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-6,10.128.0.9' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 83.896583] ================================================================== [ 83.904014] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 [ 83.911006] Write of size 8 at addr ffff8801cc7ab6c8 by task syzkaller117030/3039 [ 83.918600] [ 83.920200] CPU: 1 PID: 3039 Comm: syzkaller117030 Not tainted 4.13.0+ #70 [ 83.927179] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 83.936502] Call Trace: [ 83.939060] dump_stack+0x194/0x257 [ 83.942667] ? arch_local_irq_restore+0x53/0x53 [ 83.947307] ? show_regs_print_info+0x65/0x65 [ 83.951790] ? __internal_add_timer+0x275/0x2d0 [ 83.956457] print_address_description+0x73/0x250 [ 83.961274] ? __internal_add_timer+0x275/0x2d0 [ 83.965928] kasan_report+0x24e/0x340 [ 83.969704] __asan_report_store8_noabort+0x17/0x20 [ 83.974687] __internal_add_timer+0x275/0x2d0 [ 83.979159] ? calc_wheel_index+0x200/0x200 [ 83.983460] mod_timer+0x622/0x15b0 [ 83.987064] ? mod_timer_pending+0x14e0/0x14e0 [ 83.991620] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 83.996606] ? trace_hardirqs_on+0xd/0x10 [ 84.000726] ? _crng_backtrack_protect+0xd9/0x130 [ 84.005545] ? __lock_is_held+0xbc/0x140 [ 84.009579] ? __lockdep_init_map+0xe4/0x650 [ 84.013958] ? lockdep_init_map+0x3d/0x70 [ 84.018084] ? rcu_read_lock_sched_held+0x108/0x120 [ 84.023077] ? init_timer_key+0x126/0x3b0 [ 84.027198] ? try_to_del_timer_sync+0x120/0x120 [ 84.031933] ? round_jiffies_up+0xce/0x100 [ 84.036136] ? __round_jiffies_up_relative+0x150/0x150 [ 84.041382] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 84.046403] __tun_chr_ioctl+0x1b2c/0x3d70 [ 84.050618] ? tun_select_queue+0x580/0x580 [ 84.054918] ? lock_downgrade+0x990/0x990 [ 84.059065] ? check_same_owner+0x320/0x320 [ 84.063369] ? __handle_mm_fault+0x3840/0x3840 [ 84.067922] ? vmacache_find+0x61/0x270 [ 84.071880] ? tun_chr_compat_ioctl+0x30/0x30 [ 84.076351] tun_chr_ioctl+0x2a/0x40 [ 84.080056] ? tun_chr_ioctl+0x2a/0x40 [ 84.083912] do_vfs_ioctl+0x1b1/0x1530 [ 84.087772] ? ioctl_preallocate+0x2b0/0x2b0 [ 84.092159] ? selinux_capable+0x40/0x40 [ 84.096194] ? putname+0xf3/0x130 [ 84.099618] ? do_sys_open+0x320/0x6d0 [ 84.103496] ? security_file_ioctl+0x7d/0xb0 [ 84.107878] ? security_file_ioctl+0x89/0xb0 [ 84.112259] SyS_ioctl+0x8f/0xc0 [ 84.115615] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 84.120337] RIP: 0033:0x443db9 [ 84.123511] RSP: 002b:00007fff83d682f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 84.131186] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443db9 [ 84.138427] RDX: 0000000020f14fd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 84.145666] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 84.152905] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401aa0 [ 84.160145] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 84.167402] [ 84.168999] Allocated by task 3039: [ 84.172595] save_stack_trace+0x16/0x20 [ 84.176556] save_stack+0x43/0xd0 [ 84.179981] kasan_kmalloc+0xad/0xe0 [ 84.183668] __kmalloc_node+0x47/0x70 [ 84.187461] kvmalloc_node+0x64/0xd0 [ 84.191147] alloc_netdev_mqs+0x16e/0xed0 [ 84.195265] __tun_chr_ioctl+0x12be/0x3d70 [ 84.199469] tun_chr_ioctl+0x2a/0x40 [ 84.203150] do_vfs_ioctl+0x1b1/0x1530 [ 84.207004] SyS_ioctl+0x8f/0xc0 [ 84.210351] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 84.215072] [ 84.216666] Freed by task 3039: [ 84.219914] save_stack_trace+0x16/0x20 [ 84.223858] save_stack+0x43/0xd0 [ 84.227294] kasan_slab_free+0x71/0xc0 [ 84.231148] kfree+0xca/0x250 [ 84.234221] kvfree+0x36/0x60 [ 84.237297] free_netdev+0x2cf/0x360 [ 84.241002] __tun_chr_ioctl+0x2d30/0x3d70 [ 84.245202] tun_chr_ioctl+0x2a/0x40 [ 84.248881] do_vfs_ioctl+0x1b1/0x1530 [ 84.252731] SyS_ioctl+0x8f/0xc0 [ 84.256062] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 84.260779] [ 84.262377] The buggy address belongs to the object at ffff8801cc7a82c0 [ 84.262377] which belongs to the cache kmalloc-16384 of size 16384 [ 