[....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 20.267269] random: sshd: uninitialized urandom read (32 bytes read) [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 23.513099] random: sshd: uninitialized urandom read (32 bytes read) [ 23.872189] random: sshd: uninitialized urandom read (32 bytes read) [ 24.823535] random: sshd: uninitialized urandom read (32 bytes read) [ 24.995232] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.59' (ECDSA) to the list of known hosts. [ 30.498443] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program [ 30.603108] nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based firewall rule not found. Use the iptables CT target to attach helpers instead. [ 30.657343] ================================================================== [ 30.664892] BUG: KASAN: slab-out-of-bounds in pdu_read+0x90/0xd0 [ 30.671076] Read of size 10085 at addr ffff8801c48608ad by task syz-executor300/4548 [ 30.678966] [ 30.680588] CPU: 0 PID: 4548 Comm: syz-executor300 Not tainted 4.18.0-rc4+ #141 [ 30.688125] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 30.697501] Call Trace: [ 30.700099] dump_stack+0x1c9/0x2b4 [ 30.703728] ? dump_stack_print_info.cold.2+0x52/0x52 [ 30.708918] ? printk+0xa7/0xcf [ 30.712203] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 30.716962] ? pdu_read+0x90/0xd0 [ 30.720606] print_address_description+0x6c/0x20b [ 30.725460] ? pdu_read+0x90/0xd0 [ 30.728913] kasan_report.cold.7+0x242/0x2fe [ 30.733379] check_memory_region+0x13e/0x1b0 [ 30.737820] memcpy+0x23/0x50 [ 30.740935] pdu_read+0x90/0xd0 [ 30.744226] p9pdu_readf+0x579/0x2170 [ 30.748054] ? p9pdu_writef+0xe0/0xe0 [ 30.751860] ? __fget+0x414/0x670 [ 30.755339] ? rcu_is_watching+0x61/0x150 [ 30.759501] ? expand_files.part.8+0x9c0/0x9c0 [ 30.764256] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.769301] ? p9_fd_show_options+0x1c0/0x1c0 [ 30.773827] p9_client_create+0xde0/0x16c9 [ 30.778083] ? p9_client_read+0xc60/0xc60 [ 30.782238] ? find_held_lock+0x36/0x1c0 [ 30.786308] ? __lockdep_init_map+0x105/0x590 [ 30.790823] ? kasan_check_write+0x14/0x20 [ 30.795070] ? __init_rwsem+0x1cc/0x2a0 [ 30.799071] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 30.804207] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.809254] ? __kmalloc_track_caller+0x5f5/0x760 [ 30.814105] ? save_stack+0xa9/0xd0 [ 30.817727] ? save_stack+0x43/0xd0 [ 30.821359] ? kasan_kmalloc+0xc4/0xe0 [ 30.825253] ? kmem_cache_alloc_trace+0x152/0x780 [ 30.830113] ? memcpy+0x45/0x50 [ 30.833404] v9fs_session_init+0x21a/0x1a80 [ 30.837727] ? find_held_lock+0x36/0x1c0 [ 30.841793] ? v9fs_show_options+0x7e0/0x7e0 [ 30.846200] ? kasan_check_read+0x11/0x20 [ 30.850446] ? rcu_is_watching+0x8c/0x150 [ 30.854691] ? rcu_pm_notify+0xc0/0xc0 [ 30.858588] ? v9fs_mount+0x61/0x900 [ 30.862313] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.867348] ? kmem_cache_alloc_trace+0x616/0x780 [ 30.872287] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 30.877841] v9fs_mount+0x7c/0x900 [ 30.881398] mount_fs+0xae/0x328 [ 30.884776] vfs_kern_mount.part.34+0xdc/0x4e0 [ 30.889376] ? may_umount+0xb0/0xb0 [ 30.893027] ? _raw_read_unlock+0x22/0x30 [ 30.897197] ? __get_fs_type+0x97/0xc0 [ 30.901120] do_mount+0x581/0x30e0 [ 30.904681] ? copy_mount_string+0x40/0x40 [ 30.908921] ? copy_mount_options+0x5f/0x380 [ 30.913341] ? rcu_read_lock_sched_held+0x108/0x120 [ 30.918454] ? kmem_cache_alloc_trace+0x616/0x780 [ 30.923317] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 30.929407] ? _copy_from_user+0xdf/0x150 [ 30.933584] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.939123] ? copy_mount_options+0x285/0x380 [ 30.943639] ksys_mount+0x12d/0x140 [ 30.947290] __x64_sys_mount+0xbe/0x150 [ 30.951288] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 30.956325] do_syscall_64+0x1b9/0x820 [ 30.960237] ? syscall_return_slowpath+0x5e0/0x5e0 [ 30.965308] ? syscall_return_slowpath+0x31d/0x5e0 [ 30.970261] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 30.975803] ? retint_user+0x18/0x18 [ 30.979524] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.984380] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 30.989674] RIP: 0033:0x440959 [ 30.992862] 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 [ 31.012133] RSP: 002b:00007ffdaba29208 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 31.019934] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440959 [ 31.027352] RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 [ 31.034625] RBP: 0000000000000000 R08: 0000000020000180 R09: 00000000004002c8 [ 31.041895] R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000077b9 [ 31.049158] R13: 0000000000401eb0 R14: 0000000000000000 R15: 0000000000000000 [ 31.056426] [ 31.058051] Allocated by task 4548: [ 31.061678] save_stack+0x43/0xd0 [ 31.065128] kasan_kmalloc+0xc4/0xe0 [ 31.068845] __kmalloc+0x14e/0x760 [ 31.072384] p9_fcall_alloc+0x1e/0x90 [ 31.076186] p9_client_prepare_req.part.8+0x754/0xcd0 [ 31.081397] p9_client_rpc+0x1bd/0x1400 [ 31.085385] p9_client_create+0xd09/0x16c9 [ 31.089621] v9fs_session_init+0x21a/0x1a80 [ 31.094031] v9fs_mount+0x7c/0x900 [ 31.097602] mount_fs+0xae/0x328 [ 31.100966] vfs_kern_mount.part.34+0xdc/0x4e0 [ 31.105568] do_mount+0x581/0x30e0 [ 31.109105] ksys_mount+0x12d/0x140 [ 31.112743] __x64_sys_mount+0xbe/0x150 [ 31.116716] do_syscall_64+0x1b9/0x820 [ 31.120615] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.125791] [ 31.127421] Freed by task 0: [ 31.130437] (stack is not available) [ 31.134140] [ 31.135777] The buggy address belongs to the object at ffff8801c4860880 [ 31.135777] which belongs to the cache kmalloc-16384 of size 16384 [ 31.148793] The buggy address is located 45 bytes inside of [ 31.148793] 16384-byte region [ffff8801c4860880, ffff8801c4864880) [ 31.160752] The buggy address belongs to the page: [ 31.165681] page:ffffea0007121800 count:1 mapcount:0 mapping:ffff8801da802200 index:0x0 compound_mapcount: 0 [ 31.175657] flags: 0x2fffc0000008100(slab|head) [ 31.180335] raw: 02fffc0000008100 ffffea00071a5208 ffffea00070f7408 ffff8801da802200 [ 31.188835] raw: 0000000000000000 ffff8801c4860880 0000000100000001 0000000000000000 [ 31.196711] page dumped because: kasan: bad access detected [ 31.202514] [ 31.204130] Memory state around the buggy address: [ 31.209140] ffff8801c4862780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.216626] ffff8801c4862800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 31.223998] >ffff8801c4862880: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 31.231371] ^ [ 31.235790] ffff8801c4862900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.243145] ffff8801c4862980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 31.250517] ================================================================== [ 31.257881] Disabling lock debugging due to kernel taint [ 31.263434] Kernel panic - not syncing: panic_on_warn set ... [ 31.263434] [ 31.270860] CPU: 0 PID: 4548 Comm: syz-executor300 Tainted: G B 4.18.0-rc4+ #141 [ 31.279718] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.289072] Call Trace: [ 31.291662] dump_stack+0x1c9/0x2b4 [ 31.295283] ? dump_stack_print_info.cold.2+0x52/0x52 [ 31.301528] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 