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 syzkaller login: [ 22.966668] sshd (4412) used greatest stack depth: 16552 bytes left Warning: Permanently added '10.128.0.40' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 125.169763] ================================================================== [ 125.177271] BUG: KASAN: use-after-free in snd_pcm_timer_resolution+0xa3/0xc0 [ 125.184433] Read of size 4 at addr ffff8801c8fe8dd0 by task syzkaller061898/6686 [ 125.191938] [ 125.193544] CPU: 1 PID: 6686 Comm: syzkaller061898 Not tainted 4.16.0-rc7+ #5 [ 125.200788] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 125.210213] Call Trace: [ 125.212780] dump_stack+0x194/0x24d [ 125.216387] ? arch_local_irq_restore+0x53/0x53 [ 125.221121] ? show_regs_print_info+0x18/0x18 [ 125.225592] ? ktime_get_ts64+0x328/0x4d0 [ 125.229733] ? snd_pcm_timer_resolution+0xa3/0xc0 [ 125.234553] print_address_description+0x73/0x250 [ 125.239371] ? snd_pcm_timer_resolution+0xa3/0xc0 [ 125.244190] kasan_report+0x23c/0x360 [ 125.247974] __asan_report_load4_noabort+0x14/0x20 [ 125.252878] snd_pcm_timer_resolution+0xa3/0xc0 [ 125.257523] snd_timer_notify1+0x10f/0x400 [ 125.261737] ? snd_dma_free_pages+0x400/0x400 [ 125.266212] ? snd_timer_free_system+0x50/0x50 [ 125.270770] ? lock_release+0xa40/0xa40 [ 125.274732] snd_timer_start1+0x586/0x8f0 [ 125.278863] ? snd_timer_s_function+0x120/0x120 [ 125.283506] ? snd_timer_user_ioctl+0x51/0x7d [ 125.287976] ? sprintf+0xb8/0xf0 [ 125.291334] snd_timer_start+0x5d/0xa0 [ 125.295203] snd_timer_user_start.isra.12+0xde/0x130 [ 125.300283] __snd_timer_user_ioctl+0x1771/0x2c10 [ 125.305114] ? find_held_lock+0x35/0x1d0 [ 125.309154] ? snd_timer_user_open+0x170/0x170 [ 125.313717] ? snd_timer_user_ioctl+0x6a/0x7d [ 125.318188] ? lock_downgrade+0x980/0x980 [ 125.322315] ? unwind_get_return_address+0x61/0xa0 [ 125.327222] ? __save_stack_trace+0x7e/0xd0 [ 125.331532] ? __handle_mm_fault+0x5ba/0x38c0 [ 125.336013] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 125.340842] ? wait_for_completion+0x770/0x770 [ 125.345410] ? handle_mm_fault+0x35b/0xb10 [ 125.349626] ? find_held_lock+0x35/0x1d0 [ 125.353679] ? snd_timer_user_ioctl_compat+0x8e0/0x8e0 [ 125.358931] snd_timer_user_ioctl+0x5f/0x7d [ 125.363244] do_vfs_ioctl+0x1b1/0x1520 [ 125.367108] ? handle_mm_fault+0x465/0xb10 [ 125.371317] ? check_same_owner+0x320/0x320 [ 125.375618] ? ioctl_preallocate+0x2b0/0x2b0 [ 125.380003] ? fget_raw+0x20/0x20 [ 125.383436] ? up_read+0x1a/0x40 [ 125.386780] ? __do_page_fault+0x3d6/0xc90 [ 125.390992] ? do_sys_open+0x320/0x6d0 [ 125.394862] ? mm_fault_error+0x2c0/0x2c0 [ 125.398989] ? security_file_ioctl+0x89/0xb0 [ 125.403378] SyS_ioctl+0x8f/0xc0 [ 125.406721] ? do_vfs_ioctl+0x1520/0x1520 [ 125.410851] do_syscall_64+0x281/0x940 [ 125.414718] ? __do_page_fault+0xc90/0xc90 [ 125.418930] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 125.423663] ? syscall_return_slowpath+0x550/0x550 [ 125.428570] ? syscall_return_slowpath+0x2ac/0x550 [ 125.433477] ? prepare_exit_to_usermode+0x350/0x350 [ 125.438473] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 125.443820] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 125.448647] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 125.453811] RIP: 0033:0x445309 [ 125.456974] RSP: 002b:00007ffd6c1c5768 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ 125.464657] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445309 [ 