Warning: Permanently added '10.128.0.27' (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 syzkaller login: [ 31.919619] ================================================================== [ 31.920853] BUG: KASAN: use-after-free in disk_unblock_events+0x55/0x60 [ 31.921972] Read of size 8 at addr ffff8801cecc9660 by task syz-executor862/2075 [ 31.923271] [ 31.923537] CPU: 1 PID: 2075 Comm: syz-executor862 Not tainted 4.9.155+ #27 [ 31.924599] ffff8801cfb3f730 ffffffff81b47871 0000000000000000 ffffea00073b3200 [ 31.925927] ffff8801cecc9660 0000000000000008 ffffffff81b19dd5 ffff8801cfb3f768 [ 31.927281] ffffffff81502825 0000000000000000 ffff8801cecc9660 ffff8801cecc9660 [ 31.928480] Call Trace: [ 31.928975] [] dump_stack+0xc1/0x120 [ 31.929806] [] ? disk_unblock_events+0x55/0x60 [ 31.930932] [] print_address_description+0x6f/0x238 [ 31.931938] [] ? disk_unblock_events+0x55/0x60 [ 31.932825] [] kasan_report.cold+0x8c/0x2ba [ 31.933689] [] __asan_report_load8_noabort+0x14/0x20 [ 31.934801] [] disk_unblock_events+0x55/0x60 [ 31.935698] [] __blkdev_get+0x6ba/0xeb0 [ 31.936460] [] ? __blkdev_put+0x840/0x840 [ 31.937321] [] ? __might_sleep+0x95/0x1a0 [ 31.938118] [] blkdev_get+0x2e8/0x920 [ 31.938870] [] ? debug_lockdep_rcu_enabled+0x71/0xa0 [ 31.939776] [] ? bd_may_claim+0xd0/0xd0 [ 31.945496] [] ? bd_acquire+0xf9/0x250 [ 31.951016] [] ? bd_acquire+0x12f/0x250 [ 31.956622] [] ? _raw_spin_unlock+0x2d/0x50 [ 31.962571] [] blkdev_open+0x1aa/0x250 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 31.968281] [] do_dentry_open+0x3ef/0xc80 [ 31.974059] [] ? blkdev_get_by_dev+0x80/0x80 [ 31.980100] [] vfs_open+0x105/0x230 [ 31.985357] [] ? may_open.isra.0+0x139/0x290 [ 31.991436] [] path_openat+0xbf5/0x2f60 [ 31.997047] [] ? path_mountpoint+0x6d0/0x6d0 [ 32.003139] [] do_filp_open+0x1a1/0x280 [ 32.008746] [] ? may_open_dev+0xe0/0xe0 [ 32.014350] [] ? __alloc_fd+0x1d4/0x490 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.019958] [] ? _raw_spin_unlock+0x2d/0x50 [ 32.026090] [] ? __alloc_fd+0x1d4/0x490 [ 32.031698] [] do_sys_open+0x2f0/0x610 [ 32.037212] [] ? filp_open+0x70/0x70 [ 32.042552] [] ? __do_page_fault+0x545/0xa60 [ 32.048596] [] SyS_open+0x2d/0x40 [ 32.053754] [] ? do_sys_open+0x610/0x610 [ 32.059454] [] do_syscall_64+0x1ad/0x570 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.065152] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.072057] [ 32.073671] Allocated by task 2075: [ 32.077284] save_stack_trace+0x16/0x20 [ 32.081235] kasan_kmalloc.part.0+0x62/0xf0 [ 32.085543] kasan_kmalloc+0xb7/0xd0 [ 32.089233] kmem_cache_alloc_trace+0x115/0x2d0 [ 32.094399] alloc_disk_node+0x50/0x3c0 [ 32.098345] alloc_disk+0x1b/0x20 [ 32.101815] loop_add+0x37e/0x7b0 [ 32.105248] loop_control_ioctl+0x132/0x2f0 [ 32.109598] do_vfs_ioctl+0xb87/0x11d0 [ 32.113476] SyS_ioctl+0x8f/0xc0 [ 32.116825] do_syscall_64+0x1ad/0x570 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.120779] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.125971] [ 32.127573] Freed by task 2075: [ 32.130828] save_stack_trace+0x16/0x20 [ 32.134822] kasan_slab_free+0xb0/0x190 [ 32.138779] kfree+0xfb/0x310 [ 32.141865] disk_release+0x255/0x330 [ 32.145660] device_release+0x7d/0x220 [ 32.149562] kobject_put+0x150/0x260 [ 32.153272] put_disk+0x23/0x30 [ 32.156549] __blkdev_get+0x61a/0xeb0 [ 32.160332] blkdev_get+0x2e8/0x920 [ 32.163942] blkdev_open+0x1aa/0x250 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.167635] do_dentry_open+0x3ef/0xc80 [ 32.171707] vfs_open+0x105/0x230 [ 32.175146] path_openat+0xbf5/0x2f60 [ 32.179180] do_filp_open+0x1a1/0x280 [ 32.182962] do_sys_open+0x2f0/0x610 [ 32.186649] SyS_open+0x2d/0x40 [ 32.189907] do_syscall_64+0x1ad/0x570 [ 32.193920] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.199033] [ 