalloc+0xc4/0xe0 [ 28.132553] ? kmem_cache_alloc_trace+0x152/0x780 [ 28.137477] ? memcpy+0x45/0x50 [ 28.140749] v9fs_session_init+0x21a/0x1a80 [ 28.145052] ? rcu_note_context_switch+0x730/0x730 [ 28.149962] ? do_mount+0x69e/0x1fb0 [ 28.153672] ? lock_acquire+0x1e4/0x540 [ 28.157629] ? v9fs_show_options+0x7e0/0x7e0 [ 28.162024] ? lock_release+0xa30/0xa30 [ 28.165980] ? check_same_owner+0x340/0x340 [ 28.170284] ? kasan_unpoison_shadow+0x35/0x50 [ 28.174865] ? kasan_kmalloc+0xc4/0xe0 [ 28.178750] ? kmem_cache_alloc_trace+0x318/0x780 [ 28.183587] ? kasan_unpoison_shadow+0x35/0x50 [ 28.188157] ? kasan_kmalloc+0xc4/0xe0 [ 28.192038] v9fs_mount+0x7c/0x900 [ 28.195576] ? v9fs_drop_inode+0x150/0x150 [ 28.199814] legacy_get_tree+0x118/0x440 [ 28.203871] vfs_get_tree+0x1cb/0x5c0 [ 28.207657] do_mount+0x6c1/0x1fb0 [ 28.211179] ? check_same_owner+0x340/0x340 [ 28.215493] ? lock_release+0xa30/0xa30 [ 28.219449] ? copy_mount_string+0x40/0x40 [ 28.223664] ? kasan_kmalloc+0xc4/0xe0 [ 28.227534] ? kmem_cache_alloc_trace+0x318/0x780 [ 28.232370] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 28.237890] ? _copy_from_user+0xdf/0x150 [ 28.242370] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 28.247889] ? copy_mount_options+0x285/0x380 [ 28.252385] ksys_mount+0x12d/0x140 [ 28.256019] __x64_sys_mount+0xbe/0x150 [ 28.259990] do_syscall_64+0x1b9/0x820 [ 28.263856] ? syscall_return_slowpath+0x5e0/0x5e0 [ 28.268777] ? syscall_return_slowpath+0x31d/0x5e0 [ 28.273686] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 28.278684] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 28.284203] ? prepare_exit_to_usermode+0x291/0x3b0 [ 28.289214] ? perf_trace_sys_enter+0xb10/0xb10 [ 28.293866] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 28.298696] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 28.303867] RIP: 0033:0x4408d9 [ 28.307051] Code: e8 8c b3 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 3b 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 28.326185] RSP: 002b:00007ffe88ea6ab8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5 [ 28.333884] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004408d9 [ 28.341150] RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000000000000 [ 28.348404] RBP: 0000000000000000 R08: 0000000020000380 R09: 00000000004002c8 [ 28.355652] R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000006ac7 [ 28.362901] R13: 0000000000401e30 R14: 0000000000000000 R15: 0000000000000000 [ 28.370637] Dumping ftrace buffer: [ 28.374158] (ftrace buffer empty) [ 28.377849] Kernel Offset: disabled [ 28.381467] Rebooting in 86400 seconds..