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BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x1d6d/0x36c0 fs/ext4/xattr.c:1719
Read of size 18446744073709550672 at addr ffff88812d2407b0 by task syz.3.1165/4749

CPU: 0 PID: 4749 Comm: syz.3.1165 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x280/0x290 mm/kasan/generic.c:189
 memmove+0x2d/0x70 mm/kasan/shadow.c:54
 ext4_xattr_set_entry+0x1d6d/0x36c0 fs/ext4/xattr.c:1719
 ext4_xattr_block_set+0x4d6/0x2a50 fs/ext4/xattr.c:1927
 ext4_xattr_set_handle+0xbd5/0x12a0 fs/ext4/xattr.c:2412
 ext4_xattr_set+0x1ec/0x320 fs/ext4/xattr.c:2513
 ext4_xattr_trusted_set+0x3b/0x50 fs/ext4/xattr_trusted.c:37
 __vfs_setxattr+0x42a/0x480 fs/xattr.c:177
 __vfs_setxattr_noperm+0x11e/0x4e0 fs/xattr.c:208
 __vfs_setxattr_locked+0x203/0x220 fs/xattr.c:266
 vfs_setxattr+0x8d/0x1c0 fs/xattr.c:283
 setxattr+0x1a9/0x370 fs/xattr.c:548
 path_setxattr+0x110/0x210 fs/xattr.c:567
 __do_sys_lsetxattr fs/xattr.c:589 [inline]
 __se_sys_lsetxattr fs/xattr.c:585 [inline]
 __x64_sys_lsetxattr+0xc2/0xe0 fs/xattr.c:585
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f924b173ec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9249bdc038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007f924b3cafa0 RCX: 00007f924b173ec9
RDX: 0000200000000480 RSI: 00002000000000c0 RDI: 0000200000000100
RBP: 00007f924b1f6f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f924b3cb038 R14: 00007f924b3cafa0 R15: 00007ffc16199368

The buggy address belongs to the page:
page:ffffea0004b49000 refcount:2 mapcount:0 mapping:ffff88811033c6d0 index:0x1c pfn:0x12d240
aops:def_blk_aops ino:0
flags: 0x400000000000203a(referenced|dirty|lru|active|private)
raw: 400000000000203a ffffea0004cb0ec8 ffffea0004b44108 ffff88811033c6d0
raw: 000000000000001c ffff88811c224498 00000002ffffffff ffff88810d1a6000
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff88810d1a6000
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Movable, gfp_mask 0x108c48(GFP_NOFS|__GFP_NOFAIL|__GFP_HARDWALL|__GFP_MOVABLE), pid 4749, ts 226008946591, free_ts 225558291409
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370
 __alloc_pages include/linux/gfp.h:544 [inline]
 __alloc_pages_node include/linux/gfp.h:557 [inline]
 alloc_pages_node include/linux/gfp.h:571 [inline]
 alloc_pages include/linux/gfp.h:590 [inline]
 __page_cache_alloc include/linux/pagemap.h:290 [inline]
 pagecache_get_page+0x642/0x930 mm/filemap.c:1848
 find_or_create_page include/linux/pagemap.h:402 [inline]
 grow_dev_page fs/buffer.c:976 [inline]
 grow_buffers fs/buffer.c:1045 [inline]
 __getblk_slow fs/buffer.c:1072 [inline]
 __getblk_gfp+0x212/0x780 fs/buffer.c:1370
 sb_getblk include/linux/buffer_head.h:361 [inline]
 ext4_xattr_block_set+0x1c06/0x2a50 fs/ext4/xattr.c:2108
 ext4_xattr_set_handle+0xbd5/0x12a0 fs/ext4/xattr.c:2412
 ext4_xattr_set+0x1ec/0x320 fs/ext4/xattr.c:2513
 ext4_xattr_user_set+0xc9/0xf0 fs/ext4/xattr_user.c:40
 __vfs_setxattr+0x42a/0x480 fs/xattr.c:177
 __vfs_setxattr_noperm+0x11e/0x4e0 fs/xattr.c:208
 __vfs_setxattr_locked+0x203/0x220 fs/xattr.c:266
 vfs_setxattr+0x8d/0x1c0 fs/xattr.c:283
 setxattr+0x1a9/0x370 fs/xattr.c:548
 path_setxattr+0x110/0x210 fs/xattr.c:567
 __do_sys_setxattr fs/xattr.c:582 [inline]
 __se_sys_setxattr fs/xattr.c:578 [inline]
 __x64_sys_setxattr+0xc5/0xe0 fs/xattr.c:578
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2b7/0x2d0 mm/page_alloc.c:3336
 free_unref_page_list+0x12e/0x9b0 mm/page_alloc.c:3443
 release_pages+0xe38/0xe80 mm/swap.c:1103
 __pagevec_release+0x71/0xe0 mm/swap.c:1123
 pagevec_release include/linux/pagevec.h:88 [inline]
 shmem_undo_range+0x6e1/0x1760 mm/shmem.c:969
 shmem_truncate_range mm/shmem.c:1073 [inline]
 shmem_evict_inode+0x1fd/0x9c0 mm/shmem.c:1173
 evict+0x478/0x910 fs/inode.c:612
 iput_final fs/inode.c:1736 [inline]
 iput+0x638/0x7c0 fs/inode.c:1762
 dentry_unlink_inode+0x2cf/0x380 fs/dcache.c:378
 __dentry_kill+0x44f/0x650 fs/dcache.c:583
 dentry_kill+0xc0/0x2a0 fs/dcache.c:-1
 dput+0x42/0x80 fs/dcache.c:883
 __fput+0x4fe/0x770 fs/file_table.c:294
 ____fput+0x15/0x20 fs/file_table.c:314
 task_work_run+0x127/0x190 kernel/task_work.c:189
 exit_task_work include/linux/task_work.h:33 [inline]
 do_exit+0xa4f/0x2480 kernel/exit.c:872

Memory state around the buggy address:
 ffff88812d240680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88812d240700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88812d240780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                     ^
 ffff88812d240800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88812d240880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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