INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] 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. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added 'ci-upstream-next-kasan-gce-2,10.128.0.56' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 52.639594] ================================================================== [ 52.640866] BUG: KASAN: double-free or invalid-free in selinux_tun_dev_free_security+0x15/0x20 [ 52.642120] [ 52.642352] CPU: 1 PID: 2937 Comm: syzkaller252960 Not tainted 4.13.0-rc4-next-20170811 #1 [ 52.643614] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.644983] Call Trace: [ 52.645407] dump_stack+0x194/0x257 [ 52.645907] ? arch_local_irq_restore+0x53/0x53 [ 52.646793] ? show_regs_print_info+0x65/0x65 [ 52.647471] ? mark_held_locks+0xaf/0x100 [ 52.648078] ? selinux_tun_dev_free_security+0x15/0x20 [ 52.648881] print_address_description+0x7f/0x260 [ 52.649543] ? selinux_tun_dev_free_security+0x15/0x20 [ 52.650253] ? selinux_tun_dev_free_security+0x15/0x20 [ 52.651010] kasan_report_double_free+0x55/0x80 [ 52.651706] kasan_slab_free+0xa0/0xc0 [ 52.652300] kfree+0xd3/0x260 [ 52.652723] selinux_tun_dev_free_security+0x15/0x20 [ 52.653501] security_tun_dev_free_security+0x48/0x80 [ 52.654387] __tun_chr_ioctl+0x2cb5/0x3d20 [ 52.655744] ? unwind_get_return_address+0x84/0xa0 [ 52.656782] ? tun_select_queue+0x580/0x580 [ 52.657493] ? putname+0xee/0x130 [ 52.658058] ? save_stack+0xa3/0xd0 [ 52.658739] ? save_stack_trace+0x16/0x20 [ 52.659307] ? save_stack+0x43/0xd0 [ 52.660294] ? kasan_slab_free+0x6e/0xc0 [ 52.664330] ? kmem_cache_free+0x71/0x240 [ 52.668446] ? putname+0xee/0x130 [ 52.671881] ? check_noncircular+0x20/0x20 [ 52.676095] ? __pmd_alloc+0x4f0/0x4f0 [ 52.680042] ? check_same_owner+0x320/0x320 [ 52.684331] ? lock_acquire+0x1d5/0x580 [ 52.688274] ? lock_acquire+0x1d5/0x580 [ 52.692237] ? tun_chr_compat_ioctl+0x30/0x30 [ 52.696699] tun_chr_ioctl+0x2a/0x40 [ 52.700380] ? tun_chr_ioctl+0x2a/0x40 [ 52.704237] do_vfs_ioctl+0x1b1/0x1520 [ 52.708105] ? _cond_resched+0x14/0x30 [ 52.711965] ? ioctl_preallocate+0x2b0/0x2b0 [ 52.716345] ? selinux_capable+0x40/0x40 [ 52.720386] ? __ioremap_caller+0xda/0x750 [ 52.724591] ? downgrade_write+0x150/0x150 [ 52.728806] ? security_file_ioctl+0x7d/0xb0 [ 52.733183] ? security_file_ioctl+0x89/0xb0 [ 52.737564] SyS_ioctl+0x8f/0xc0 [ 52.740904] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 52.745634] RIP: 0033:0x443eb9 [ 52.748790] RSP: 002b:00007ffc42ea9368 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ 52.756491] RAX: ffffffffffffffda RBX: 3ce0bf1bfd9aecc7 RCX: 0000000000443eb9 [ 52.764893] RDX: 0000000020533000 RSI: 00000000400454ca RDI: 0000000000000018 [ 52.772154] RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 [ 52.779425] R10: 0000000000000000 R11: 0000000000000217 R12: 0000001000003a8d [ 52.786695] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 52.793994] [ 52.795612] Allocated by task 2937: [ 52.799231] save_stack_trace+0x16/0x20 [ 52.803196] save_stack+0x43/0xd0 [ 52.806633] kasan_kmalloc+0xaa/0xd0 [ 52.810418] kmem_cache_alloc_trace+0x108/0x700 [ 52.815087] selinux_tun_dev_alloc_security+0x49/0x170 [ 52.820356] security_tun_dev_alloc_security+0x6d/0xa0 [ 52.825621] __tun_chr_ioctl+0x1730/0x3d20 [ 52.829850] tun_chr_ioctl+0x2a/0x40 [ 52.833552] do_vfs_ioctl+0x1b1/0x1520 [ 52.837421] SyS_ioctl+0x8f/0xc0 [ 52.840782] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 52.845522] [ 52.847129] Freed by task 2937: [ 52.850395] save_stack_trace+0x16/0x20 [ 52.854358] save_stack+0x43/0xd0 [ 52.857801] kasan_slab_free+0x6e/0xc0 [ 52.861682] kfree+0xd3/0x260 [ 52.864784] selinux_tun_dev_free_security+0x15/0x20 [ 52.869893] security_tun_dev_free_security+0x48/0x80 [ 52.875095] tun_free_netdev+0x13b/0x1b0 [ 52.879174] register_netdevice+0x92b/0xf40 [ 52.883597] __tun_chr_ioctl+0x1caf/0x3d20 [ 52.887863] tun_chr_ioctl+0x2a/0x40 [ 52.891585] do_vfs_ioctl+0x1b1/0x1520 [ 52.895470] SyS_ioctl+0x8f/0xc0 [ 52.898825] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 