84.275355] The buggy address is located 13320 bytes inside of [ 84.275355] 16384-byte region [ffff8801cc7a82c0, ffff8801cc7ac2c0) [ 84.287542] The buggy address belongs to the page: [ 84.292442] page:ffffea000731ea00 count:1 mapcount:0 mapping:ffff8801cc7a82c0 index:0x0 compound_mapcount: 0 [ 84.302386] flags: 0x200000000008100(slab|head) [ 84.307038] raw: 0200000000008100 ffff8801cc7a82c0 0000000000000000 0000000100000001 [ 84.314885] raw: ffffea00074f2220 ffffea000731e420 ffff8801dac02200 0000000000000000 [ 84.322733] page dumped because: kasan: bad access detected [ 84.328409] [ 84.330019] Memory state around the buggy address: [ 84.334922] ffff8801cc7ab580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 84.342293] ffff8801cc7ab600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 84.349618] >ffff8801cc7ab680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 84.356947] ^ [ 84.362624] ffff8801cc7ab700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 84.369949] ffff8801cc7ab780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 84.377271] ================================================================== [ 84.384598] Disabling lock debugging due to kernel taint [ 84.390009] Kernel panic - not syncing: panic_on_warn set ... [ 84.390009] [ 84.397390] CPU: 1 PID: 3039 Comm: syzkaller117030 Tainted: G B 4.13.0+ #70 [ 84.405591] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 84.414906] Call Trace: [ 84.417459] dump_stack+0x194/0x257 [ 84.421066] ? arch_local_irq_restore+0x53/0x53 [ 84.425709] ? vprintk_default+0x28/0x30 [ 84.429743] ? __internal_add_timer+0x1a0/0x2d0 [ 84.434381] panic+0x1e4/0x417 [ 84.437537] ? __warn+0x1d9/0x1d9 [ 84.440958] ? __internal_add_timer+0x275/0x2d0 [ 84.445589] kasan_end_report+0x50/0x50 [ 84.449565] kasan_report+0x137/0x340 [ 84.453332] __asan_report_store8_noabort+0x17/0x20 [ 84.458310] __internal_add_timer+0x275/0x2d0 [ 84.462765] ? calc_wheel_index+0x200/0x200 [ 84.467054] mod_timer+0x622/0x15b0 [ 84.470648] ? mod_timer_pending+0x14e0/0x14e0 [ 84.475191] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 84.480178] ? trace_hardirqs_on+0xd/0x10 [ 84.484333] ? _crng_backtrack_protect+0xd9/0x130 [ 84.489141] ? __lock_is_held+0xbc/0x140 [ 84.493165] ? __lockdep_init_map+0xe4/0x650 [ 84.497559] ? lockdep_init_map+0x3d/0x70 [ 84.501672] ? rcu_read_lock_sched_held+0x108/0x120 [ 84.506654] ? init_timer_key+0x126/0x3b0 [ 84.510785] ? try_to_del_timer_sync+0x120/0x120 [ 84.515505] ? round_jiffies_up+0xce/0x100 [ 84.519704] ? __round_jiffies_up_relative+0x150/0x150 [ 84.524966] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 84.529884] __tun_chr_ioctl+0x1b2c/0x3d70 [ 84.534090] ? tun_select_queue+0x580/0x580 [ 84.538383] ? lock_downgrade+0x990/0x990 [ 84.542506] ? check_same_owner+0x320/0x320 [ 84.546807] ? __handle_mm_fault+0x3840/0x3840 [ 84.551350] ? vmacache_find+0x61/0x270 [ 84.555287] ? tun_chr_compat_ioctl+0x30/0x30 [ 84.559751] tun_chr_ioctl+0x2a/0x40 [ 84.563427] ? tun_chr_ioctl+0x2a/0x40 [ 84.567277] do_vfs_ioctl+0x1b1/0x1530 [ 84.571128] ? ioctl_preallocate+0x2b0/0x2b0 [ 84.575504] ? selinux_capable+0x40/0x40 [ 84.579531] ? putname+0xf3/0x130 [ 84.582944] ? do_sys_open+0x320/0x6d0 [ 84.586794] ? security_file_ioctl+0x7d/0xb0 [ 84.591161] ? security_file_ioctl+0x89/0xb0 [ 84.595562] SyS_ioctl+0x8f/0xc0 [ 84.598893] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 84.603607] RIP: 0033:0x443db9 [ 84.606772] RSP: 002b:00007fff83d682f8 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 84.614445] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443db9 [ 84.621677] RDX: 0000000020f14fd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 84.628909] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 84.636203] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401aa0 [ 84.643460] R13: 0000000000401b30 R14: 0000000000000000 R15: 0000000000000000 [ 84.651054] Dumping ftrace buffer: [ 84.654561] (ftrace buffer empty) [ 84.658247] Kernel Offset: disabled [ 84.661838] Rebooting in 86400 seconds..