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-kasan-gce-4,10.128.15.209' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 48.283312] ================================================================== [ 48.290753] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 [ 48.297762] Write of size 8 at addr ffff8801cc46b6c8 by task syzkaller884634/3041 [ 48.305394] [ 48.307009] CPU: 1 PID: 3041 Comm: syzkaller884634 Not tainted 4.13.0+ #70 [ 48.314005] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.323361] Call Trace: [ 48.325941] dump_stack+0x194/0x257 [ 48.329574] ? arch_local_irq_restore+0x53/0x53 [ 48.334243] ? show_regs_print_info+0x65/0x65 [ 48.338765] ? __kernel_text_address+0xae/0xe0 [ 48.343754] ? __internal_add_timer+0x275/0x2d0 [ 48.348452] print_address_description+0x73/0x250 [ 48.353290] ? __internal_add_timer+0x275/0x2d0 [ 48.357996] kasan_report+0x24e/0x340 [ 48.361797] __asan_report_store8_noabort+0x17/0x20 [ 48.366841] __internal_add_timer+0x275/0x2d0 [ 48.371334] ? calc_wheel_index+0x200/0x200 [ 48.375837] mod_timer+0x622/0x15b0 [ 48.379497] ? mod_timer_pending+0x14e0/0x14e0 [ 48.384106] ? __lock_is_held+0xbc/0x140 [ 48.388195] ? __lock_is_held+0xbc/0x140 [ 48.392267] ? __lockdep_init_map+0xe4/0x650 [ 48.396687] ? lockdep_init_map+0x3d/0x70 [ 48.400845] ? rcu_read_lock_sched_held+0x108/0x120 [ 48.405898] ? init_timer_key+0x126/0x3b0 [ 48.410052] ? try_to_del_timer_sync+0x120/0x120 [ 48.414822] ? round_jiffies_up+0xce/0x100 [ 48.419053] ? __round_jiffies_up_relative+0x150/0x150 [ 48.424394] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 48.429324] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 48.434911] __tun_chr_ioctl+0x1b2c/0x3d70 [ 48.439156] ? tun_select_queue+0x580/0x580 [ 48.443982] ? lock_downgrade+0x990/0x990 [ 48.448157] ? check_same_owner+0x320/0x320 [ 48.452477] ? __handle_mm_fault+0x3840/0x3840 [ 48.457062] ? vmacache_find+0x61/0x270 [ 48.461127] ? tun_chr_compat_ioctl+0x30/0x30 [ 48.465667] tun_chr_ioctl+0x2a/0x40 [ 48.469412] ? tun_chr_ioctl+0x2a/0x40 [ 48.473296] do_vfs_ioctl+0x1b1/0x1530 [ 48.477196] ? ioctl_preallocate+0x2b0/0x2b0 [ 48.481605] ? selinux_capable+0x40/0x40 [ 48.485665] ? putname+0xf3/0x130 [ 48.489173] ? do_sys_open+0x320/0x6d0 [ 48.493123] ? security_file_ioctl+0x7d/0xb0 [ 48.497527] ? security_file_ioctl+0x89/0xb0 [ 48.501977] SyS_ioctl+0x8f/0xc0 [ 48.505391] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 48.510176] RIP: 0033:0x443db9 [ 48.513364] RSP: 002b:00007fff43f5a4d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [ 48.521118] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443db9 [ 48.528424] RDX: 0000000020c12000 RSI: 00000000400454ca RDI: 0000000000000004 [ 48.535881] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 48.543700] R10: 0000000000000000 R11: 0000000000000206 R12: 254ddb1cc9599d7e [ 48.550968] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 48.558299] [ 48.559921] Allocated by task 3041: [ 48.563539] save_stack_trace+0x16/0x20 [ 48.567564] save_stack+0x43/0xd0 [ 48.571011] kasan_kmalloc+0xad/0xe0 [ 48.574764] __kmalloc_node+0x47/0x70 [ 48.578571] kvmalloc_node+0x64/0xd0 [ 48.582290] alloc_netdev_mqs+0x16e/0xed0 [ 48.586440] __tun_chr_ioctl+0x12be/0x3d70 [ 48.590713] tun_chr_ioctl+0x2a/0x40 [ 48.594452] do_vfs_ioctl+0x1b1/0x1530 [ 48.598368] SyS_ioctl+0x8f/0xc0 [ 48.601729] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 48.606508] [ 48.608129] Freed by task 3041: [ 48.611416] save_stack_trace+0x16/0x20 [ 48.615431] save_stack+0x43/0xd0 [ 48.618889] kasan_slab_free+0x71/0xc0 [ 48.622782] kfree+0xca/0x250 [ 48.625932] kvfree+0x36/0x60 [ 48.629042] free_netdev+0x2cf/0x360 [ 48.632904] __tun_chr_ioctl+0x2d30/0x3d70 [ 48.637209] tun_chr_ioctl+0x2a/0x40 [ 48.640954] do_vfs_ioctl+0x1b1/0x1530 [ 48.644894] SyS_ioctl+0x8f/0xc0 [ 48.648308] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 48.653133] [ 48.654763] The buggy address belongs to the object at ffff8801cc4682c0 [ 48.654763] which belongs