31.306286] panic+0x238/0x4e7 [ 31.309472] ? add_taint.cold.5+0x16/0x16 [ 31.313615] ? do_raw_spin_unlock+0xa7/0x2f0 [ 31.318022] ? pdu_read+0x90/0xd0 [ 31.321475] kasan_end_report+0x47/0x4f [ 31.325439] kasan_report.cold.7+0x76/0x2fe [ 31.329767] check_memory_region+0x13e/0x1b0 [ 31.334197] memcpy+0x23/0x50 [ 31.337308] pdu_read+0x90/0xd0 [ 31.340598] p9pdu_readf+0x579/0x2170 [ 31.344392] ? p9pdu_writef+0xe0/0xe0 [ 31.348194] ? __fget+0x414/0x670 [ 31.351640] ? rcu_is_watching+0x61/0x150 [ 31.355793] ? expand_files.part.8+0x9c0/0x9c0 [ 31.360389] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.365424] ? p9_fd_show_options+0x1c0/0x1c0 [ 31.369921] p9_client_create+0xde0/0x16c9 [ 31.374164] ? p9_client_read+0xc60/0xc60 [ 31.378403] ? find_held_lock+0x36/0x1c0 [ 31.382474] ? __lockdep_init_map+0x105/0x590 [ 31.386983] ? kasan_check_write+0x14/0x20 [ 31.391306] ? __init_rwsem+0x1cc/0x2a0 [ 31.395286] ? do_raw_write_unlock.cold.8+0x49/0x49 [ 31.400300] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.405319] ? __kmalloc_track_caller+0x5f5/0x760 [ 31.410162] ? save_stack+0xa9/0xd0 [ 31.413803] ? save_stack+0x43/0xd0 [ 31.417418] ? kasan_kmalloc+0xc4/0xe0 [ 31.421310] ? kmem_cache_alloc_trace+0x152/0x780 [ 31.426150] ? memcpy+0x45/0x50 [ 31.429452] v9fs_session_init+0x21a/0x1a80 [ 31.433969] ? find_held_lock+0x36/0x1c0 [ 31.438064] ? v9fs_show_options+0x7e0/0x7e0 [ 31.442493] ? kasan_check_read+0x11/0x20 [ 31.446662] ? rcu_is_watching+0x8c/0x150 [ 31.450828] ? rcu_pm_notify+0xc0/0xc0 [ 31.454870] ? v9fs_mount+0x61/0x900 [ 31.458615] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.463840] ? kmem_cache_alloc_trace+0x616/0x780 [ 31.468750] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 31.474310] v9fs_mount+0x7c/0x900 [ 31.477895] mount_fs+0xae/0x328 [ 31.481299] vfs_kern_mount.part.34+0xdc/0x4e0 [ 31.485898] ? may_umount+0xb0/0xb0 [ 31.489541] ? _raw_read_unlock+0x22/0x30 [ 31.493706] ? __get_fs_type+0x97/0xc0 [ 31.497592] do_mount+0x581/0x30e0 [ 31.501134] ? copy_mount_string+0x40/0x40 [ 31.505373] ? copy_mount_options+0x5f/0x380 [ 31.509779] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.514831] ? kmem_cache_alloc_trace+0x616/0x780 [ 31.519702] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 31.525254] ? _copy_from_user+0xdf/0x150 [ 31.529417] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.534966] ? copy_mount_options+0x285/0x380 [ 31.539475] ksys_mount+0x12d/0x140 [ 31.543135] __x64_sys_mount+0xbe/0x150 [ 31.547294] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.552337] do_syscall_64+0x1b9/0x820 [ 31.556250] ? syscall_return_slowpath+0x5e0/0x5e0 [ 31.561202] ? syscall_return_slowpath+0x31d/0x5e0 [ 31.566158] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 31.571713] ? retint_user+0x18/0x18 [ 31.575441] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 31.580295] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 31.585485] RIP: 0033:0x440959 [ 31.588672] 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 [ 31.608196] RSP: 002b:00007ffdaba29208 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5 [ 31.615924] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440959 [ 31.623205] RDX: 0000000020000100 RSI: 00000000200000c0 RDI: 0000000000000000 [ 31.630503] RBP: 0000000000000000 R08: 0000000020000180 R09: 00000000004002c8 [ 31.637771] R10: 0000000000000000 R11: 0000000000000202 R12: 00000000000077b9 [ 31.645124] R13: 0000000000401eb0 R14: 0000000000000000 R15: 0000000000000000 [ 31.653148] Dumping ftrace buffer: [ 31.656700] (ftrace buffer empty) [ 31.660393] Kernel Offset: disabled [ 31.664162] Rebooting in 86400 seconds..