52.903596] [ 52.905211] The buggy address belongs to the object at ffff8801cd213440 [ 52.905211] which belongs to the cache kmalloc-32 of size 32 [ 52.917691] The buggy address is located 0 bytes inside of [ 52.917691] 32-byte region [ffff8801cd213440, ffff8801cd213460) [ 52.929541] The buggy address belongs to the page: [ 52.934456] page:ffffea00064df428 count:1 mapcount:0 mapping:ffff8801cd213000 index:0xffff8801cd213fc1 [ 52.943899] flags: 0x200000000000100(slab) [ 52.948115] raw: 0200000000000100 ffff8801cd213000 ffff8801cd213fc1 000000010000003f [ 52.956151] raw: ffffea000650b588 ffffea0006505cf0 ffff8801dbc00100 [ 52.962547] page dumped because: kasan: bad access detected [ 52.968251] [ 52.969850] Memory state around the buggy address: [ 52.974759] ffff8801cd213300: 00 00 00 fc fc fc fc fc 00 00 00 fc fc fc fc fc [ 52.982122] ffff8801cd213380: 00 00 00 fc fc fc fc fc fb fb fb fb fc fc fc fc [ 52.989477] >ffff8801cd213400: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc [ 52.996920] ^ [ 53.002358] ffff8801cd213480: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc [ 53.009715] ffff8801cd213500: fb fb fb fb fc fc fc fc fb fb fb fb fc fc fc fc [ 53.017147] ================================================================== [ 53.024486] Disabling lock debugging due to kernel taint [ 53.029932] Kernel panic - not syncing: panic_on_warn set ... [ 53.029932] [ 53.037454] CPU: 1 PID: 2937 Comm: syzkaller252960 Tainted: G B 4.13.0-rc4-next-20170811 #1 [ 53.047045] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.056380] Call Trace: [ 53.058961] dump_stack+0x194/0x257 [ 53.062576] ? arch_local_irq_restore+0x53/0x53 [ 53.067221] ? kasan_end_report+0x32/0x50 [ 53.071349] ? lock_downgrade+0x990/0x990 [ 53.075482] panic+0x1e4/0x417 [ 53.078657] ? __warn+0x1d9/0x1d9 [ 53.082187] ? selinux_tun_dev_free_security+0x15/0x20 [ 53.087582] ? selinux_tun_dev_free_security+0x15/0x20 [ 53.092835] kasan_end_report+0x50/0x50 [ 53.096794] kasan_report_double_free+0x72/0x80 [ 53.101443] kasan_slab_free+0xa0/0xc0 [ 53.105308] kfree+0xd3/0x260 [ 53.108390] selinux_tun_dev_free_security+0x15/0x20 [ 53.113472] security_tun_dev_free_security+0x48/0x80 [ 53.118653] __tun_chr_ioctl+0x2cb5/0x3d20 [ 53.122872] ? unwind_get_return_address+0x84/0xa0 [ 53.127966] ? tun_select_queue+0x580/0x580 [ 53.132271] ? putname+0xee/0x130 [ 53.135724] ? save_stack+0xa3/0xd0 [ 53.139352] ? save_stack_trace+0x16/0x20 [ 53.143478] ? save_stack+0x43/0xd0 [ 53.147088] ? kasan_slab_free+0x6e/0xc0 [ 53.151189] ? kmem_cache_free+0x71/0x240 [ 53.155311] ? putname+0xee/0x130 [ 53.158742] ? check_noncircular+0x20/0x20 [ 53.162955] ? __pmd_alloc+0x4f0/0x4f0 [ 53.166830] ? check_same_owner+0x320/0x320 [ 53.171130] ? lock_acquire+0x1d5/0x580 [ 53.175077] ? lock_acquire+0x1d5/0x580 [ 53.179042] ? tun_chr_compat_ioctl+0x30/0x30 [ 53.183616] tun_chr_ioctl+0x2a/0x40 [ 53.187306] ? tun_chr_ioctl+0x2a/0x40 [ 53.191356] do_vfs_ioctl+0x1b1/0x1520 [ 53.195223] ? _cond_resched+0x14/0x30 [ 53.199268] ? ioctl_preallocate+0x2b0/0x2b0 [ 53.203665] ? selinux_capable+0x40/0x40 [ 53.207728] ? __ioremap_caller+0xda/0x750 [ 53.211952] ? downgrade_write+0x150/0x150 [ 53.216170] ? security_file_ioctl+0x7d/0xb0 [ 53.220568] ? security_file_ioctl+0x89/0xb0 [ 53.225002] SyS_ioctl+0x8f/0xc0 [ 53.228365] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 53.233115] RIP: 0033:0x443eb9 [ 53.236286] RSP: 002b:00007ffc42ea9368 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ 53.243967] RAX: ffffffffffffffda RBX: 3ce0bf1bfd9aecc7 RCX: 0000000000443eb9 [ 53.251242] RDX: 0000000020533000 RSI: 00000000400454ca RDI: 0000000000000018 [ 53.258492] RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 [ 53.265745] R10: 0000000000000000 R11: 0000000000000217 R12: 0000001000003a8d [ 53.272995] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 53.280377] Dumping ftrace buffer: [ 53.283895] (ftrace buffer empty) [ 53.287659] Kernel Offset: disabled [ 53.291257] Rebooting in 86400 seconds..