[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 11.311535] random: crng init done [?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.166' (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 syzkaller login: [ 44.587363] ================================================================== [ 44.588961] BUG: KASAN: use-after-free in disk_unblock_events+0x51/0x60 [ 44.589931] Read of size 8 at addr ffff8801d9ca8de0 by task blkid/3579 [ 44.591003] [ 44.591245] CPU: 1 PID: 3579 Comm: blkid Not tainted 4.9.141+ #23 [ 44.592240] ffff8801d9d0f6f8 ffffffff81b42e79 ffffea0007672a00 ffff8801d9ca8de0 [ 44.593605] 0000000000000000 ffff8801d9ca8de0 0000000000000000 ffff8801d9d0f730 [ 44.594963] ffffffff815009b8 ffff8801d9ca8de0 0000000000000008 0000000000000000 [ 44.596227] Call Trace: [ 44.596612] [] dump_stack+0xc1/0x128 [ 44.597464] [] print_address_description+0x6c/0x234 [ 44.598445] [] kasan_report.cold.6+0x242/0x2fe [ 44.599312] [] ? disk_unblock_events+0x51/0x60 [ 44.600200] [] __asan_report_load8_noabort+0x14/0x20 [ 44.601219] [] disk_unblock_events+0x51/0x60 [ 44.602179] [] __blkdev_get+0x6b6/0xd60 [ 44.603067] [] ? __blkdev_put+0x840/0x840 [ 44.603909] [] ? fsnotify+0x114/0x1100 [ 44.604670] [] blkdev_get+0x2da/0x920 [ 44.605484] [] ? debug_lockdep_rcu_enabled+0x77/0x90 [ 44.606450] [] ? bd_may_claim+0xd0/0xd0 [ 44.607283] [] ? bd_acquire+0x27/0x250 [ 44.609225] [] ? bd_acquire+0x88/0x250 [ 44.614838] [] ? _raw_spin_unlock+0x2c/0x50 [ 44.620811] [] blkdev_open+0x1a5/0x250 [ 44.626332] [] do_dentry_open+0x3ef/0xc90 [ 44.632108] [] ? blkdev_get_by_dev+0x70/0x70 [ 44.638236] [] vfs_open+0x11c/0x210 [ 44.643565] [] ? may_open.isra.20+0x14f/0x2a0 [ 44.649695] [] path_openat+0x542/0x2790 [ 44.655304] [] ? path_mountpoint+0x6c0/0x6c0 [ 44.661343] [] ? trace_hardirqs_on+0x10/0x10 [ 44.667380] [] ? expand_files.part.3+0x3a9/0x6d0 [ 44.673762] [] do_filp_open+0x197/0x270 [ 44.679380] [] ? may_open_dev+0xe0/0xe0 executing program executing program executing program executing program executing program executing program [ 44.684993] [] ? _raw_spin_unlock+0x2c/0x50 [ 44.690944] [] ? __alloc_fd+0x1d7/0x4a0 [ 44.696552] [] do_sys_open+0x30d/0x5c0 [ 44.702080] [] ? filp_open+0x70/0x70 [ 44.707425] [] ? up_read+0x1a/0x40 [ 44.712592] [] SyS_open+0x2d/0x40 [ 44.717672] [] ? do_sys_open+0x5c0/0x5c0 [ 44.723369] [] do_syscall_64+0x19f/0x550 [ 44.729077] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 44.735996] executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.737619] Allocated by task 3576: [ 44.741247] save_stack_trace+0x16/0x20 [ 44.745219] kasan_kmalloc.part.1+0x62/0xf0 [ 44.749535] kasan_kmalloc+0xaf/0xc0 [ 44.753245] kmem_cache_alloc_trace+0x117/0x2e0 [ 44.757911] alloc_disk_node+0x54/0x3a0 [ 44.761891] alloc_disk+0x18/0x20 [ 44.765342] loop_add+0x368/0x7a0 [ 44.768790] loop_probe+0x14f/0x180 [ 44.772415] kobj_lookup+0x223/0x410 [ 44.776126] get_gendisk+0x39/0x2d0 [ 44.779744] __blkdev_get+0x351/0xd60 [ 44.783535] blkdev_get+0x488/0x920 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.787155] blkdev_open+0x1a5/0x250 [ 44.790859] do_dentry_open+0x3ef/0xc90 [ 44.794840] vfs_open+0x11c/0x210 [ 44.798297] path_openat+0x542/0x2790 [ 44.802091] do_filp_open+0x197/0x270 [ 44.805897] do_sys_open+0x30d/0x5c0 [ 44.809613] compat_SyS_open+0x2a/0x40 [ 44.813496] do_fast_syscall_32+0x2f1/0xa10 [ 44.817813] entry_SYSENTER_compat+0x90/0xa2 [ 44.822205] [ 44.823820] Freed by task 3579: [ 44.827096] save_stack_trace+0x16/0x20 [ 44.831087] kasan_slab_free+0xac/0x190 [ 44.835060] kfree+0xfb/0x310 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.838163] disk_release+0x259/0x330 [ 44.841956] device_release+0x7e/0x220 [ 44.845839] kobject_put+0x148/0x250 [ 44.849555] put_disk+0x23/0x30 [ 44.852829] __blkdev_get+0x616/0xd60 [ 44.856635] blkdev_get+0x2da/0x920 [ 44.860254] blkdev_open+0x1a5/0x250 [ 44.863959] do_dentry_open+0x3ef/0xc90 [ 