to the cache kmalloc-16384 of size 16384 [ 48.667812] The buggy address is located 13320 bytes inside of [ 48.667812] 16384-byte region [ffff8801cc4682c0, ffff8801cc46c2c0) [ 48.680089] The buggy address belongs to the page: [ 48.685022] page:ffffea0007311a00 count:1 mapcount:0 mapping:ffff8801cc4682c0 index:0x0 compound_mapcount: 0 [ 48.694995] flags: 0x200000000008100(slab|head) [ 48.699654] raw: 0200000000008100 ffff8801cc4682c0 0000000000000000 0000000100000001 [ 48.707565] raw: ffffea00074f8a20 ffffea0007313220 ffff8801dac02200 0000000000000000 [ 48.715487] page dumped because: kasan: bad access detected [ 48.721192] [ 48.722806] Memory state around the buggy address: [ 48.727763] ffff8801cc46b580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.735119] ffff8801cc46b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.743161] >ffff8801cc46b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.750519] ^ [ 48.756282] ffff8801cc46b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.763638] ffff8801cc46b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 48.770991] ================================================================== [ 48.778346] Disabling lock debugging due to kernel taint [ 48.783789] Kernel panic - not syncing: panic_on_warn set ... [ 48.783789] [ 48.791187] CPU: 1 PID: 3041 Comm: syzkaller884634 Tainted: G B 4.13.0+ #70 [ 48.799404] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.808748] Call Trace: [ 48.811334] dump_stack+0x194/0x257 [ 48.814951] ? arch_local_irq_restore+0x53/0x53 [ 48.819695] ? vprintk_default+0x28/0x30 [ 48.823833] ? __internal_add_timer+0x1a0/0x2d0 [ 48.828501] panic+0x1e4/0x417 [ 48.831740] ? __warn+0x1d9/0x1d9 [ 48.835197] ? __internal_add_timer+0x275/0x2d0 [ 48.839895] kasan_end_report+0x50/0x50 [ 48.844428] kasan_report+0x137/0x340 [ 48.848391] __asan_report_store8_noabort+0x17/0x20 [ 48.853414] __internal_add_timer+0x275/0x2d0 [ 48.857909] ? calc_wheel_index+0x200/0x200 [ 48.862318] mod_timer+0x622/0x15b0 [ 48.865937] ? mod_timer_pending+0x14e0/0x14e0 [ 48.870654] ? __lock_is_held+0xbc/0x140 [ 48.874721] ? __lock_is_held+0xbc/0x140 [ 48.878779] ? __lockdep_init_map+0xe4/0x650 [ 48.883185] ? lockdep_init_map+0x3d/0x70 [ 48.887332] ? rcu_read_lock_sched_held+0x108/0x120 [ 48.892335] ? init_timer_key+0x126/0x3b0 [ 48.896576] ? try_to_del_timer_sync+0x120/0x120 [ 48.901321] ? round_jiffies_up+0xce/0x100 [ 48.905591] ? __round_jiffies_up_relative+0x150/0x150 [ 48.910866] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 48.915783] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 48.921348] __tun_chr_ioctl+0x1b2c/0x3d70 [ 48.925619] ? tun_select_queue+0x580/0x580 [ 48.929934] ? lock_downgrade+0x990/0x990 [ 48.934102] ? check_same_owner+0x320/0x320 [ 48.938421] ? __handle_mm_fault+0x3840/0x3840 [ 48.943619] ? vmacache_find+0x61/0x270 [ 48.947596] ? tun_chr_compat_ioctl+0x30/0x30 [ 48.952148] tun_chr_ioctl+0x2a/0x40 [ 48.955846] ? tun_chr_ioctl+0x2a/0x40 [ 48.959730] do_vfs_ioctl+0x1b1/0x1530 [ 48.963611] ? ioctl_preallocate+0x2b0/0x2b0 [ 48.968008] ? selinux_capable+0x40/0x40 [ 48.972090] ? putname+0xf3/0x130 [ 48.975572] ? do_sys_open+0x320/0x6d0 [ 48.979452] ? security_file_ioctl+0x7d/0xb0 [ 48.983892] ? security_file_ioctl+0x89/0xb0 [ 48.988291] SyS_ioctl+0x8f/0xc0 [ 48.991652] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 48.996389] RIP: 0033:0x443db9 [ 48.999559] RSP: 002b:00007fff43f5a4d8 EFLAGS: 00000206 ORIG_RAX: 0000000000000010 [ 49.007288] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443db9 [ 49.014588] RDX: 0000000020c12000 RSI: 00000000400454ca RDI: 0000000000000004 [ 49.021850] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 49.029154] R10: 0000000000000000 R11: 0000000000000206 R12: 254ddb1cc9599d7e [ 49.036441] R13: 74656e2f7665642f R14: 0000000000000000 R15: 0000000000000000 [ 49.044741] Dumping ftrace buffer: [ 49.048314] (ftrace buffer empty) [ 49.052009] Kernel Offset: disabled [ 49.055677] Rebooting in 86400 seconds..