==================================================================
BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x9c1/0x1e20 fs/ext4/xattr.c:1751
Read of size 18446744073709551600 at addr ffff88804cd352e8 by task syz.0.0/5362

CPU: 0 UID: 0 PID: 5362 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x2b0/0x2c0 mm/kasan/generic.c:189
 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94
 ext4_xattr_set_entry+0x9c1/0x1e20 fs/ext4/xattr.c:1751
 ext4_xattr_ibody_set+0x254/0x6a0 fs/ext4/xattr.c:2263
 ext4_destroy_inline_data_nolock+0x214/0x5b0 fs/ext4/inline.c:463
 ext4_convert_inline_data_nolock+0x1f1/0x970 fs/ext4/inline.c:1105
 ext4_convert_inline_data+0x4b3/0x5e0 fs/ext4/inline.c:1976
 ext4_page_mkwrite+0x22c/0x1190 fs/ext4/inode.c:6708
 do_page_mkwrite+0x14a/0x310 mm/memory.c:3361
 do_shared_fault mm/memory.c:5649 [inline]
 do_fault mm/memory.c:5711 [inline]
 do_pte_missing mm/memory.c:4234 [inline]
 handle_pte_fault mm/memory.c:6052 [inline]
 __handle_mm_fault+0x1916/0x5440 mm/memory.c:6195
 handle_mm_fault+0x40a/0x8e0 mm/memory.c:6364
 do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
 handle_page_fault arch/x86/mm/fault.c:1476 [inline]
 exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7fb6e3a55321
Code: 48 8b 54 24 08 48 85 d2 74 17 8b 44 24 18 0f c8 89 c0 48 89 44 24 18 48 83 fa 01 0f 85 b3 01 00 00 48 8b 44 24 10 8b 54 24 18 <89> 10 e9 15 fd ff ff 48 8b 44 24 10 8b 10 48 8b 44 24 08 48 85 c0
RSP: 002b:00007ffd2ac07eb0 EFLAGS: 00010246
RAX: 0000200000001480 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000014 RSI: 0000000000000000 RDI: 000055557f33d3c8
RBP: 00007ffd2ac07fb8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 00007fb6e3de5fac
R13: 00007fb6e3de5fa0 R14: fffffffffffffffe R15: 00007ffd2ac08000
 </TASK>

The buggy address belongs to the physical page:
page: refcount:3 mapcount:0 mapping:ffff8880008ccd80 index:0x2 pfn:0x4cd35
memcg:ffff888030ad0d00
aops:def_blk_aops ino:700000 dentry name(?):""
flags: 0x4fff18000004314(referenced|dirty|active|workingset|private|node=1|zone=1|lastcpupid=0x7ff)
raw: 04fff18000004314 0000000000000000 dead000000000122 ffff8880008ccd80
raw: 0000000000000002 ffff888032102828 00000003ffffffff ffff888030ad0d00
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_MOVABLE|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL), pid 5362, tgid 5362 (syz.0.0), ts 85199580542, free_ts 85160163113
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x21e4/0x22c0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5148
 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2416
 alloc_frozen_pages_noprof mm/mempolicy.c:2487 [inline]
 alloc_pages_noprof+0xa9/0x190 mm/mempolicy.c:2507
 folio_alloc_noprof+0x1e/0x30 mm/mempolicy.c:2517
 filemap_alloc_folio_noprof+0xdf/0x470 mm/filemap.c:1007
 __filemap_get_folio+0x3f2/0xaf0 mm/filemap.c:1981
 grow_dev_folio fs/buffer.c:1050 [inline]
 grow_buffers fs/buffer.c:1116 [inline]
 __getblk_slow fs/buffer.c:1134 [inline]
 bdev_getblk+0x1ad/0x660 fs/buffer.c:1461
 __getblk include/linux/buffer_head.h:380 [inline]
 sb_getblk include/linux/buffer_head.h:386 [inline]
 __ext4_get_inode_loc+0x561/0x1040 fs/ext4/inode.c:4866
 ext4_get_inode_loc fs/ext4/inode.c:4994 [inline]
 ext4_reserve_inode_write+0x18b/0x360 fs/ext4/inode.c:6323
 __ext4_mark_inode_dirty+0x15b/0x700 fs/ext4/inode.c:6501
 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6538
 __mark_inode_dirty+0x2ec/0xe10 fs/fs-writeback.c:2527
 generic_update_time fs/inode.c:2063 [inline]
 inode_update_time fs/inode.c:2076 [inline]
 __file_update_time fs/inode.c:2304 [inline]
 file_update_time+0x40c/0x490 fs/inode.c:2334
 ext4_page_mkwrite+0x20e/0x1190 fs/ext4/inode.c:6704
page last free pid 5363 tgid 5362 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 free_unref_folios+0xdbd/0x1520 mm/page_alloc.c:2952
 folios_put_refs+0x559/0x640 mm/swap.c:999
 free_pages_and_swap_cache+0x4be/0x520 mm/swap_state.c:267
 __tlb_batch_free_encoded_pages mm/mmu_gather.c:136 [inline]
 tlb_batch_pages_flush mm/mmu_gather.c:149 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:397 [inline]
 tlb_flush_mmu+0x3a0/0x680 mm/mmu_gather.c:404
 tlb_finish_mmu+0xc3/0x1d0 mm/mmu_gather.c:497
 vms_clear_ptes+0x42c/0x540 mm/vma.c:1235
 vms_clean_up_area mm/vma.c:1247 [inline]
 __mmap_prepare mm/vma.c:2396 [inline]
 __mmap_region mm/vma.c:2651 [inline]
 mmap_region+0x972/0x20c0 mm/vma.c:2739
 do_mmap+0xc45/0x10d0 mm/mmap.c:558
 vm_mmap_pgoff+0x2a6/0x4d0 mm/util.c:580
 ksys_mmap_pgoff+0x51f/0x760 mm/mmap.c:604
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88804cd35180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804cd35200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88804cd35280: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                          ^
 ffff88804cd35300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88804cd35380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================