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-6,10.128.0.33' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 31.537091] ================================================================== [ 31.544533] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 [ 31.551517] Write of size 8 at addr ffff8801ce0f36c8 by task syzkaller204603/2982 [ 31.559109] [ 31.560711] CPU: 1 PID: 2982 Comm: syzkaller204603 Not tainted 4.13.0-next-20170905+ #15 [ 31.568907] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 31.578230] Call Trace: [ 31.580794] dump_stack+0x194/0x257 [ 31.584404] ? arch_local_irq_restore+0x53/0x53 [ 31.589048] ? show_regs_print_info+0x65/0x65 [ 31.593522] ? __internal_add_timer+0x275/0x2d0 [ 31.598166] print_address_description+0x73/0x250 [ 31.602981] ? __internal_add_timer+0x275/0x2d0 [ 31.607624] kasan_report+0x24e/0x340 [ 31.611404] __asan_report_store8_noabort+0x17/0x20 [ 31.616407] __internal_add_timer+0x275/0x2d0 [ 31.620878] ? calc_wheel_index+0x200/0x200 [ 31.625188] mod_timer+0x622/0x15b0 [ 31.628796] ? mod_timer_pending+0x14e0/0x14e0 [ 31.633349] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 31.638342] ? trace_hardirqs_on+0xd/0x10 [ 31.642517] ? _crng_backtrack_protect+0xd9/0x130 [ 31.647354] ? __lock_is_held+0xbc/0x140 [ 31.651403] ? __lockdep_init_map+0xe4/0x650 [ 31.655789] ? lockdep_init_map+0x3d/0x70 [ 31.659911] ? rcu_read_lock_sched_held+0x108/0x120 [ 31.664901] ? init_timer_key+0x126/0x3b0 [ 31.669032] ? try_to_del_timer_sync+0x120/0x120 [ 31.673762] ? round_jiffies_up+0xce/0x100 [ 31.677972] ? __round_jiffies_up_relative+0x150/0x150 [ 31.683220] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 31.688133] __tun_chr_ioctl+0x1b23/0x3d20 [ 31.692349] ? tun_chr_read_iter+0x1e0/0x1e0 [ 31.696738] ? lock_downgrade+0x990/0x990 [ 31.700883] ? check_same_owner+0x320/0x320 [ 31.705177] ? __handle_mm_fault+0x39c0/0x39c0 [ 31.709728] ? vmacache_find+0x61/0x270 [ 31.713679] ? tun_chr_compat_ioctl+0x30/0x30 [ 31.718146] tun_chr_ioctl+0x2a/0x40 [ 31.721830] ? tun_chr_ioctl+0x2a/0x40 [ 31.725691] do_vfs_ioctl+0x1b1/0x1530 [ 31.729557] ? ioctl_preallocate+0x2b0/0x2b0 [ 31.733943] ? selinux_capable+0x40/0x40 [ 31.737977] ? putname+0xf3/0x130 [ 31.741414] ? do_sys_open+0x320/0x6d0 [ 31.745284] ? security_file_ioctl+0x7d/0xb0 [ 31.749661] ? security_file_ioctl+0x89/0xb0 [ 31.754044] SyS_ioctl+0x8f/0xc0 [ 31.757402] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 31.762129] RIP: 0033:0x443d99 [ 31.765289] RSP: 002b:00007fff16f68ec8 EFLAGS: 00000207 ORIG_RAX: 0000000000000010 [ 31.772978] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d99 [ 31.780225] RDX: 0000000020822000 RSI: 00000000400454ca RDI: 0000000000000006 [ 31.787466] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 31.794715] R10: 0000000000000000 R11: 0000000000000207 R12: 5f6010a0d3dd9153 [ 31.801958] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 31.809219] [ 31.810820] Allocated by task 2982: [ 31.814424] save_stack_trace+0x16/0x20 [ 31.818377] save_stack+0x43/0xd0 [ 31.821804] kasan_kmalloc+0xad/0xe0 [ 31.826081] __kmalloc_node+0x47/0x70 [ 31.829855] kvmalloc_node+0x64/0xd0 [ 31.833550] alloc_netdev_mqs+0x16e/0xed0 [ 31.837668] __tun_chr_ioctl+0x12be/0x3d20 [ 31.841876] tun_chr_ioctl+0x2a/0x40 [ 31.845560] do_vfs_ioctl+0x1b1/0x1530 [ 31.849419] SyS_ioctl+0x8f/0xc0 [ 31.852757] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 31.857491] [ 31.859091] Freed by task 2982: [ 31.862343] save_stack_trace+0x16/0x20 [ 31.866299] save_stack+0x43/0xd0 [ 31.869723] kasan_slab_free+0x71/0xc0 [ 31.873580] kfree+0xca/0x250 [ 31.876655] kvfree+0x36/0x60 [ 31.879728] free_netdev+0x2cf/0x360 [ 31.883416] __tun_chr_ioctl+0x2cf6/0x3d20 [ 31.887619] tun_chr_ioctl+0x2a/0x40 [ 31.891302] do_vfs_ioctl+0x1b1/0x1530 [ 31.895167] SyS_ioctl+0x8f/0xc0 [ 31.898506] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 31.903228] [ 31.904827] The buggy address belongs to the object at ffff8801ce0f02c0 [ 31.904827] which belongs to the cache kmalloc-16384 of