INIT: Entering runlevel: 2 [[36minfo[39;49m] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.13' (ECDSA) to the list of known hosts. 2018/04/06 03:43:31 parsed 1 programs 2018/04/06 03:43:31 executed programs: 0 syzkaller login: [ 24.142363] IPVS: Creating netns size=2536 id=1 [ 24.178640] IPVS: Creating netns size=2536 id=2 [ 24.200035] IPVS: Creating netns size=2536 id=3 [ 24.221341] IPVS: Creating netns size=2536 id=4 [ 24.244807] IPVS: Creating netns size=2536 id=5 [ 24.262278] IPVS: Creating netns size=2536 id=6 [ 24.285522] IPVS: Creating netns size=2536 id=7 RESULT: signal 0, coverage 0 errno 9 [ 24.313594] IPVS: Creating netns size=2536 id=8 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 RESULT: signal 0, coverage 0 errno 9 [ 24.693877] ================================================================== [ 24.701281] BUG: KASAN: use-after-free in __lock_acquire+0x319e/0x4080 [ 24.707926] Read of size 8 at addr ffff8801d976c4a0 by task syz-executor0/3864 [ 24.715252] [ 24.716860] CPU: 1 PID: 3864 Comm: syz-executor0 Not tainted 4.9.92-g7cd9561 #1 [ 24.724281] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.733606] ffff8801d8ee7610 ffffffff81d9c489 ffffea000765da00 ffff8801d976c4a0 [ 24.741589] 0000000000000000 ffff8801d976c4a0 0000000000000000 ffff8801d8ee7648 [ 24.749573] ffffffff8156556b ffff8801d976c4a0 0000000000000008 0000000000000000 [ 24.757535] Call Trace: [ 24.760093] [] dump_stack+0xc1/0x128 [ 24.765427] [] print_address_description+0x6c/0x234 [ 24.772062] [] kasan_report.cold.6+0xac/0x2f5 [ 24.778177] [] ? __lock_acquire+0x319e/0x4080 [ 24.784298] [] __asan_report_load8_noabort+0x14/0x20 [ 24.791038] [] __lock_acquire+0x319e/0x4080 [ 24.796984] [] ? __unwind_start+0x14d/0x3c0 [ 24.802928] [] ? unwind_next_frame+0x86/0xe0 [ 24.808959] [] ? debug_check_no_locks_freed+0x210/0x210 [ 24.815943] [] ? free_fs_struct+0x4f/0x60 [ 24.821713] [] ? save_stack+0xa9/0xd0 [ 24.827134] [] ? exit_fs+0xe9/0x120 [ 24.832720] [] ? do_exit+0x9bb/0x27c0 [ 24.838141] [] ? do_group_exit+0x111/0x340 [ 24.844001] [] ? get_signal+0x4cf/0x1450 [ 24.849684] [] ? do_signal+0x87/0x19f0 [ 24.855199] [] ? exit_to_usermode_loop+0xe1/0x120 [ 24.861667] [] ? do_fast_syscall_32+0x5c3/0x870 [ 24.867963] [] lock_acquire+0x130/0x3e0 [ 24.873558] [] ? lock_sock_nested+0x43/0x120 [ 24.879585] [] ? sock_release+0x1c0/0x1c0 [ 24.885349] [] _raw_spin_lock_bh+0x3a/0x50 [ 24.891203] [] ? lock_sock_nested+0x43/0x120 [ 24.897230] [] lock_sock_nested+0x43/0x120 [ 24.903083] [] pppol2tp_release+0x50/0x2e0 [ 24.908940] [] sock_release+0x96/0x1c0 [ 24.914455] [] sock_close+0x16/0x20 [ 24.919707] [] __fput+0x263/0x700 [ 24.924780] [] ____fput+0x15/0x20 [ 24.929855] [] task_work_run+0x10c/0x180 [ 24.935537] [] do_exit+0x9e1/0x27c0 [ 24.940788] [] ? debug_check_no_locks_freed+0x210/0x210 [ 24.947777] [] ? save_stack_trace+0x16/0x20 [ 24.953715] [] ? save_stack+0x43/0xd0 [ 24.959132] [] ? dentry_free+0xd5/0x150 [ 24.964726] [] ? release_task.part.19+0x1210/0x1210 [ 24.971362] [] ? exit_to_usermode_loop+0xfc/0x120 [ 24.977821] [] ? recalc_sigpending+0x72/0x90 [ 24.983851] [] do_group_exit+0x111/0x340 [ 24.989535] [] get_signal+0x4cf/0x1450 [ 24.995041] [] ? check_preemption_disabled+0x3b/0x170 [ 25.001855] [] do_signal+0x87/0x19f0 [ 25.007188] [] ? check_preemption_disabled+0x3b/0x170 [ 25.013998] [] ? mntput_no_expire+0xca/0x6b0 [ 25.020031] [] ? setup_sigcontext+0x7d0/0x7d0 [ 25.026154] [] ? sock_release+0x1c0/0x1c0 [ 25.031918] [] ? mntput_no_expire+0xf6/0x6b0 [ 25.037946] [] ? mnt_get_count+0x140/0x140 [ 25.043800] [] ? dput.part.29+0x16d/0x7b0 [ 25.049567] [] ? dput.part.29+0x2a/0x7b0 [ 25.055251] [] ? sock_release+0x1c0/0x1c0 [ 25.061017] [] ? mntput+0x66/0x90 [ 25.066092] [] ? exit_to_usermode_loop+0xac/0x120 [ 25.072551] [] exit_to_usermode_loop+0xe1/0x120 [ 25.078837] [] do_fast_syscall_32+0x5c3/0x870 [ 25.084952] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.091589] [] entry_SYSENTER_compat+0x90/0xa2 [ 25.097785] [ 25.099382] Allocated by task 3864: [ 25.102984] save_stack_trace+0x16/0x20 [ 25.106927] save_stack+0x43/0xd0 [ 25.110346] kasan_kmalloc+0xc7/0xe0 [ 25.114030] __kmalloc+0x11d/0x300 [ 25.117537] sk_prot_alloc+0x17e/0x290 [ 25.121394] sk_alloc+0x3a/0x3a0 [ 25.124727] pppol2tp_create+0x33/0x1f0 [ 25.128669] pppox_create+0xf6/0x210 [ 25.132350] __sock_create+0x2ef/0x5f0 [ 25.136203] SyS_socket+0xf0/0x1b0 [ 25.139719] do_fast_syscall_32+0x2f7/0x870 [ 25.144016] entry_SYSENTER_compat+0x90/0xa2 [ 25.148393] [ 25.149994] Freed by task 3864: [ 25.153241] save_stack_trace+0x16/0x20 [ 25.157185] save_stack+0x43/0xd0 [ 25.160609] kasan_slab_free+0x72/0xc0 [ 25.164482] kfree+0xfb/0x310 [ 25.167557] __sk_destruct+0x46f/0x590 [ 25.171413] sk_destruct+0x63/0x80 [ 25.174922] __sk_free+0x15e/0x220 [ 25.178428] sk_free+0x2b/0x40 [ 25.181589] pppol2tp_session_sock_put+0x5a/0x70 [ 25.186314] l2tp_tunnel_closeall+0x268/0x350 [ 25.190778] l2tp_udp_encap_destroy+0x87/0xe0 [ 25.195241] udpv6_destroy_sock+0xb1/0xd0 [ 25.199358] sk_common_release+0x6d/0x300 [ 25.203488] udp_lib_close+0x15/0x20 [ 25.207170] inet_release+0xff/0x1d0 [ 25.210854] inet6_release+0x50/0x70 [ 25.214539] sock_release+0x96/0x1c0 [ 25.218224] sock_close+0x16/0x20 [ 25.221654] __fput+0x263/0x700 [ 25.224995] ____fput+0x15/0x20 [ 25.228248] task_work_run+0x10c/0x180 [ 25.232105] exit_to_usermode_loop+0xfc/0x120 [ 25.236565] do_fast_syscall_32+0x5c3/0x870 [ 25.240857] entry_SYSENTER_compat+0x90/0xa2 [ 25.245231] [ 25.246828] The buggy address belongs to the object at ffff8801d976c400 [ 25.246828] which belongs to the cache kmalloc-2048 of size 2048 [ 25.259625] The buggy address is located 160 bytes inside of [ 25.259625] 2048-byte region [ffff8801d976c400, ffff8801d976cc00) [ 25.271550] The buggy address belongs to the page: [ 25.276453] page:ffffea000765da00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 25.286633] flags: 0x8000000000004080(slab|head) [ 25.291351] page dumped because: kasan: bad access detected [ 25.297026] [ 25.298622] Memory state around the buggy address: [ 25.303527] ffff8801d976c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 25.310859] ffff8801d976c400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.318188] >ffff8801d976c480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.325519] ^ [ 25.329904] ffff8801d976c500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.337235] ffff8801d976c580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 25.344561] ================================================================== [ 25.351896] Disabling lock debugging due to kernel taint [ 