BUG: KASAN: use-after-free in disk_unblock_events+0x51/0x60 block/genhd.c:1632 Read of size 8 at addr ffff8801c60ef880 by task blkid/4601 CPU: 1 PID: 4601 Comm: blkid Not tainted 4.14.0-rc6+ #60 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:16 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:52 print_address_description+0x73/0x250 mm/kasan/report.c:252 kasan_report_error mm/kasan/report.c:351 [inline] kasan_report+0x25b/0x340 mm/kasan/report.c:409 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430 disk_unblock_events+0x51/0x60 block/genhd.c:1632 __blkdev_get+0x78d/0xf90 fs/block_dev.c:1547 blkdev_get+0x3a1/0xad0 fs/block_dev.c:1603 blkdev_open+0x1c9/0x250 fs/block_dev.c:1761 do_dentry_open+0x664/0xd40 fs/open.c:752 vfs_open+0x107/0x220 fs/open.c:866 do_last fs/namei.c:3387 [inline] path_openat+0x1151/0x3520 fs/namei.c:3527 do_filp_open+0x25b/0x3b0 fs/namei.c:3562 do_sys_open+0x502/0x6d0 fs/open.c:1059 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0xbe RIP: 0033:0x7eff1919c120 RSP: 002b:00007ffec5237e18 EFLAGS: 00000246 ORIG_RAX: 0000000000000002 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007eff1919c120 RDX: 00007ffec5239f34 RSI: 0000000000000000 RDI: 00007ffec5239f34 RBP: 0000000000000082 R08: 0000000000000078 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000feb030 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000005 Allocated by task 4184: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551 kmem_cache_alloc_node_trace+0x150/0x750 mm/slab.c:3670 kmalloc_node include/linux/slab.h:531 [inline] kzalloc_node include/linux/slab.h:677 [inline] alloc_disk_node+0xb4/0x4e0 block/genhd.c:1375 alloc_disk+0x18/0x20 block/genhd.c:1359 loop_add+0x45c/0xa50 drivers/block/loop.c:1795 loop_probe+0x16d/0x1a0 drivers/block/loop.c:1902 kobj_lookup+0x2ac/0x410 drivers/base/map.c:124 get_gendisk+0x37/0x230 block/genhd.c:773 __blkdev_get+0x3ea/0xf90 fs/block_dev.c:1445 blkdev_get+0x5ca/0xad0 fs/block_dev.c:1603 blkdev_open+0x1c9/0x250 fs/block_dev.c:1761 do_dentry_open+0x664/0xd40 fs/open.c:752 vfs_open+0x107/0x220 fs/open.c:866 do_last fs/namei.c:3387 [inline] path_openat+0x1151/0x3520 fs/namei.c:3527 do_filp_open+0x25b/0x3b0 fs/namei.c:3562 do_sys_open+0x502/0x6d0 fs/open.c:1059 C_SYSC_open fs/open.c:1096 [inline] compat_SyS_open+0x2a/0x40 fs/open.c:1094 do_syscall_32_irqs_on arch/x86/entry/common.c:329 [inline] do_fast_syscall_32+0x3f2/0xf05 arch/x86/entry/common.c:391 entry_SYSENTER_compat+0x51/0x60 arch/x86/entry/entry_64_compat.S:124 Freed by task 4601: save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59 save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track mm/kasan/kasan.c:459 [inline] kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free mm/slab.c:3503 [inline] kfree+0xca/0x250 mm/slab.c:3820 disk_release+0x327/0x410 block/genhd.c:1218 device_release+0x7c/0x200 drivers/base/core.c:814 kobject_cleanup lib/kobject.c:648 [inline] kobject_release lib/kobject.c:677 [inline] kref_put include/linux/kref.h:70 [inline] kobject_put+0x14c/0x240 lib/kobject.c:694 put_disk+0x23/0x30 block/genhd.c:1440 __blkdev_get+0x6ed/0xf90 fs/block_dev.c:1540 blkdev_get+0x3a1/0xad0 fs/block_dev.c:1603 blkdev_open+0x1c9/0x250 fs/block_dev.c:1761 do_dentry_open+0x664/0xd40 fs/open.c:752 vfs_open+0x107/0x220 fs/open.c:866 do_last fs/namei.c:3387 [inline] path_openat+0x1151/0x3520 fs/namei.c:3527 do_filp_open+0x25b/0x3b0 fs/namei.c:3562 do_sys_open+0x502/0x6d0 fs/open.c:1059 SYSC_open fs/open.c:1077 [inline] SyS_open+0x2d/0x40 fs/open.c:1072 entry_SYSCALL_64_fastpath+0x1f/0xbe The buggy address belongs to the object at ffff8801c60ef300 which belongs to the cache kmalloc-2048 of size 2048 The buggy address is located 1408 bytes inside of 2048-byte region [ffff8801c60ef300, ffff8801c60efb00) The buggy address belongs to the page: page:ffffea0007183b80 count:1 mapcount:0 mapping:ffff8801c60ee200 index:0x0 compound_mapcount: 0 flags: 0x200000000008100(slab|head) raw: 0200000000008100 ffff8801c60ee200 0000000000000000 0000000100000003 raw: ffffea00071946a0 ffffea000718eba0 ffff8801dac00c40 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8801c60ef780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c60ef800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8801c60ef880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8801c60ef900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8801c60ef980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================