[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 28.493237] kauditd_printk_skb: 7 callbacks suppressed [ 28.493250] audit: type=1800 audit(1543148571.843:29): pid=5878 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 28.526131] audit: type=1800 audit(1543148571.843:30): pid=5878 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.15.195' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 44.728136] ================================================================== [ 44.735584] BUG: KASAN: slab-out-of-bounds in queue_stack_map_push_elem+0x185/0x290 [ 44.743370] Write of size 262146 at addr ffff8801c4946708 by task syz-executor949/6034 [ 44.751401] [ 44.753033] CPU: 1 PID: 6034 Comm: syz-executor949 Not tainted 4.20.0-rc1-next-20181109+ #110 [ 44.761675] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.771007] Call Trace: [ 44.773579] dump_stack+0x244/0x39d [ 44.777207] ? dump_stack_print_info.cold.1+0x20/0x20 [ 44.782411] ? printk+0xa7/0xcf [ 44.785692] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 44.790450] print_address_description.cold.7+0x9/0x1ff [ 44.795799] kasan_report.cold.8+0x242/0x309 [ 44.800187] ? queue_stack_map_push_elem+0x185/0x290 [ 44.805278] check_memory_region+0x13e/0x1b0 [ 44.809671] memcpy+0x37/0x50 [ 44.812766] queue_stack_map_push_elem+0x185/0x290 [ 44.817695] ? queue_map_pop_elem+0x30/0x30 [ 44.822021] map_update_elem+0x605/0xf60 [ 44.826071] __x64_sys_bpf+0x32d/0x520 [ 44.829943] ? bpf_prog_get+0x20/0x20 [ 44.833740] do_syscall_64+0x1b9/0x820 [ 44.837614] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 44.842987] ? syscall_return_slowpath+0x5e0/0x5e0 [ 44.847901] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.852730] ? trace_hardirqs_on_caller+0x310/0x310 [ 44.857733] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 44.862734] ? prepare_exit_to_usermode+0x291/0x3b0 [ 44.867736] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.872598] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 44.877770] RIP: 0033:0x4400e9 [ 44.880953] 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 [ 44.899853] RSP: 002b:00007ffc639852a8 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 44.907557] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 44.914808] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 44.922062] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 44.929328] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 44.936601] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 44.943870] [ 44.945478] Allocated by task 6034: [ 44.949089] save_stack+0x43/0xd0 [ 44.952525] kasan_kmalloc+0xc7/0xe0 [ 44.956235] __kmalloc_node+0x50/0x70 [ 44.960015] bpf_map_area_alloc+0x3f/0x90 [ 44.964147] queue_stack_map_alloc+0x192/0x290 [ 44.968708] map_create+0x3bd/0x1110 [ 44.972443] __x64_sys_bpf+0x303/0x520 [ 44.976332] do_syscall_64+0x1b9/0x820 [ 44.980222] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 44.985390] [ 44.987030] Freed by task 3699: [ 44.990297] save_stack+0x43/0xd0 [ 44.993775] __kasan_slab_free+0x102/0x150 [ 44.998020] kasan_slab_free+0xe/0x10 [ 45.001802] kfree+0xcf/0x230 [ 45.004897] skb_free_head+0x99/0xc0 [ 45.008591] skb_release_data+0x6a4/0x880 [ 45.012723] skb_release_all+0x4a/0x60 [ 45.016592] consume_skb+0x1a9/0x560 [ 45.020290] skb_free_datagram+0x1a/0xf0 [ 45.024337] unix_dgram_recvmsg+0xd6d/0x1b10 [ 45.028734] sock_recvmsg+0xd0/0x110 [ 45.032432] __sys_recvfrom+0x311/0x5d0 [ 45.036389] __x64_sys_recvfrom+0xe1/0x1a0 [ 45.040606] do_syscall_64+0x1b9/0x820 [ 45.044476] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.049641] [ 45.051252] The buggy address belongs to the object at ffff8801c49465c0 [ 45.051252] which belongs to the cache kmalloc-512 of size 512 [ 45.063918] The buggy address is located 328 bytes inside of [ 45.063918] 512-byte region [ffff8801c49465c0, ffff8801c49467c0) [ 45.075774] The buggy address belongs to the page: [ 45.080685] page:ffffea0007125180 count:1 mapcount:0 mapping:ffff8801da800940 index:0xffff8801c4946d40 [ 45.090123] flags: 0x2fffc0000000200(slab) [ 45.094345] raw: 02fffc0000000200 ffffea0006da66c8 ffffea000718c208 ffff8801da800940 [ 45.102213] raw: ffff8801c4946d40 ffff8801c49460c0 0000000100000005 0000000000000000 [ 45.110073] page dumped because: kasan: bad access detected [ 45.115760] [ 45.117373] Memory state around the buggy address: [ 45.122301] ffff8801c4946600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 45.129644] ffff8801c4946680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 45.136987] >ffff8801c4946700: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc [ 45.144326] ^ [ 45.149759] ffff8801c4946780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 45.157102] ffff8801c4946800: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb [ 45.164440] ================================================================== [ 45.171780] Disabling lock debugging due to kernel taint [ 45.177208] Kernel panic - not syncing: panic_on_warn set ... [ 45.183075] CPU: 1 PID: 6034 Comm: syz-executor949 Tainted: G B 4.20.0-rc1-next-20181109+ #110 [ 45.193107] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.202440] Call Trace: [ 45.205011] dump_stack+0x244/0x39d [ 45.208621] ? dump_stack_print_info.cold.1+0x20/0x20 [ 45.213801] panic+0x2ad/0x55c [ 45.216983] ? add_taint.cold.5+0x16/0x16 [ 45.221119] ? add_taint.cold.5+0x5/0x16 [ 45.225166] ? trace_hardirqs_off+0xaf/0x310 [ 45.229574] kasan_end_report+0x47/0x4f [ 45.233530] kasan_report.cold.8+0x76/0x309 [ 45.237831] ? queue_stack_map_push_elem+0x185/0x290 [ 45.242932] check_memory_region+0x13e/0x1b0 [ 45.247323] memcpy+0x37/0x50 [ 45.250418] queue_stack_map_push_elem+0x185/0x290 [ 45.255331] ? queue_map_pop_elem+0x30/0x30 [ 45.259649] map_update_elem+0x605/0xf60 [ 45.263703] __x64_sys_bpf+0x32d/0x520 [ 45.267572] ? bpf_prog_get+0x20/0x20 [ 45.271368] do_syscall_64+0x1b9/0x820 [ 45.275241] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 45.280585] ? syscall_return_slowpath+0x5e0/0x5e0 [ 45.285495] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.290334] ? trace_hardirqs_on_caller+0x310/0x310 [ 45.295354] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 45.300357] ? prepare_exit_to_usermode+0x291/0x3b0 [ 45.305363] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 45.310192] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 45.315366] RIP: 0033:0x4400e9 [ 45.318543] 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 [ 45.337426] RSP: 002b:00007ffc639852a8 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 45.345117] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 45.352370] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 45.359626] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 45.367023] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 45.374273] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 45.382470] Kernel Offset: disabled [ 45.386090] Rebooting in 86400 seconds..