25.357318] Kernel panic - not syncing: panic_on_warn set ... [ 25.357318] [ 25.364656] CPU: 1 PID: 3864 Comm: syz-executor0 Tainted: G B 4.9.92-g7cd9561 #1 [ 25.373285] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.382607] ffff8801d8ee7570 ffffffff81d9c489 ffffffff841a85f1 00000000ffffffff [ 25.390573] 0000000000000000 0000000000000001 0000000000000000 ffff8801d8ee7630 [ 25.398547] ffffffff8141fa55 0000000041b58ab3 ffffffff8419bd28 ffffffff8141f896 [ 25.406509] Call Trace: [ 25.409072] [] dump_stack+0xc1/0x128 [ 25.414408] [] panic+0x1bf/0x3bc [ 25.419394] [] ? add_taint.cold.6+0x16/0x16 [ 25.425338] [] ? kasan_end_report+0x32/0x4f [ 25.431281] [] kasan_end_report+0x47/0x4f [ 25.437046] [] kasan_report.cold.6+0xc9/0x2f5 [ 25.443160] [] ? __lock_acquire+0x319e/0x4080 [ 25.449274] [] __asan_report_load8_noabort+0x14/0x20 [ 25.455996] [] __lock_acquire+0x319e/0x4080 [ 25.461944] [] ? __unwind_start+0x14d/0x3c0 [ 25.467888] [] ? unwind_next_frame+0x86/0xe0 [ 25.473924] [] ? debug_check_no_locks_freed+0x210/0x210 [ 25.480912] [] ? free_fs_struct+0x4f/0x60 [ 25.486680] [] ? save_stack+0xa9/0xd0 [ 25.492099] [] ? exit_fs+0xe9/0x120 [ 25.497355] [] ? do_exit+0x9bb/0x27c0 [ 25.502773] [] ? do_group_exit+0x111/0x340 [ 25.508631] [] ? get_signal+0x4cf/0x1450 [ 25.514309] [] ? do_signal+0x87/0x19f0 [ 25.519814] [] ? exit_to_usermode_loop+0xe1/0x120 [ 25.526274] [] ? do_fast_syscall_32+0x5c3/0x870 [ 25.532562] [] lock_acquire+0x130/0x3e0 [ 25.538157] [] ? lock_sock_nested+0x43/0x120 [ 25.544184] [] ? sock_release+0x1c0/0x1c0 [ 25.549950] [] _raw_spin_lock_bh+0x3a/0x50 [ 25.555801] [] ? lock_sock_nested+0x43/0x120 [ 25.561833] [] lock_sock_nested+0x43/0x120 [ 25.567688] [] pppol2tp_release+0x50/0x2e0 [ 25.573543] [] sock_release+0x96/0x1c0 [ 25.579050] [] sock_close+0x16/0x20 [ 25.584294] [] __fput+0x263/0x700 [ 25.589364] [] ____fput+0x15/0x20 [ 25.594439] [] task_work_run+0x10c/0x180 [ 25.600118] [] do_exit+0x9e1/0x27c0 [ 25.605364] [] ? debug_check_no_locks_freed+0x210/0x210 [ 25.612355] [] ? save_stack_trace+0x16/0x20 [ 25.618295] [] ? save_stack+0x43/0xd0 [ 25.623715] [] ? dentry_free+0xd5/0x150 [ 25.629312] [] ? release_task.part.19+0x1210/0x1210 [ 25.635955] [] ? exit_to_usermode_loop+0xfc/0x120 [ 25.642420] [] ? recalc_sigpending+0x72/0x90 [ 25.648448] [] do_group_exit+0x111/0x340 [ 25.654129] [] get_signal+0x4cf/0x1450 [ 25.659635] [] ? check_preemption_disabled+0x3b/0x170 [ 25.666444] [] do_signal+0x87/0x19f0 [ 25.671777] [] ? check_preemption_disabled+0x3b/0x170 [ 25.678583] [] ? mntput_no_expire+0xca/0x6b0 [ 25.684612] [] ? setup_sigcontext+0x7d0/0x7d0 [ 25.690725] [] ? sock_release+0x1c0/0x1c0 [ 25.696490] [] ? mntput_no_expire+0xf6/0x6b0 [ 25.702514] [] ? mnt_get_count+0x140/0x140 [ 25.708365] [] ? dput.part.29+0x16d/0x7b0 [ 25.714128] [] ? dput.part.29+0x2a/0x7b0 [ 25.719804] [] ? sock_release+0x1c0/0x1c0 [ 25.725566] [] ? mntput+0x66/0x90 [ 25.730647] [] ? exit_to_usermode_loop+0xac/0x120 [ 25.737104] [] exit_to_usermode_loop+0xe1/0x120 [ 25.743390] [] do_fast_syscall_32+0x5c3/0x870 [ 25.749502] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 25.756138] [] entry_SYSENTER_compat+0x90/0xa2 [ 25.762795] Dumping ftrace buffer: [ 25.766308] (ftrace buffer empty) [ 25.769985] Kernel Offset: disabled [ 25.773578] Rebooting in 86400 seconds..