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BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x1d79/0x3860 fs/ext4/xattr.c:1708
Read of size 18446744073709550624 at addr ffff888130b697e0 by task syz.3.851/3750

CPU: 1 PID: 3750 Comm: syz.3.851 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x1a7/0x208 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+0x249/0x2a0 mm/kasan/generic.c:189
 memmove+0x2d/0x70 mm/kasan/shadow.c:54
 ext4_xattr_set_entry+0x1d79/0x3860 fs/ext4/xattr.c:1708
 ext4_xattr_block_set+0x4e0/0x2a80 fs/ext4/xattr.c:1916
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2398
 ext4_xattr_set+0x1f4/0x310 fs/ext4/xattr.c:2499
 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+0x1df/0x3f0 fs/xattr.c:548
 path_setxattr+0x11f/0x230 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: 0033:0x7f44da9e6629
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:00007f44d9420028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007f44dac60090 RCX: 00007f44da9e6629
RDX: 0000200000000280 RSI: 00002000000000c0 RDI: 0000200000000000
RBP: 00007f44daa7cb39 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f44dac60128 R14: 00007f44dac60090 R15: 00007ffc9952b468

The buggy address belongs to the page:
page:ffffea0004c2da40 refcount:2 mapcount:0 mapping:ffff888110b64f50 index:0x1c pfn:0x130b69
aops:def_blk_aops ino:0
flags: 0x400000000000203a(referenced|dirty|lru|active|private)
raw: 400000000000203a ffffea0004a48a08 ffffea00045217c8 ffff888110b64f50
raw: 000000000000001c ffff8881401d4348 00000002ffffffff ffff88810dfc4000
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff88810dfc4000
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 3749, ts 157546994267, free_ts 157544582715
 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+0x223b/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x290/0x620 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+0x63e/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+0x1ccc/0x2a80 fs/ext4/xattr.c:2097
 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2398
 ext4_xattr_set+0x1f4/0x310 fs/ext4/xattr.c:2499
 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+0x1df/0x3f0 fs/xattr.c:548
 path_setxattr+0x11f/0x230 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+0x129/0x9c0 mm/page_alloc.c:3443
 release_pages+0xe52/0xea0 mm/swap.c:1103
 __pagevec_release+0x71/0xe0 mm/swap.c:1123
 pagevec_release include/linux/pagevec.h:88 [inline]
 __invalidate_mapping_pages+0x90a/0x9e0 mm/truncate.c:607
 invalidate_mapping_pages+0x27/0x30 mm/truncate.c:632
 invalidate_bdev+0xa3/0x140 fs/block_dev.c:97
 ext4_put_super+0x669/0x9c0 fs/ext4/super.c:1237
 generic_shutdown_super+0x149/0x320 fs/super.c:465
 kill_block_super+0x7f/0xf0 fs/super.c:1469
 deactivate_locked_super+0xa0/0x100 fs/super.c:335
 deactivate_super+0xaf/0xe0 fs/super.c:366
 cleanup_mnt+0x45b/0x510 fs/namespace.c:1123
 __cleanup_mnt+0x19/0x20 fs/namespace.c:1130
 task_work_run+0x127/0x190 kernel/task_work.c:189
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop+0xcb/0xe0 kernel/entry/common.c:172

Memory state around the buggy address:
 ffff888130b69680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888130b69700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888130b69780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                                       ^
 ffff888130b69800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888130b69880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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