[....] 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. [ 29.287882] kauditd_printk_skb: 8 callbacks suppressed [ 29.287897] audit: type=1800 audit(1543142293.622:29): pid=5918 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 [ 29.313341] audit: type=1800 audit(1543142293.632:30): pid=5918 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 '10.128.0.87' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 42.462721] ================================================================== [ 42.470268] BUG: KASAN: slab-out-of-bounds in queue_stack_map_push_elem+0x185/0x290 [ 42.478088] Write of size 262146 at addr ffff8881bd6a1bc8 by task syz-executor819/6075 [ 42.486224] [ 42.487842] CPU: 1 PID: 6075 Comm: syz-executor819 Not tainted 4.20.0-rc3+ #313 [ 42.495268] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.504630] Call Trace: [ 42.507210] dump_stack+0x244/0x39d [ 42.510954] ? dump_stack_print_info.cold.1+0x20/0x20 [ 42.516252] ? printk+0xa7/0xcf [ 42.519549] ? kmsg_dump_rewind_nolock+0xe4/0xe4 [ 42.524311] print_address_description.cold.7+0x9/0x1ff [ 42.529690] kasan_report.cold.8+0x242/0x309 [ 42.534206] ? queue_stack_map_push_elem+0x185/0x290 [ 42.539393] check_memory_region+0x13e/0x1b0 [ 42.543808] memcpy+0x37/0x50 [ 42.546906] queue_stack_map_push_elem+0x185/0x290 [ 42.551843] ? queue_map_pop_elem+0x30/0x30 [ 42.556150] map_update_elem+0x605/0xf60 [ 42.560210] __x64_sys_bpf+0x32d/0x520 [ 42.564086] ? bpf_prog_get+0x20/0x20 [ 42.568004] do_syscall_64+0x1b9/0x820 [ 42.571885] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 42.577237] ? syscall_return_slowpath+0x5e0/0x5e0 [ 42.582163] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.586999] ? trace_hardirqs_on_caller+0x310/0x310 [ 42.592002] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 42.597019] ? prepare_exit_to_usermode+0x291/0x3b0 [ 42.602024] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 42.607024] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.612205] RIP: 0033:0x4400e9 [ 42.615408] 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 [ 42.634584] RSP: 002b:00007ffd052c9c38 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 42.642508] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 42.649772] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 42.657035] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 42.664297] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 42.671558] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 42.678834] [ 42.680597] Allocated by task 6075: [ 42.684218] save_stack+0x43/0xd0 [ 42.687680] kasan_kmalloc+0xc7/0xe0 [ 42.691504] __kmalloc_node+0x50/0x70 [ 42.695292] bpf_map_area_alloc+0x3f/0x90 [ 42.699443] queue_stack_map_alloc+0x192/0x290 [ 42.704013] map_create+0x3bd/0x1110 [ 42.707709] __x64_sys_bpf+0x303/0x520 [ 42.711814] do_syscall_64+0x1b9/0x820 [ 42.715750] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.721162] [ 42.722897] Freed by task 3715: [ 42.726175] save_stack+0x43/0xd0 [ 42.729615] __kasan_slab_free+0x102/0x150 [ 42.733863] kasan_slab_free+0xe/0x10 [ 42.737774] kfree+0xcf/0x230 [ 42.740868] kernfs_fop_release+0x12b/0x1a0 [ 42.745189] __fput+0x385/0xa30 [ 42.748458] ____fput+0x15/0x20 [ 42.751758] task_work_run+0x1e8/0x2a0 [ 42.755651] exit_to_usermode_loop+0x318/0x380 [ 42.760285] do_syscall_64+0x6be/0x820 [ 42.764239] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 42.769429] [ 42.771061] The buggy address belongs to the object at ffff8881bd6a1a80 [ 42.771061] which belongs to the cache kmalloc-512 of size 512 [ 42.783912] The buggy address is located 328 bytes inside of [ 42.783912] 512-byte region [ffff8881bd6a1a80, ffff8881bd6a1c80) [ 42.795842] The buggy address belongs to the page: [ 42.800916] page:ffffea0006f5a840 count:1 mapcount:0 mapping:ffff8881da800940 index:0x0 [ 42.809052] flags: 0x2fffc0000000200(slab) [ 42.813276] raw: 02fffc0000000200 ffffea0006f58e88 ffffea0006f40e88 ffff8881da800940 [ 42.821147] raw: 0000000000000000 ffff8881bd6a1080 0000000100000006 0000000000000000 [ 42.829014] page dumped because: kasan: bad access detected [ 42.834855] [ 42.836464] Memory state around the buggy address: [ 42.841410] ffff8881bd6a1b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.848876] ffff8881bd6a1b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.856223] >ffff8881bd6a1c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.863788] ^ [ 42.867186] ffff8881bd6a1c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.874536] ffff8881bd6a1d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.881877] ================================================================== [ 42.889230] Disabling lock debugging due to kernel taint [ 42.894662] Kernel panic - not syncing: panic_on_warn set ... [ 42.900652] CPU: 1 PID: 6075 Comm: syz-executor819 Tainted: G B 4.20.0-rc3+ #313 [ 42.909591] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.919130] Call Trace: [ 42.921835] dump_stack+0x244/0x39d [ 42.925459] ? dump_stack_print_info.cold.1+0x20/0x20 [ 42.930639] panic+0x2ad/0x55c [ 42.933823] ? add_taint.cold.5+0x16/0x16 [ 42.937956] ? add_taint.cold.5+0x5/0x16 [ 42.942011] ? trace_hardirqs_off+0xaf/0x310 [ 42.946554] kasan_end_report+0x47/0x4f [ 42.950528] kasan_report.cold.8+0x76/0x309 [ 42.954840] ? queue_stack_map_push_elem+0x185/0x290 [ 42.959934] check_memory_region+0x13e/0x1b0 [ 42.964331] memcpy+0x37/0x50 [ 42.967503] queue_stack_map_push_elem+0x185/0x290 [ 42.972442] ? queue_map_pop_elem+0x30/0x30 [ 42.976843] map_update_elem+0x605/0xf60 [ 42.980898] __x64_sys_bpf+0x32d/0x520 [ 42.984782] ? bpf_prog_get+0x20/0x20 [ 42.988580] do_syscall_64+0x1b9/0x820 [ 42.992456] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 42.997940] ? syscall_return_slowpath+0x5e0/0x5e0 [ 43.002997] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.007931] ? trace_hardirqs_on_caller+0x310/0x310 [ 43.012934] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 43.017930] ? prepare_exit_to_usermode+0x291/0x3b0 [ 43.022960] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 43.027785] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 43.032957] RIP: 0033:0x4400e9 [ 43.036134] 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 [ 43.055146] RSP: 002b:00007ffd052c9c38 EFLAGS: 00000213 ORIG_RAX: 0000000000000141 [ 43.062849] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400e9 [ 43.070108] RDX: 0000000000000020 RSI: 0000000020000040 RDI: 0000000000000002 [ 43.077360] RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 [ 43.084661] R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401970 [ 43.091953] R13: 0000000000401a00 R14: 0000000000000000 R15: 0000000000000000 [ 43.100218] Kernel Offset: disabled [ 43.103860] Rebooting in 86400 seconds..