size 16384 [ 31.917799] The buggy address is located 13320 bytes inside of [ 31.917799] 16384-byte region [ffff8801ce0f02c0, ffff8801ce0f42c0) [ 31.929989] The buggy address belongs to the page: [ 31.934888] page:ffffea0007383c00 count:1 mapcount:0 mapping:ffff8801ce0f02c0 index:0x0 compound_mapcount: 0 [ 31.944835] flags: 0x200000000008100(slab|head) [ 31.949478] raw: 0200000000008100 ffff8801ce0f02c0 0000000000000000 0000000100000001 [ 31.957329] raw: ffffea000756e820 ffffea00073a0e20 ffff8801dac02200 0000000000000000 [ 31.965179] page dumped because: kasan: bad access detected [ 31.970869] [ 31.972469] Memory state around the buggy address: [ 31.977368] ffff8801ce0f3580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.984700] ffff8801ce0f3600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.992030] >ffff8801ce0f3680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 31.999359] ^ [ 32.005053] ffff8801ce0f3700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.012384] ffff8801ce0f3780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.019722] ================================================================== [ 32.027050] Disabling lock debugging due to kernel taint [ 32.032463] Kernel panic - not syncing: panic_on_warn set ... [ 32.032463] [ 32.039792] CPU: 1 PID: 2982 Comm: syzkaller204603 Tainted: G B 4.13.0-next-20170905+ #15 [ 32.049200] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.058518] Call Trace: [ 32.061077] dump_stack+0x194/0x257 [ 32.064672] ? arch_local_irq_restore+0x53/0x53 [ 32.069308] ? vprintk_default+0x28/0x30 [ 32.073338] ? __internal_add_timer+0x1e0/0x2d0 [ 32.077974] panic+0x1e4/0x417 [ 32.081129] ? __warn+0x1d9/0x1d9 [ 32.084555] ? __internal_add_timer+0x275/0x2d0 [ 32.089193] kasan_end_report+0x50/0x50 [ 32.093130] kasan_report+0x137/0x340 [ 32.096898] __asan_report_store8_noabort+0x17/0x20 [ 32.101878] __internal_add_timer+0x275/0x2d0 [ 32.106337] ? calc_wheel_index+0x200/0x200 [ 32.110629] mod_timer+0x622/0x15b0 [ 32.114227] ? mod_timer_pending+0x14e0/0x14e0 [ 32.118773] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.123754] ? trace_hardirqs_on+0xd/0x10 [ 32.127870] ? _crng_backtrack_protect+0xd9/0x130 [ 32.132679] ? __lock_is_held+0xbc/0x140 [ 32.136705] ? __lockdep_init_map+0xe4/0x650 [ 32.141080] ? lockdep_init_map+0x3d/0x70 [ 32.145193] ? rcu_read_lock_sched_held+0x108/0x120 [ 32.150173] ? init_timer_key+0x126/0x3b0 [ 32.154287] ? try_to_del_timer_sync+0x120/0x120 [ 32.159008] ? round_jiffies_up+0xce/0x100 [ 32.163208] ? __round_jiffies_up_relative+0x150/0x150 [ 32.168449] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 32.173347] __tun_chr_ioctl+0x1b23/0x3d20 [ 32.177550] ? tun_chr_read_iter+0x1e0/0x1e0 [ 32.181928] ? lock_downgrade+0x990/0x990 [ 32.186238] ? check_same_owner+0x320/0x320 [ 32.190525] ? __handle_mm_fault+0x39c0/0x39c0 [ 32.195070] ? vmacache_find+0x61/0x270 [ 32.199010] ? tun_chr_compat_ioctl+0x30/0x30 [ 32.203468] tun_chr_ioctl+0x2a/0x40 [ 32.207144] ? tun_chr_ioctl+0x2a/0x40 [ 32.210998] do_vfs_ioctl+0x1b1/0x1530 [ 32.214852] ? ioctl_preallocate+0x2b0/0x2b0 [ 32.219230] ? selinux_capable+0x40/0x40 [ 32.223257] ? putname+0xf3/0x130 [ 32.226680] ? do_sys_open+0x320/0x6d0 [ 32.230546] ? security_file_ioctl+0x7d/0xb0 [ 32.234918] ? security_file_ioctl+0x89/0xb0 [ 32.239292] SyS_ioctl+0x8f/0xc0 [ 32.242633] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 32.247364] RIP: 0033:0x443d99 [ 32.250535] RSP: 002b:00007fff16f68ec8 EFLAGS: 00000207 ORIG_RAX: 0000000000000010 [ 32.258209] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d99 [ 32.265445] RDX: 0000000020822000 RSI: 00000000400454ca RDI: 0000000000000006 [ 32.272679] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 32.279914] R10: 0000000000000000 R11: 0000000000000207 R12: 5f6010a0d3dd9153 [ 32.287150] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 32.294447] Dumping ftrace buffer: [ 32.297953] (ftrace buffer empty) [ 32.301630] Kernel Offset: disabled [ 32.305226] Rebooting in 86400 seconds..