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BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x92b/0x1ed0 fs/ext4/xattr.c:1763
Read of size 18446744073709551600 at addr ffff888042e516b8 by task syz.4.110/6449

CPU: 0 UID: 0 PID: 6449 Comm: syz.4.110 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94
 ext4_xattr_set_entry+0x92b/0x1ed0 fs/ext4/xattr.c:1763
 ext4_xattr_ibody_set+0x262/0x710 fs/ext4/xattr.c:2275
 ext4_destroy_inline_data_nolock+0x23a/0x5f0 fs/ext4/inline.c:472
 ext4_convert_inline_data_nolock+0x208/0x980 fs/ext4/inline.c:1123
 ext4_convert_inline_data+0x484/0x5c0 fs/ext4/inline.c:1994
 ext4_setattr+0xef1/0x1d70 fs/ext4/inode.c:6032
 notify_change+0xbb8/0xec0 fs/attr.c:556
 do_truncate+0x1c2/0x250 fs/open.c:68
 vfs_truncate+0x4b7/0x540 fs/open.c:118
 ksys_truncate+0xf3/0x1c0 fs/open.c:142
 __do_sys_truncate fs/open.c:154 [inline]
 __se_sys_truncate fs/open.c:152 [inline]
 __x64_sys_truncate+0x5b/0x70 fs/open.c:152
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f366f5dde59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f366d815028 EFLAGS: 00000246 ORIG_RAX: 000000000000004c
RAX: ffffffffffffffda RBX: 00007f366f866090 RCX: 00007f366f5dde59
RDX: 0000000000000000 RSI: 0000000002fffffd RDI: 0000200000000940
RBP: 00007f366f673e6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f366f866128 R14: 00007f366f866090 R15: 00007fffff59d8d8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:5 mapcount:0 mapping:ffff888023049760 index:0xc pfn:0x42e51
memcg:ffff8880282f6d80
aops:def_blk_aops ino:700004 dentry name(?):""
flags: 0x80000000004124(referenced|lru|active|private|node=0|zone=1)
raw: 0080000000004124 ffffea0001592948 ffff88806143db78 ffff888023049760
raw: 000000000000000c ffff88803fea5c60 00000005ffffffff ffff8880282f6d80
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 6449, tgid 6416 (syz.4.110), ts 176757352048, free_ts 176755701748
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0x262a/0x26a0 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5304
 alloc_pages_mpol+0xce/0x280 mm/mempolicy.c:2490
 alloc_frozen_pages_noprof mm/mempolicy.c:2561 [inline]
 alloc_pages_noprof+0xd2/0x2f0 mm/mempolicy.c:2581
 folio_alloc_noprof+0x22/0xc0 mm/mempolicy.c:2591
 filemap_alloc_folio_noprof+0x111/0x4d0 mm/filemap.c:1013
 __filemap_get_folio_mpol+0x33f/0xf50 mm/filemap.c:2012
 __filemap_get_folio include/linux/pagemap.h:761 [inline]
 grow_dev_folio fs/buffer.c:960 [inline]
 grow_buffers fs/buffer.c:1026 [inline]
 __getblk_slow fs/buffer.c:1044 [inline]
 bdev_getblk+0x1f4/0x6e0 fs/buffer.c:1439
 __getblk include/linux/buffer_head.h:382 [inline]
 sb_getblk include/linux/buffer_head.h:388 [inline]
 __ext4_get_inode_loc+0x56c/0xf40 fs/ext4/inode.c:4891
 ext4_get_inode_loc+0x81/0xf0 fs/ext4/inode.c:5019
 ext4_convert_inline_data+0x261/0x5c0 fs/ext4/inline.c:1982
 ext4_setattr+0xef1/0x1d70 fs/ext4/inode.c:6032
 notify_change+0xbb8/0xec0 fs/attr.c:556
 do_truncate+0x1c2/0x250 fs/open.c:68
 vfs_truncate+0x4b7/0x540 fs/open.c:118
page last free pid 5602 tgid 5602 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 free_unref_folios+0xcd4/0x1910 mm/page_alloc.c:3011
 folios_put_refs+0x815/0x920 mm/swap.c:1057
 folio_batch_release include/linux/folio_batch.h:101 [inline]
 shmem_undo_range+0x4e6/0x15d0 mm/shmem.c:1149
 shmem_truncate_range mm/shmem.c:1277 [inline]
 shmem_evict_inode+0x280/0xa80 mm/shmem.c:1407
 evict+0x624/0xb50 fs/inode.c:825
 dentry_kill+0x1b9/0x880 fs/dcache.c:826
 finish_dput+0x1a/0x260 fs/dcache.c:1001
 __fput+0x699/0xa80 fs/file_table.c:520
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 __exit_to_user_mode_loop kernel/entry/common.c:70 [inline]
 exit_to_user_mode_loop+0x1fa/0x730 kernel/entry/common.c:101
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888042e51580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888042e51600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888042e51680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                        ^
 ffff888042e51700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888042e51780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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