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-mmots-kasan-gce-1,10.128.15.217' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 50.435876] ================================================================== [ 50.443300] BUG: KASAN: use-after-free in __internal_add_timer+0x275/0x2d0 [ 50.450281] Write of size 8 at addr ffff8801ce1fb688 by task syzkaller383350/2989 [ 50.457877] [ 50.459481] CPU: 1 PID: 2989 Comm: syzkaller383350 Not tainted 4.13.0-mm1+ #7 [ 50.466724] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.476048] Call Trace: [ 50.478611] dump_stack+0x194/0x257 [ 50.482211] ? arch_local_irq_restore+0x53/0x53 [ 50.486851] ? show_regs_print_info+0x65/0x65 [ 50.491320] ? __kernel_text_address+0xae/0xe0 [ 50.495874] ? __internal_add_timer+0x275/0x2d0 [ 50.500516] print_address_description+0x73/0x250 [ 50.505332] ? __internal_add_timer+0x275/0x2d0 [ 50.509989] kasan_report+0x24e/0x340 [ 50.513766] __asan_report_store8_noabort+0x17/0x20 [ 50.518754] __internal_add_timer+0x275/0x2d0 [ 50.523222] ? calc_wheel_index+0x200/0x200 [ 50.527530] mod_timer+0x622/0x15b0 [ 50.531145] ? mod_timer_pending+0x14e0/0x14e0 [ 50.535699] ? __lock_is_held+0xbc/0x140 [ 50.539747] ? __lock_is_held+0xbc/0x140 [ 50.543780] ? __lockdep_init_map+0xe4/0x650 [ 50.548162] ? lockdep_init_map+0x3d/0x70 [ 50.552280] ? rcu_read_lock_sched_held+0x108/0x120 [ 50.557266] ? init_timer_key+0x126/0x3b0 [ 50.561385] ? try_to_del_timer_sync+0x120/0x120 [ 50.566113] ? round_jiffies_up+0xce/0x100 [ 50.570320] ? __round_jiffies_up_relative+0x150/0x150 [ 50.575565] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 50.580465] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 50.585980] __tun_chr_ioctl+0x1b23/0x3d20 [ 50.590194] ? tun_chr_read_iter+0x1e0/0x1e0 [ 50.594583] ? lock_downgrade+0x990/0x990 [ 50.598724] ? check_same_owner+0x320/0x320 [ 50.603019] ? __handle_mm_fault+0x39c0/0x39c0 [ 50.607577] ? vmacache_find+0x61/0x270 [ 50.611526] ? tun_chr_compat_ioctl+0x30/0x30 [ 50.615991] tun_chr_ioctl+0x2a/0x40 [ 50.619674] ? tun_chr_ioctl+0x2a/0x40 [ 50.623536] do_vfs_ioctl+0x1b1/0x1530 [ 50.627401] ? ioctl_preallocate+0x2b0/0x2b0 [ 50.631784] ? selinux_capable+0x40/0x40 [ 50.635817] ? putname+0xf3/0x130 [ 50.639247] ? do_sys_open+0x320/0x6d0 [ 50.643112] ? security_file_ioctl+0x7d/0xb0 [ 50.647492] ? security_file_ioctl+0x89/0xb0 [ 50.651875] SyS_ioctl+0x8f/0xc0 [ 50.655218] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 50.659944] RIP: 0033:0x443d59 [ 50.663105] RSP: 002b:00007ffdc0f8bc58 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 50.670785] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d59 [ 50.678024] RDX: 0000000020fbcfd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 50.685263] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 50.692504] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401a40 [ 50.699744] R13: 0000000000401ad0 R14: 0000000000000000 R15: 0000000000000000 [ 50.707008] [ 50.708615] Allocated by task 2989: [ 50.712213] save_stack_trace+0x16/0x20 [ 50.716157] save_stack+0x43/0xd0 [ 50.719578] kasan_kmalloc+0xad/0xe0 [ 50.723260] __kmalloc_node+0x47/0x70 [ 50.727031] kvmalloc_node+0x64/0xd0 [ 50.730716] alloc_netdev_mqs+0x16e/0xed0 [ 50.734834] __tun_chr_ioctl+0x12be/0x3d20 [ 50.739035] tun_chr_ioctl+0x2a/0x40 [ 50.742727] do_vfs_ioctl+0x1b1/0x1530 [ 50.746582] SyS_ioctl+0x8f/0xc0 [ 50.749919] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 50.754642] [ 50.756241] Freed by task 2989: [ 50.759490] save_stack_trace+0x16/0x20 [ 50.763434] save_stack+0x43/0xd0 [ 50.766855] kasan_slab_free+0x71/0xc0 [ 50.770716] kfree+0xca/0x250 [ 50.773791] kvfree+0x36/0x60 [ 50.776867] free_netdev+0x2cf/0x360 [ 50.780552] __tun_chr_ioctl+0x2cf6/0x3d20 [ 50.784755] tun_chr_ioctl+0x2a/0x40 [ 50.788437] do_vfs_ioctl+0x1b1/0x1530 [ 50.792293] SyS_ioctl+0x8f/0xc0 [ 50.795627] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 50.800350] [ 50.801947] The buggy address belongs to the object at ffff8801ce1f8280 [ 50.801947] which belongs