EXT4-fs (sda1): changing journal_checksum during remount not supported; ignoring
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EXT4-fs (sda1): re-mounted. Opts: sb=0x0000000000000000,journal_async_commit,grpjquota=,noblock_validity,commit=0x0000000000000003,,errors=continue
BUG: KASAN: use-after-free in ext4_data_block_valid+0x276/0x2d0 fs/ext4/block_validity.c:211
Read of size 8 at addr ffff8801d6387bb0 by task blkid/8079

CPU: 1 PID: 8079 Comm: blkid Not tainted 4.14.78+ #28
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0xb9/0x11b lib/dump_stack.c:53
 print_address_description+0x60/0x22b mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report.cold.6+0x11b/0x2dd mm/kasan/report.c:409
 ext4_data_block_valid+0x276/0x2d0 fs/ext4/block_validity.c:211
 __check_block_validity.constprop.27+0xbc/0x200 fs/ext4/inode.c:402
 ext4_map_blocks+0xc22/0x1560 fs/ext4/inode.c:592
 ext4_getblk+0x31c/0x400 fs/ext4/inode.c:966
 ext4_bread_batch+0x78/0x330 fs/ext4/inode.c:1036
 ext4_find_entry+0x44c/0xcd0 fs/ext4/namei.c:1424
 ext4_lookup+0x133/0x590 fs/ext4/namei.c:1556
 lookup_slow+0x22b/0x440 fs/namei.c:1669
 walk_component+0x6f0/0xc10 fs/namei.c:1798
 lookup_last fs/namei.c:2266 [inline]
 path_lookupat.isra.10+0x1bc/0x890 fs/namei.c:2316
 filename_lookup.part.18+0x177/0x370 fs/namei.c:2350
 filename_lookup fs/namei.c:2343 [inline]
 user_path_at_empty+0x4b/0x80 fs/namei.c:2611
 user_path_at include/linux/namei.h:57 [inline]
 SYSC_faccessat fs/open.c:394 [inline]
 SyS_faccessat+0x20d/0x660 fs/open.c:362
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7ffb81646267
RSP: 002b:00007ffd6a054b58 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007ffb818511c8 RCX: 00007ffb81646267
RDX: 00007ffb81630158 RSI: 0000000000000004 RDI: 00007ffb8164ce30
RBP: 00007ffd6a054cb0 R08: 00007ffb81851770 R09: 0000000000000050
R10: ffffffffffffffb0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd6a07a2f4 R14: 00007ffb81851bc8 R15: 0000000000000000

Allocated by task 1:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc.part.1+0x4f/0xd0 mm/kasan/kasan.c:551
 slab_post_alloc_hook mm/slab.h:442 [inline]
 slab_alloc_node mm/slub.c:2723 [inline]
 slab_alloc mm/slub.c:2731 [inline]
 kmem_cache_alloc+0xe4/0x2b0 mm/slub.c:2736
 add_system_zone+0x261/0x4d0 fs/ext4/block_validity.c:85
 ext4_setup_system_zone+0x2e2/0x470 fs/ext4/block_validity.c:169
 ext4_fill_super+0x706c/0xb5f0 fs/ext4/super.c:4291
 mount_bdev+0x2ab/0x370 fs/super.c:1149
 mount_fs+0x28f/0x31a fs/super.c:1255
 vfs_kern_mount.part.9+0xce/0x4a0 fs/namespace.c:1056
 vfs_kern_mount fs/namespace.c:1038 [inline]
 do_new_mount fs/namespace.c:2561 [inline]
 do_mount+0x404/0x26e0 fs/namespace.c:2891
 SYSC_mount fs/namespace.c:3107 [inline]
 SyS_mount+0xe5/0x100 fs/namespace.c:3084
 do_mount_root init/do_mounts.c:366 [inline]
 mount_block_root+0x378/0x727 init/do_mounts.c:395
 prepare_namespace+0x1cf/0x20a init/do_mounts.c:600
 kernel_init_freeable+0x382/0x39f init/main.c:1091
 kernel_init+0xc/0x157 init/main.c:1000
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:402

Freed by task 8074:
 save_stack mm/kasan/kasan.c:447 [inline]
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0xac/0x190 mm/kasan/kasan.c:524
 slab_free_hook mm/slub.c:1389 [inline]
 slab_free_freelist_hook mm/slub.c:1410 [inline]
 slab_free mm/slub.c:2966 [inline]
 kmem_cache_free+0x12d/0x350 mm/slub.c:2988
 ext4_release_system_zone+0x79/0x110 fs/ext4/block_validity.c:187
 ext4_setup_system_zone+0x3a4/0x470 fs/ext4/block_validity.c:151
 ext4_remount+0xdc2/0x1c60 fs/ext4/super.c:5237
 do_remount_sb2+0x2eb/0x5f0 fs/super.c:878
 do_remount fs/namespace.c:2376 [inline]
 do_mount+0xfae/0x26e0 fs/namespace.c:2882
 SYSC_mount fs/namespace.c:3107 [inline]
 SyS_mount+0xe5/0x100 fs/namespace.c:3084
 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289
 entry_SYSCALL_64_after_hwframe+0x42/0xb7

The buggy address belongs to the object at ffff8801d6387b98
 which belongs to the cache ext4_system_zone of size 40
The buggy address is located 24 bytes inside of
 40-byte region [ffff8801d6387b98, ffff8801d6387bc0)
The buggy address belongs to the page:
page:ffffea000758e1c0 count:1 mapcount:0 mapping:          (null) index:0xffff8801d6387b60
flags: 0x4000000000000100(slab)
raw: 4000000000000100 0000000000000000 ffff8801d6387b60 0000000180490019
raw: dead000000000100 dead000000000200 ffff8801d9eb9600 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801d6387a80: fb fb fb fb fb fc fc fb fb fb fb fb fc fc fb fb
 ffff8801d6387b00: fb fb fb fc fc fb fb fb fb fb fc fc fb fb fb fb
>ffff8801d6387b80: fb fc fc fb fb fb fb fb fc fc fc fc fc fc fc fc
                                     ^
 ffff8801d6387c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801d6387c80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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