[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 14.776276] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.511131] random: sshd: uninitialized urandom read (32 bytes read) [ 18.802519] random: sshd: uninitialized urandom read (32 bytes read) [ 19.525661] random: sshd: uninitialized urandom read (32 bytes read) [ 30.940154] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.15.205' (ECDSA) to the list of known hosts. [ 36.313628] 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 executing program executing program executing program [ 36.930950] ================================================================== [ 36.938349] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 36.944471] Read of size 36766 at addr ffff8801c7f6902d by task syz-executor205/4425 [ 36.952362] [ 36.953972] CPU: 1 PID: 4425 Comm: syz-executor205 Not tainted 4.18.0-rc5-next-20180720+ #12 [ 36.962518] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 36.971857] Call Trace: [ 36.974423] dump_stack+0x1c9/0x2b4 [ 36.978028] ? dump_stack_print_info.cold.2+0x52/0x52 [ 36.983198] ? printk+0xa7/0xcf [ 36.986453] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 36.991185] ? pdu_read+0x90/0xd0 [ 36.994629] print_address_description+0x6c/0x20b [ 36.999447] ? pdu_read+0x90/0xd0 [ 37.002877] kasan_report.cold.7+0x242/0x30d [ 37.007277] check_memory_region+0x13e/0x1b0 [ 37.011666] memcpy+0x23/0x50 [ 37.014750] pdu_read+0x90/0xd0 [ 37.018014] p9pdu_readf+0x579/0x2170 [ 37.021796] ? p9pdu_writef+0xe0/0xe0 [ 37.025579] ? ksys_dup3+0x690/0x690 [ 37.029285] ? check_same_owner+0x340/0x340 [ 37.033590] ? p9_fd_poll+0x2b0/0x2b0 [ 37.037379] ? finish_wait+0x430/0x430 [ 37.041249] ? p9_fd_show_options+0x1c0/0x1c0 [ 37.045725] p9_client_create+0x6d0/0x1537 [ 37.049939] ? p9_client_read+0xbb0/0xbb0 [ 37.054066] ? lock_acquire+0x1e4/0x540 [ 37.058016] ? fs_reclaim_acquire+0x20/0x20 [ 37.062326] ? lock_release+0xa30/0xa30 [ 37.066278] ? __lockdep_init_map+0x105/0x590 [ 37.070753] ? kasan_check_write+0x14/0x20 [ 37.074963] ? __init_rwsem+0x1cc/0x2a0 [ 37.078916] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 37.083908] ? __kmalloc_track_caller+0x311/0x760 [ 37.088727] ? save_stack+0xa9/0xd0 [ 37.092339] ? save_stack+0x43/0xd0 [ 37.095942] ? kasan_kmalloc+0xc4/0xe0 [ 37.099804] ? memcpy+0x45/0x50 [ 37.103062] v9fs_session_init+0x21a/0x1a80 [ 37.107361] ? rcu_note_context_switch+0x730/0x730 [ 37.112282] ? legacy_parse_monolithic+0xde/0x1e0 [ 37.117105] ? v9fs_show_options+0x7e0/0x7e0 [ 37.121502] ? lock_release+0xa30/0xa30 [ 37.125458] ? check_same_owner+0x340/0x340 [ 37.129758] ? lock_downgrade+0x8f0/0x8f0 [ 37.133886] ? kasan_unpoison_shadow+0x35/0x50 [ 37.138442] ? kasan_kmalloc+0xc4/0xe0 [ 37.142318] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.147148] ? kasan_unpoison_shadow+0x35/0x50 [ 37.151705] ? kasan_kmalloc+0xc4/0xe0 [ 37.155572] v9fs_mount+0x7c/0x900 [ 37.159107] ? v9fs_drop_inode+0x150/0x150 [ 37.163319] legacy_get_tree+0x131/0x460 [ 37.167368] vfs_get_tree+0x1cb/0x5c0 [ 37.171146] do_mount+0x6f2/0x1e20 [ 37.174663] ? check_same_owner+0x340/0x340 [ 37.178975] ? lock_release+0xa30/0xa30 [ 37.182938] ? copy_mount_string+0x40/0x40 [ 37.187149] ? kasan_kmalloc+0xc4/0xe0 [ 37.191026] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.195849] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 37.201362] ? _copy_from_user+0xdf/0x150 [ 37.205490] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.211002] ? copy_mount_options+0x285/0x380 [ 37.215473] ksys_mount+0x12d/0x140 [ 37.219078] __x64_sys_mount+0xbe/0x150 [ 37.223033] do_syscall_64+0x1b9/0x820 [ 37.226900] ? syscall_return_slowpath+0x5e0/0x5e0 [ 37.231817] ? syscall_return_slowpath+0x31d/0x5e0 [ 37.236724] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 37.241717] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.247230] ? prepare_exit_to_usermode+0x291/0x3b0 [ 37.252221] ? perf_trace_sys_enter+0xb10/0xb10 [ 37.256876] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.261699] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.266864] RIP: 0033:0x445e29 [ 37.270028] Code: e8 ec ba 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 [ 37.289153] RSP: 002b:00007fd5cc3e5da8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 37.296846] RAX: ffffffffffffffda RBX: 00000000006dbc44 RCX: 0000000000445e29 [ 37.304095] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 37.311354] RBP: 00000000006dbc40 R08: 00000000200001c0 R09: 0000000000000000 [ 37.318598] R10: 0000000000000000 R11: 0000000000000202 R12: 0030656c69662f2e [ 37.325845] R13: 6d64692e73666963 R14: 64663d736e617274 R15: 0000000000000001 [ 37.333092] [ 37.334696] Allocated by task 4425: [ 37.338299] save_stack+0x43/0xd0 [ 37.341727] kasan_kmalloc+0xc4/0xe0 [ 37.345416] __kmalloc+0x14e/0x760 [ 37.348931] p9_fcall_alloc+0x1e/0x90 [ 37.352709] p9_client_prepare_req.part.8+0x132/0xa00 [ 37.357875] p9_client_rpc+0x242/0x1330 [ 37.361827] p9_client_create+0xca4/0x1537 [ 37.366048] v9fs_session_init+0x21a/0x1a80 [ 37.370344] v9fs_mount+0x7c/0x900 [ 37.373860] legacy_get_tree+0x131/0x460 [ 37.377910] vfs_get_tree+0x1cb/0x5c0 [ 37.381688] do_mount+0x6f2/0x1e20 [ 37.385214] ksys_mount+0x12d/0x140 [ 37.388818] __x64_sys_mount+0xbe/0x150 [ 37.392766] do_syscall_64+0x1b9/0x820 [ 37.396633] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.401795] [ 37.403398] Freed by task 0: [ 37.406386] (stack is not available) [ 37.410069] [ 37.411684] The buggy address belongs to the object at ffff8801c7f69000 [ 37.411684] which belongs to the cache kmalloc-16384 of size 16384 [ 37.424677] The buggy address is located 45 bytes inside of [ 37.424677] 16384-byte region [ffff8801c7f69000, ffff8801c7f6d000) [ 37.436631] The buggy address belongs to the page: [ 37.441559] page:ffffea00071fda00 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 37.451505] flags: 0x2fffc0000010200(slab|head) [ 37.456155] raw: 02fffc0000010200 ffffea0007150808 ffff8801da801c48 ffff8801da802200 [ 37.464016] raw: 0000000000000000 ffff8801c7f69000 0000000100000001 0000000000000000 [ 37.471870] page dumped because: kasan: bad access detected [ 37.477563] [ 37.479173] Memory state around the buggy address: [ 37.484076] ffff8801c7f6af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.491411] ffff8801c7f6af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 37.498757] >ffff8801c7f6b000: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 37.506091] ^ [ 37.510472] ffff8801c7f6b080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 37.517808] ffff8801c7f6b100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 37.525140] ================================================================== [ 37.532563] Kernel panic - not syncing: panic_on_warn set ... [ 37.532563] [ 37.539914] CPU: 1 PID: 4425 Comm: syz-executor205 Tainted: G B 4.18.0-rc5-next-20180720+ #12 [ 37.549854] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 37.559183] Call Trace: [ 37.561752] dump_stack+0x1c9/0x2b4 [ 37.565356] ? dump_stack_print_info.cold.2+0x52/0x52 [ 37.570526] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 37.575263] panic+0x238/0x4e7 [ 37.578435] ? add_taint.cold.5+0x16/0x16 [ 37.582562] ? do_raw_spin_unlock+0xa7/0x2f0 [ 37.586950] ? pdu_read+0x90/0xd0 [ 37.590378] kasan_end_report+0x47/0x4f [ 37.594328] kasan_report.cold.7+0x76/0x30d [ 37.598633] check_memory_region+0x13e/0x1b0 [ 37.603016] memcpy+0x23/0x50 [ 37.606100] pdu_read+0x90/0xd0 [ 37.609356] p9pdu_readf+0x579/0x2170 [ 37.613133] ? p9pdu_writef+0xe0/0xe0 [ 37.616911] ? ksys_dup3+0x690/0x690 [ 37.620603] ? check_same_owner+0x340/0x340 [ 37.624903] ? p9_fd_poll+0x2b0/0x2b0 [ 37.628680] ? finish_wait+0x430/0x430 [ 37.632562] ? p9_fd_show_options+0x1c0/0x1c0 [ 37.637038] p9_client_create+0x6d0/0x1537 [ 37.641250] ? p9_client_read+0xbb0/0xbb0 [ 37.645375] ? lock_acquire+0x1e4/0x540 [ 37.649329] ? fs_reclaim_acquire+0x20/0x20 [ 37.653630] ? lock_release+0xa30/0xa30 [ 37.657581] ? __lockdep_init_map+0x105/0x590 [ 37.662056] ? kasan_check_write+0x14/0x20 [ 37.666268] ? __init_rwsem+0x1cc/0x2a0 [ 37.670217] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 37.675210] ? __kmalloc_track_caller+0x311/0x760 [ 37.680026] ? save_stack+0xa9/0xd0 [ 37.683629] ? save_stack+0x43/0xd0 [ 37.687230] ? kasan_kmalloc+0xc4/0xe0 [ 37.691091] ? memcpy+0x45/0x50 [ 37.694363] v9fs_session_init+0x21a/0x1a80 [ 37.698661] ? rcu_note_context_switch+0x730/0x730 [ 37.703568] ? legacy_parse_monolithic+0xde/0x1e0 [ 37.708389] ? v9fs_show_options+0x7e0/0x7e0 [ 37.712776] ? lock_release+0xa30/0xa30 [ 37.716728] ? check_same_owner+0x340/0x340 [ 37.721028] ? lock_downgrade+0x8f0/0x8f0 [ 37.725155] ? kasan_unpoison_shadow+0x35/0x50 [ 37.729726] ? kasan_kmalloc+0xc4/0xe0 [ 37.733603] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.738433] ? kasan_unpoison_shadow+0x35/0x50 [ 37.743009] ? kasan_kmalloc+0xc4/0xe0 [ 37.746893] v9fs_mount+0x7c/0x900 [ 37.750415] ? v9fs_drop_inode+0x150/0x150 [ 37.754629] legacy_get_tree+0x131/0x460 [ 37.758668] vfs_get_tree+0x1cb/0x5c0 [ 37.762458] do_mount+0x6f2/0x1e20 [ 37.765979] ? check_same_owner+0x340/0x340 [ 37.770279] ? lock_release+0xa30/0xa30 [ 37.774241] ? copy_mount_string+0x40/0x40 [ 37.778462] ? kasan_kmalloc+0xc4/0xe0 [ 37.782330] ? kmem_cache_alloc_trace+0x318/0x780 [ 37.787161] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 37.792685] ? _copy_from_user+0xdf/0x150 [ 37.796809] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.802324] ? copy_mount_options+0x285/0x380 [ 37.806795] ksys_mount+0x12d/0x140 [ 37.810411] __x64_sys_mount+0xbe/0x150 [ 37.814361] do_syscall_64+0x1b9/0x820 [ 37.818225] ? syscall_return_slowpath+0x5e0/0x5e0 [ 37.823142] ? syscall_return_slowpath+0x31d/0x5e0 [ 37.828059] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 37.833053] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 37.838573] ? prepare_exit_to_usermode+0x291/0x3b0 [ 37.843568] ? perf_trace_sys_enter+0xb10/0xb10 [ 37.848223] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 37.853049] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 37.858224] RIP: 0033:0x445e29 [ 37.861387] Code: e8 ec ba 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 [ 37.880503] RSP: 002b:00007fd5cc3e5da8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 37.888188] RAX: ffffffffffffffda RBX: 00000000006dbc44 RCX: 0000000000445e29 [ 37.895445] RDX: 0000000020000040 RSI: 0000000020000000 RDI: 0000000000000000 [ 37.902694] RBP: 00000000006dbc40 R08: 00000000200001c0 R09: 0000000000000000 [ 37.909938] R10: 0000000000000000 R11: 0000000000000202 R12: 0030656c69662f2e [ 37.917186] R13: 6d64692e73666963 R14: 64663d736e617274 R15: 0000000000000001 [ 37.924815] Dumping ftrace buffer: [ 37.928328] (ftrace buffer empty) [ 37.932013] Kernel Offset: disabled [ 37.935616] Rebooting in 86400 seconds..