==================================================================
BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x860/0x15a0 fs/ext4/xattr.c:1708
Read of size 18446744073709551600 at addr ffff0000e1bf4eb8 by task kworker/u4:11/5481

CPU: 0 PID: 5481 Comm: kworker/u4:11 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: writeback wb_workfn (flush-7:7)
Call trace:
 dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0xfc mm/kasan/report.c:524
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x258/0x290 mm/kasan/generic.c:189
 memmove+0x48/0x90 mm/kasan/shadow.c:54
 ext4_xattr_set_entry+0x860/0x15a0 fs/ext4/xattr.c:1708
 ext4_xattr_ibody_set+0x204/0x5f8 fs/ext4/xattr.c:2215
 ext4_destroy_inline_data_nolock+0x1d8/0x4b4 fs/ext4/inline.c:468
 ext4_destroy_inline_data+0x7c/0x114 fs/ext4/inline.c:1923
 ext4_writepages+0x430/0x28b4 fs/ext4/inode.c:2763
 do_writepages+0x2b0/0x504 mm/page-writeback.c:2491
 __writeback_single_inode+0x164/0x1554 fs/fs-writeback.c:1622
 writeback_sb_inodes+0x858/0x143c fs/fs-writeback.c:1913
 wb_writeback+0x414/0xfcc fs/fs-writeback.c:2087
 wb_do_writeback fs/fs-writeback.c:2230 [inline]
 wb_workfn+0x360/0xe18 fs/fs-writeback.c:2270
 process_one_work+0x7f8/0x13a4 kernel/workqueue.c:2292
 worker_thread+0x8c4/0xfec kernel/workqueue.c:2439
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

The buggy address belongs to the physical page:
page:0000000037920782 refcount:2 mapcount:0 mapping:00000000ae5c8e4c index:0x2 pfn:0x121bf4
memcg:ffff0000d07c4000
aops:def_blk_aops ino:700007
flags: 0x5ffd6000002205e(referenced|uptodate|dirty|lru|workingset|private|mappedtodisk|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffd6000002205e fffffc0003ef12c8 fffffc0003f24e48 ffff0000c57e9310
raw: 0000000000000002 ffff0000e20b7570 00000002ffffffff ffff0000d07c4000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000e1bf4d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000e1bf4e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff0000e1bf4e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                        ^
 ffff0000e1bf4f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff0000e1bf4f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================
EXT4-fs error (device loop7): ext4_validate_block_bitmap:438: comm kworker/u4:11: bg 0: block 32: padding at end of block bitmap is not set
EXT4-fs (loop7): Delayed block allocation failed for inode 15 at logical offset 4 with max blocks 2048 with error 28
EXT4-fs (loop7): This should not happen!! Data will be lost

EXT4-fs (loop7): Total free blocks count 0
EXT4-fs (loop7): Free/Dirty block details
EXT4-fs (loop7): free_blocks=0
EXT4-fs (loop7): dirty_blocks=2944
EXT4-fs (loop7): Block reservation details