125.471903] RDX: 0000000000445309 RSI: 00000000000054a2 RDI: 0000000000000003 [ 125.479148] RBP: 0000000000000000 R08: 000000006c1c58e8 R09: 000000006c1c58e8 [ 125.486391] R10: 000000006c1c58e8 R11: 0000000000000217 R12: 000000000001e8d9 [ 125.493635] R13: 0000000000402bd0 R14: 00000000006d1440 R15: 0000000000000000 [ 125.500902] [ 125.502505] Allocated by task 6678: [ 125.506114] save_stack+0x43/0xd0 [ 125.509539] kasan_kmalloc+0xad/0xe0 [ 125.513227] kmem_cache_alloc_trace+0x136/0x740 [ 125.517881] snd_pcm_attach_substream+0x3c5/0xb60 [ 125.522696] snd_pcm_open_substream+0x95/0x3b0 [ 125.527251] snd_pcm_oss_open+0x7cf/0x1540 [ 125.531462] soundcore_open+0x321/0x630 [ 125.535409] chrdev_open+0x257/0x730 [ 125.539096] do_dentry_open+0x667/0xd40 [ 125.543043] vfs_open+0x107/0x220 [ 125.546480] path_openat+0x1151/0x3530 [ 125.550341] do_filp_open+0x25b/0x3b0 [ 125.554116] do_sys_open+0x502/0x6d0 [ 125.557800] SyS_openat+0x30/0x40 [ 125.561230] do_syscall_64+0x281/0x940 [ 125.565092] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 125.570252] [ 125.571857] Freed by task 6678: [ 125.575109] save_stack+0x43/0xd0 [ 125.578534] __kasan_slab_free+0x11a/0x170 [ 125.582739] kasan_slab_free+0xe/0x10 [ 125.586514] kfree+0xd9/0x260 [ 125.589594] snd_pcm_detach_substream+0x134/0x290 [ 125.594411] snd_pcm_release_substream.part.44+0x23d/0x300 [ 125.600021] snd_pcm_release_substream+0x59/0x70 [ 125.604753] snd_pcm_oss_release_file.part.18+0x71/0xa0 [ 125.610089] snd_pcm_oss_release+0x104/0x280 [ 125.614471] __fput+0x327/0x7e0 [ 125.617724] ____fput+0x15/0x20 [ 125.620978] task_work_run+0x199/0x270 [ 125.624841] do_exit+0x9bb/0x1ad0 [ 125.628268] do_group_exit+0x149/0x400 [ 125.632128] SyS_exit_group+0x1d/0x20 [ 125.635912] do_syscall_64+0x281/0x940 [ 125.639774] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 125.644932] [ 125.646535] The buggy address belongs to the object at ffff8801c8fe8ac0 [ 125.646535] which belongs to the cache kmalloc-2048 of size 2048 [ 125.659338] The buggy address is located 784 bytes inside of [ 125.659338] 2048-byte region [ffff8801c8fe8ac0, ffff8801c8fe92c0) [ 125.671272] The buggy address belongs to the page: [ 125.676176] page:ffffea000723fa00 count:1 mapcount:0 mapping:ffff8801c8fe8240 index:0x0 compound_mapcount: 0 [ 125.686120] flags: 0x2fffc0000008100(slab|head) [ 125.690767] raw: 02fffc0000008100 ffff8801c8fe8240 0000000000000000 0000000100000003 [ 125.698622] raw: ffffea00070961a0 ffffea00071cb3a0 ffff8801dac00c40 0000000000000000 [ 125.706474] page dumped because: kasan: bad access detected [ 125.712156] [ 125.713761] Memory state around the buggy address: [ 125.718664] ffff8801c8fe8c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.726008] ffff8801c8fe8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.733339] >ffff8801c8fe8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.740673] ^ [ 125.746615] ffff8801c8fe8e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.753957] ffff8801c8fe8e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 125.761289] ================================================================== [ 125.768619] Disabling lock debugging due to kernel taint [ 125.774039] Kernel panic - not syncing: panic_on_warn set ... [ 125.774039] [ 125.781375] CPU: 1 PID: 6686 Comm: syzkaller061898 Tainted: G B 4.16.0-rc7+ #5 [ 125.789918] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 125.799245] Call Trace: [ 125.801808] dump_stack+0x194/0x24d [ 125.805412] ? arch_local_irq_restore+0x53/0x53 [ 125.810065] ? kasan_end_report+0x32/0x50 [ 125.814186] ? lock_downgrade+0x980/0x980 [ 125.818317] ? vsnprintf+0x1ed/0x1900 [ 125.822093] ? snd_dma_free_pages+0x3c0/0x400 [ 125.826561] panic+0x1e4/0x41c [ 125.829727] ? refcount_error_report+0x214/0x214 [ 125.834461] ? add_taint+0x40/0x50 [ 125.837972] ? add_taint+0x1c/0x50 [ 125.841486] ? snd_pcm_timer_resolution+0xa3/0xc0 [ 125.846300] kasan_end_report+0x50/0x50 [ 125.850246] kasan_report+0x149/0x360 [ 125.854023] __asan_report_load4_noabort+0x14/0x20 [ 125.858925] snd_pcm_timer_resolution+0xa3/0xc0 [ 125.863572] snd_timer_notify1+0x10f/0x400 [ 125.867780] ? snd_dma_free_pages+0x400/0x400 [ 125.872249] ? snd_timer_free_system+0x50/0x50 [ 125.876802] ? lock_release+0xa40/0xa40 [ 125.880755] snd_timer_start1+0x586/0x8f0 [ 125.884883] ? snd_timer_s_function+0x120/0x120 [ 125.889699] ? snd_timer_user_ioctl+0x51/0x7d [ 125.894166] ? sprintf+0xb8/0xf0 [ 125.897512] snd_timer_start+0x5d/0xa0 [ 125.901373] snd_timer_user_start.isra.12+0xde/0x130 [ 125.906449] __snd_timer_user_ioctl+0x1771/0x2c10 [ 125.911265] ? find_held_lock+0x35/0x1d0 [ 125.915303] ? snd_timer_user_open+0x170/0x170 [ 125.919861] ? snd_timer_user_ioctl+0x6a/0x7d [ 125.924328] ? lock_downgrade+0x980/0x980 [ 125.928449] ? unwind_get_return_address+0x61/0xa0 [ 125.933438] ? __save_stack_trace+0x7e/0xd0 [ 125.937738] ? __handle_mm_fault+0x5ba/0x38c0 [ 125.942212] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 125.947031] ? wait_for_completion+0x770/0x770 [ 125.951591] ? handle_mm_fault+0x35b/0xb10 [ 125.955803] ? find_held_lock+0x35/0x1d0 [ 125.959847] ? snd_timer_user_ioctl_compat+0x8e0/0x8e0 [ 125.965096] snd_timer_user_ioctl+0x5f/0x7d [ 125.969394] do_vfs_ioctl+0x1b1/0x1520 [ 125.973254] ? handle_mm_fault+0x465/0xb10 [ 125.977462] ? check_same_owner+0x320/0x320 [ 125.981758] ? ioctl_preallocate+0x2b0/0x2b0 [ 125.986145] ? fget_raw+0x20/0x20 [ 125.989573] ? up_read+0x1a/0x40 [ 125.992912] ? __do_page_fault+0x3d6/0xc90 [ 125.997117] ? do_sys_open+0x320/0x6d0 [ 126.000985] ? mm_fault_error+0x2c0/0x2c0 [ 126.005107] ? security_file_ioctl+0x89/0xb0 [ 126.009490] SyS_ioctl+0x8f/0xc0 [ 126.012829] ? do_vfs_ioctl+0x1520/0x1520 [ 126.016951] do_syscall_64+0x281/0x940 [ 126.020809] ? __do_page_fault+0xc90/0xc90 [ 126.025016] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 126.029745] ? syscall_return_slowpath+0x550/0x550 [ 126.034649] ? syscall_return_slowpath+0x2ac/0x550 [ 126.039550] ? prepare_exit_to_usermode+0x350/0x350 [ 126.044539] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 126.049878] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 126.054710] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 126.059874] RIP: 0033:0x445309 [ 126.063034] RSP: 002b:00007ffd6c1c5768 EFLAGS: 00000217 ORIG_RAX: 0000000000000010 [ 126.070713] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000445309 [ 126.077956] RDX: 0000000000445309 RSI: 00000000000054a2 RDI: 0000000000000003 [ 126.085196] RBP: 0000000000000000 R08: 000000006c1c58e8 R09: 000000006c1c58e8 [ 126.092438] R10: 000000006c1c58e8 R11: 0000000000000217 R12: 000000000001e8d9 [ 126.099680] R13: 0000000000402bd0 R14: 00000000006d1440 R15: 0000000000000000 [ 127.180709] Shutting down cpus with NMI [ 127.185180] Dumping ftrace buffer: [ 127.188698] (ftrace buffer empty) [ 127.192383] Kernel Offset: disabled [ 127.195996] Rebooting in 86400 seconds..