44.867926] vfs_open+0x11c/0x210 [ 44.871373] path_openat+0x542/0x2790 [ 44.875167] do_filp_open+0x197/0x270 [ 44.878963] do_sys_open+0x30d/0x5c0 [ 44.882672] SyS_open+0x2d/0x40 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.885944] do_syscall_64+0x19f/0x550 [ 44.889822] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 44.894908] [ 44.896529] The buggy address belongs to the object at ffff8801d9ca8880 [ 44.896529] which belongs to the cache kmalloc-2048 of size 2048 [ 44.909357] The buggy address is located 1376 bytes inside of [ 44.909357] 2048-byte region [ffff8801d9ca8880, ffff8801d9ca9080) [ 44.921395] The buggy address belongs to the page: [ 44.926321] page:ffffea0007672a00 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.936549] flags: 0x4000000000004080(slab|head) [ 44.941291] page dumped because: kasan: bad access detected [ 44.946985] [ 44.948598] Memory state around the buggy address: [ 44.953523] ffff8801d9ca8c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.960878] ffff8801d9ca8d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.968227] >ffff8801d9ca8d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.975572] ^ executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 44.982059] ffff8801d9ca8e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.989504] ffff8801d9ca8e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 44.996875] ================================================================== [ 45.004223] Disabling lock debugging due to kernel taint [ 45.012272] Kernel panic - not syncing: panic_on_warn set ... [ 45.012272] [ 45.019742] CPU: 1 PID: 3579 Comm: blkid Tainted: G B 4.9.141+ #23 [ 45.027176] ffff8801d9d0f658 ffffffff81b42e79 ffffffff82e37630 00000000ffffffff executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.035249] 0000000000000000 0000000000000001 0000000000000000 ffff8801d9d0f718 [ 45.043322] ffffffff813f7125 0000000041b58ab3 ffffffff82e2b62b ffffffff813f6f66 [ 45.051395] Call Trace: [ 45.053981] [] dump_stack+0xc1/0x128 [ 45.059605] [] panic+0x1bf/0x39f [ 45.065141] [] ? add_taint.cold.5+0x16/0x16 [ 45.071114] [] ? ___preempt_schedule+0x16/0x18 [ 45.077347] [] kasan_end_report+0x47/0x4f [ 45.083151] [] kasan_report.cold.6+0x76/0x2fe executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.089297] [] ? disk_unblock_events+0x51/0x60 [ 45.095523] [] __asan_report_load8_noabort+0x14/0x20 [ 45.102275] [] disk_unblock_events+0x51/0x60 [ 45.108335] [] __blkdev_get+0x6b6/0xd60 [ 45.113972] [] ? __blkdev_put+0x840/0x840 [ 45.119768] [] ? fsnotify+0x114/0x1100 [ 45.125306] [] blkdev_get+0x2da/0x920 [ 45.130783] [] ? debug_lockdep_rcu_enabled+0x77/0x90 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.137535] [] ? bd_may_claim+0xd0/0xd0 [ 45.143157] [] ? bd_acquire+0x27/0x250 [ 45.148697] [] ? bd_acquire+0x88/0x250 [ 45.154231] [] ? _raw_spin_unlock+0x2c/0x50 [ 45.160203] [] blkdev_open+0x1a5/0x250 [ 45.165739] [] do_dentry_open+0x3ef/0xc90 [ 45.171532] [] ? blkdev_get_by_dev+0x70/0x70 [ 45.177585] [] vfs_open+0x11c/0x210 [ 45.182870] [] ? may_open.isra.20+0x14f/0x2a0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.189009] [] path_openat+0x542/0x2790 [ 45.194630] [] ? path_mountpoint+0x6c0/0x6c0 [ 45.200683] [] ? trace_hardirqs_on+0x10/0x10 [ 45.207001] [] ? expand_files.part.3+0x3a9/0x6d0 [ 45.213408] [] do_filp_open+0x197/0x270 [ 45.219031] [] ? may_open_dev+0xe0/0xe0 [ 45.224653] [] ? _raw_spin_unlock+0x2c/0x50 [ 45.230625] [] ? __alloc_fd+0x1d7/0x4a0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.236713] [] do_sys_open+0x30d/0x5c0 [ 45.242244] [] ? filp_open+0x70/0x70 [ 45.247604] [] ? up_read+0x1a/0x40 [ 45.252791] [] SyS_open+0x2d/0x40 [ 45.257889] [] ? do_sys_open+0x5c0/0x5c0 [ 45.263593] [] do_syscall_64+0x19f/0x550 [ 45.269300] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 45.276719] Kernel Offset: disabled [ 45.280362] Rebooting in 86400 seconds..