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 'ci-upstream-kasan-gce-4,10.128.0.31' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 41.877652] ================================================================== [ 41.878868] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 [ 41.879791] Write of size 8 at addr ffff8801d13ab640 by task syzkaller615473/3004 [ 41.880834] [ 41.881105] CPU: 0 PID: 3004 Comm: syzkaller615473 Not tainted 4.13.0-rc7+ #64 [ 41.882135] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.883562] Call Trace: [ 41.883923] dump_stack+0x194/0x257 [ 41.884498] ? arch_local_irq_restore+0x53/0x53 [ 41.885226] ? show_regs_print_info+0x65/0x65 [ 41.885916] ? __kernel_text_address+0xae/0xe0 [ 41.886637] ? __internal_add_timer+0x275/0x2d0 [ 41.887401] print_address_description+0x73/0x250 [ 41.888138] ? __internal_add_timer+0x275/0x2d0 [ 41.888826] kasan_report+0x24e/0x340 [ 41.889419] __asan_report_store8_noabort+0x17/0x20 [ 41.890098] __internal_add_timer+0x275/0x2d0 [ 41.890752] ? calc_wheel_index+0x200/0x200 [ 41.891383] mod_timer+0x622/0x15b0 [ 41.891973] ? mod_timer_pending+0x14e0/0x14e0 [ 41.892624] ? __lock_is_held+0xb6/0x140 [ 41.893214] ? __lock_is_held+0xb6/0x140 [ 41.893852] ? lockdep_init_map+0xe4/0x650 [ 41.894551] ? init_timer_key+0x126/0x3b0 [ 41.895146] ? try_to_del_timer_sync+0x120/0x120 [ 41.895791] ? round_jiffies_up+0xce/0x100 [ 41.896467] ? __round_jiffies_up_relative+0x150/0x150 [ 41.897186] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 41.898247] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 41.903760] __tun_chr_ioctl+0x1b20/0x3d60 [ 41.907962] ? unwind_dump+0x4/0x4c0 [ 41.911654] ? tun_select_queue+0x580/0x580 [ 41.915945] ? check_noncircular+0x20/0x20 [ 41.920158] ? save_stack+0xa3/0xd0 [ 41.923760] ? __handle_mm_fault+0x577/0x3860 [ 41.928231] ? check_noncircular+0x20/0x20 [ 41.932544] ? check_noncircular+0x20/0x20 [ 41.936749] ? __pmd_alloc+0x4e0/0x4e0 [ 41.940633] ? check_same_owner+0x320/0x320 [ 41.944926] ? handle_mm_fault+0x23e/0x860 [ 41.949138] ? tun_chr_compat_ioctl+0x30/0x30 [ 41.953603] tun_chr_ioctl+0x2a/0x40 [ 41.957286] ? tun_chr_ioctl+0x2a/0x40 [ 41.961156] do_vfs_ioctl+0x1b1/0x1520 [ 41.965024] ? ioctl_preallocate+0x2b0/0x2b0 [ 41.969405] ? selinux_capable+0x40/0x40 [ 41.973442] ? __handle_mm_fault+0x3860/0x3860 [ 41.978035] ? security_file_ioctl+0x7d/0xb0 [ 41.982415] ? security_file_ioctl+0x89/0xb0 [ 41.986826] SyS_ioctl+0x8f/0xc0 [ 41.990172] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 41.994899] RIP: 0033:0x443d99 [ 41.998062] RSP: 002b:00007ffcffdd0b28 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 42.005738] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d99 [ 42.012977] RDX: 00000000207dcfd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 42.020215] RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 [ 42.027459] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401a80 [ 42.034698] R13: 0000000000401b10 R14: 0000000000000000 R15: 0000000000000000 [ 42.041980] [ 42.043587] Allocated by task 3004: [ 42.047187] save_stack_trace+0x16/0x20 [ 42.051128] save_stack+0x43/0xd0 [ 42.054560] kasan_kmalloc+0xad/0xe0 [ 42.058241] __kmalloc_node+0x47/0x70 [ 42.062010] kvmalloc_node+0x64/0xd0 [ 42.065691] alloc_netdev_mqs+0x16e/0xed0 [ 42.069817] __tun_chr_ioctl+0x12b2/0x3d60 [ 42.074036] tun_chr_ioctl+0x2a/0x40 [ 42.077718] do_vfs_ioctl+0x1b1/0x1520 [ 42.081571] SyS_ioctl+0x8f/0xc0 [ 42.084926] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.089654] [ 42.091250] Freed by task 3004: [ 42.094499] save_stack_trace+0x16/0x20 [ 42.098451] save_stack+0x43/0xd0 [ 42.101872] kasan_slab_free+0x71/0xc0 [ 42.105727] kfree+0xca/0x250 [ 42.108800] kvfree+0x36/0x60 [ 42.111873] free_netdev+0x2cf/0x360 [ 42.115567] __tun_chr_ioctl+0x2d24/0x3d60 [ 42.119769] tun_chr_ioctl+0x2a/0x40 [ 42.123449] do_vfs_ioctl+0x1b1/0x1520 [ 42.127305] SyS_ioctl+0x8f/0xc0 [ 42.130639] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.135359] [ 42.136957] The buggy address belongs to the