CVE-2026-64532

In the Linux kernel, the following vulnerability has been resolved:

fs/ntfs3: bound NTFS_DE view.data_off in UpdateRecordData{Root,Allocation}

In do_action()'s UpdateRecordDataRoot (fslog.c:3489) and

UpdateRecordDataAllocation (fslog.c:3697) cases, the memmove

destination is `Add2Ptr(e, le16_to_cpu(e->view.data_off))`,

where e->view.data_off comes from an on-disk NTFS_DE inside

an INDEX_ROOT or INDEX_BUFFER. Neither case validates

view.data_off + dlen against e->size; the existing

check_if_index_root / check_if_alloc_index helpers walk the

entry chain and validate the entry's offset, but not its

internal view fields.

The neighbouring read sites (e.g., fs/ntfs3/index.c when

iterating view entries) check view.data_off + view.data_size

<= e->size. Apply the same bound at the two memmove sites.

Reproduced under UML+KASAN on mainline 8d90b09e6741 via

pr_warn-only probe instrumentation: with view.data_off forced

to 0xFFFC, the memmove writes 32 bytes past the end of the

NTFS_DE.

This is similar in shape to Pavitra Jha's 2026-05-02 patch

"fs/ntfs3: prevent oob in case UpdateRecordDataRoot"

(<[email protected]>) which

proposes calling ntfs3_bad_de_range(); that helper does not

exist in mainline. This patch uses inline checks.