to the cache kmalloc-16384 of size 16384 [ 50.814919] The buggy address is located 13320 bytes inside of [ 50.814919] 16384-byte region [ffff8801ce1f8280, ffff8801ce1fc280) [ 50.827109] The buggy address belongs to the page: [ 50.832006] page:ffffea0007387e00 count:1 mapcount:0 mapping:ffff8801ce1f8280 index:0x0 compound_mapcount: 0 [ 50.841950] flags: 0x200000000008100(slab|head) [ 50.846590] raw: 0200000000008100 ffff8801ce1f8280 0000000000000000 0000000100000001 [ 50.854442] raw: ffffea0007551420 ffffea000739fc20 ffff8801dac02200 0000000000000000 [ 50.862291] page dumped because: kasan: bad access detected [ 50.867970] [ 50.869567] Memory state around the buggy address: [ 50.874467] ffff8801ce1fb580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.881793] ffff8801ce1fb600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.889123] >ffff8801ce1fb680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.896450] ^ [ 50.900047] ffff8801ce1fb700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.907375] ffff8801ce1fb780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 50.914702] ================================================================== [ 50.922027] Disabling lock debugging due to kernel taint [ 50.927449] Kernel panic - not syncing: panic_on_warn set ... [ 50.927449] [ 50.934778] CPU: 1 PID: 2989 Comm: syzkaller383350 Tainted: G B 4.13.0-mm1+ #7 [ 50.943228] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.952546] Call Trace: [ 50.955103] dump_stack+0x194/0x257 [ 50.958698] ? arch_local_irq_restore+0x53/0x53 [ 50.963332] ? vprintk_default+0x28/0x30 [ 50.967363] ? __internal_add_timer+0x200/0x2d0 [ 50.971996] panic+0x1e4/0x417 [ 50.975154] ? __warn+0x1d9/0x1d9 [ 50.978578] ? __internal_add_timer+0x275/0x2d0 [ 50.983212] kasan_end_report+0x50/0x50 [ 50.987149] kasan_report+0x137/0x340 [ 50.990916] __asan_report_store8_noabort+0x17/0x20 [ 50.995895] __internal_add_timer+0x275/0x2d0 [ 51.000356] ? calc_wheel_index+0x200/0x200 [ 51.004648] mod_timer+0x622/0x15b0 [ 51.008243] ? mod_timer_pending+0x14e0/0x14e0 [ 51.012796] ? __lock_is_held+0xbc/0x140 [ 51.016829] ? __lock_is_held+0xbc/0x140 [ 51.020856] ? __lockdep_init_map+0xe4/0x650 [ 51.025232] ? lockdep_init_map+0x3d/0x70 [ 51.029346] ? rcu_read_lock_sched_held+0x108/0x120 [ 51.034326] ? init_timer_key+0x126/0x3b0 [ 51.038440] ? try_to_del_timer_sync+0x120/0x120 [ 51.043162] ? round_jiffies_up+0xce/0x100 [ 51.047361] ? __round_jiffies_up_relative+0x150/0x150 [ 51.052600] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 51.057493] ? selinux_tun_dev_alloc_security+0x124/0x170 [ 51.063520] __tun_chr_ioctl+0x1b23/0x3d20 [ 51.067724] ? tun_chr_read_iter+0x1e0/0x1e0 [ 51.072102] ? lock_downgrade+0x990/0x990 [ 51.076230] ? check_same_owner+0x320/0x320 [ 51.080519] ? __handle_mm_fault+0x39c0/0x39c0 [ 51.085067] ? vmacache_find+0x61/0x270 [ 51.089008] ? tun_chr_compat_ioctl+0x30/0x30 [ 51.093468] tun_chr_ioctl+0x2a/0x40 [ 51.097143] ? tun_chr_ioctl+0x2a/0x40 [ 51.100997] do_vfs_ioctl+0x1b1/0x1530 [ 51.104851] ? ioctl_preallocate+0x2b0/0x2b0 [ 51.109222] ? selinux_capable+0x40/0x40 [ 51.113249] ? putname+0xf3/0x130 [ 51.116668] ? do_sys_open+0x320/0x6d0 [ 51.120524] ? security_file_ioctl+0x7d/0xb0 [ 51.124906] ? security_file_ioctl+0x89/0xb0 [ 51.129282] SyS_ioctl+0x8f/0xc0 [ 51.132631] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 51.137351] RIP: 0033:0x443d59 [ 51.140507] RSP: 002b:00007ffdc0f8bc58 EFLAGS: 00000202 ORIG_RAX: 0000000000000010 [ 51.148179] RAX: ffffffffffffffda RBX: ffffffffffffffff RCX: 0000000000443d59 [ 51.155415] RDX: 0000000020fbcfd8 RSI: 00000000400454ca RDI: 0000000000000004 [ 51.162649] RBP: 0000000000000082 R08: 0000000000000000 R09: 0000000000000000 [ 51.169883] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000401a40 [ 51.177119] R13: 0000000000401ad0 R14: 0000000000000000 R15: 0000000000000000 [ 51.184710] Dumping ftrace buffer: [ 51.188215] (ftrace buffer empty) [ 51.191892] Kernel Offset: disabled [ 51.195488] Rebooting in 86400 seconds..