object at ffff8801d13a8300 [ 42.136957] which belongs to the cache kmalloc-16384 of size 16384 [ 42.149936] The buggy address is located 13120 bytes inside of [ 42.149936] 16384-byte region [ffff8801d13a8300, ffff8801d13ac300) [ 42.162137] The buggy address belongs to the page: [ 42.167036] page:ffffea000744ea00 count:1 mapcount:0 mapping:ffff8801d13a8300 index:0x0 compound_mapcount: 0 [ 42.176975] flags: 0x200000000008100(slab|head) [ 42.181622] raw: 0200000000008100 ffff8801d13a8300 0000000000000000 0000000100000001 [ 42.189470] raw: ffffea00071d6220 ffffea0007447a20 ffff8801dac02200 0000000000000000 [ 42.197340] page dumped because: kasan: bad access detected [ 42.203028] [ 42.204622] Memory state around the buggy address: [ 42.209518] ffff8801d13ab500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.216882] ffff8801d13ab580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.224220] >ffff8801d13ab600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.231562] ^ [ 42.236977] ffff8801d13ab680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.244309] ffff8801d13ab700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.251640] ================================================================== [ 42.258970] Disabling lock debugging due to kernel taint [ 42.264386] Kernel panic - not syncing: panic_on_warn set ... [ 42.264386] [ 42.271714] CPU: 0 PID: 3004 Comm: syzkaller615473 Tainted: G B 4.13.0-rc7+ #64 [ 42.280252] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 42.289573] Call Trace: [ 42.292130] dump_stack+0x194/0x257 [ 42.295725] ? arch_local_irq_restore+0x53/0x53 [ 42.300377] ? kasan_end_report+0x32/0x50 [ 42.304493] ? lock_downgrade+0x990/0x990 [ 42.308621] ? __internal_add_timer+0x210/0x2d0 [ 42.313261] panic+0x1e4/0x417 [ 42.316420] ? __warn+0x1d9/0x1d9 [ 42.319845] ? __internal_add_timer+0x275/0x2d0 [ 42.324483] kasan_end_report+0x50/0x50 [ 42.328426] kasan_report+0x137/0x340 [ 42.332196] __asan_report_store8_noabort+0x17/0x20 [ 42.337179] __internal_add_timer+0x275/0x2d0 [ 42.341646] ? calc_wheel_index+0x200/0x200 [ 42.345941] mod_timer+0x622/0x15b0 [ 42.349551] ? mod_timer_pending+0x14e0/0x14e0 [ 42.354101] ? __lock_is_held+0xb6/0x140 [ 42.358168] ? __lock_is_held+0xb6/0x140 [ 42.362199] ? lockdep_init_map+0xe4/0x650 [ 42.366406] ? init_timer_key+0x126/0x3b0 [ 42.370524] ? try_to_del_timer_sync+0x120/0x120 [ 42.375250] ? round_jiffies_up+0xce/0x100 [ 42.379462] ? __round_jiffies_up_relative+0x150/0x150 [ 42.384708] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 42.389606] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 42.395118] __tun_chr_ioctl+0x1b20/0x3d60 [ 42.399324] ? unwind_dump+0x4/0x4c0 [ 42.403010] ? tun_select_queue+0x580/0x580 [ 42.407313] ? check_noncircular+0x20/0x20 [ 42.411527] ? save_stack+0xa3/0xd0 [ 42.415137] ? __handle_mm_fault+0x577/0x3860 [ 42.419609] ? check_noncircular+0x20/0x20 [ 42.423813] ? check_noncircular+0x20/0x20 [ 42.428027] ? __pmd_alloc+0x4e0/0x4e0 [ 42.431893] ? check_same_owner+0x320/0x320 [ 42.436186] ? handle_mm_fault+0x23e/0x860 [ 42.440405] ? tun_chr_compat_ioctl+0x30/0x30 [ 42.444868] tun_chr_ioctl+0x2a/0x40 [ 42.448550] ? tun_chr_ioctl+0x2a/0x40 [ 42.452408] do_vfs_ioctl+0x1b1/0x1520 [ 42.456268] ? ioctl_preallocate+0x2b0/0x2b0 [ 42.460642] ? selinux_capable+0x40/0x40 [ 42.464672] ? __handle_mm_fault+0x3860/0x3860 [ 42.469236] ? security_file_ioctl+0x7d/0xb0 [ 42.473611] ? security_file_ioctl+0x89/0xb0 [ 42.477995] SyS_ioctl+0x8f/0xc0 [ 42.481332] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.486051] RIP: 0033:0x443d99 [ 42.489205] RSP: 002b:00007ffcffdd0b28 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 42.496889] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d99 [ 42.504124] RDX: 00000000207dcfd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 42.511363] RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000 [ 42.518600] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401a80 [ 42.525846] R13: 0000000000401b10 R14: 0000000000000000 R15: 0000000000000000