32.200643] The buggy address belongs to the object at ffff8801cecc9100 [ 32.200643] which belongs to the cache kmalloc-2048 of size 2048 [ 32.213456] The buggy address is located 1376 bytes inside of executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.213456] 2048-byte region [ffff8801cecc9100, ffff8801cecc9900) [ 32.225482] The buggy address belongs to the page: [ 32.230390] page:ffffea00073b3200 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 32.240570] flags: 0x4000000000004080(slab|head) [ 32.245297] page dumped because: kasan: bad access detected [ 32.250976] [ 32.252576] Memory state around the buggy address: [ 32.257561] ffff8801cecc9500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.264915] ffff8801cecc9580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.272248] >ffff8801cecc9600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.279578] ^ [ 32.286045] ffff8801cecc9680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.293382] ffff8801cecc9700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 32.300826] ================================================================== [ 32.308170] Disabling lock debugging due to kernel taint executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.316549] Kernel panic - not syncing: panic_on_warn set ... [ 32.316549] [ 32.323903] CPU: 1 PID: 2075 Comm: syz-executor862 Tainted: G B 4.9.155+ #27 [ 32.332289] ffff8801cfb3f670 ffffffff81b47871 ffff8801cfb3f700 ffffffff82e43a22 [ 32.340346] 00000000ffffffff 0000000000000001 ffffffff81b19dd5 ffff8801cfb3f750 [ 32.348645] ffffffff813f746a 0000000041b58ab3 ffffffff82e35b4a ffffffff813f7291 [ 32.356639] Call Trace: [ 32.359210] [] dump_stack+0xc1/0x120 [ 32.364592] [] ? disk_unblock_events+0x55/0x60 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.370846] [] panic+0x1d9/0x3bd [ 32.375885] [] ? add_taint.cold+0x16/0x16 [ 32.381870] [] ? preempt_schedule_common+0x4f/0xe0 [ 32.388469] [] ? disk_unblock_events+0x55/0x60 [ 32.394689] [] ? preempt_schedule+0x26/0x30 [ 32.400642] [] ? ___preempt_schedule+0x16/0x18 [ 32.406857] [] kasan_end_report+0x47/0x4f [ 32.412640] [] kasan_report.cold+0xa9/0x2ba executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.418595] [] __asan_report_load8_noabort+0x14/0x20 [ 32.425437] [] disk_unblock_events+0x55/0x60 [ 32.431512] [] __blkdev_get+0x6ba/0xeb0 [ 32.437129] [] ? __blkdev_put+0x840/0x840 [ 32.442969] [] ? __might_sleep+0x95/0x1a0 [ 32.448748] [] blkdev_get+0x2e8/0x920 [ 32.454317] [] ? debug_lockdep_rcu_enabled+0x71/0xa0 [ 32.461055] [] ? bd_may_claim+0xd0/0xd0 [ 32.466659] [] ? bd_acquire+0xf9/0x250 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.472172] [] ? bd_acquire+0x12f/0x250 [ 32.477773] [] ? _raw_spin_unlock+0x2d/0x50 [ 32.483722] [] blkdev_open+0x1aa/0x250 [ 32.489243] [] do_dentry_open+0x3ef/0xc80 [ 32.495062] [] ? blkdev_get_by_dev+0x80/0x80 [ 32.501105] [] vfs_open+0x105/0x230 [ 32.506363] [] ? may_open.isra.0+0x139/0x290 [ 32.512444] [] path_openat+0xbf5/0x2f60 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.518089] [] ? path_mountpoint+0x6d0/0x6d0 [ 32.524135] [] do_filp_open+0x1a1/0x280 [ 32.529865] [] ? may_open_dev+0xe0/0xe0 [ 32.535472] [] ? __alloc_fd+0x1d4/0x490 [ 32.541075] [] ? _raw_spin_unlock+0x2d/0x50 [ 32.547090] [] ? __alloc_fd+0x1d4/0x490 [ 32.552698] [] do_sys_open+0x2f0/0x610 [ 32.558216] [] ? filp_open+0x70/0x70 [ 32.563699] [] ? __do_page_fault+0x545/0xa60 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 32.569756] [] SyS_open+0x2d/0x40 [ 32.574837] [] ? do_sys_open+0x610/0x610 [ 32.580529] [] do_syscall_64+0x1ad/0x570 [ 32.586345] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 32.594915] Kernel Offset: disabled [ 32.598525] Rebooting in 86400 seconds..