CVE-2026-64532 PUBLISHED

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

Assigner: Linux
Reserved: 19.07.2026 Published: 27.07.2026 Updated: 27.07.2026

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" (20260502105008.21827-1-jhapavitra98@gmail.com) which proposes calling ntfs3_bad_de_range(); that helper does not exist in mainline. This patch uses inline checks.

Product Status

Vendor Linux
Product Linux
Versions Default: unaffected
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to b20e5a709d8bd190d6e4645606763c7423e694c1 (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to d41b382068ca4e64e421f736cdd700095464b6ac (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to 429d653ca641d38a78609b8f62e81a0a5c780a2d (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to 315d3a9a48b49f889da3d858a9307e677cb9e1bd (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to be306b8d9143a9c076c804a7ca025d69caf9c448 (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to 36feda687afebae24c472202694448738809c411 (excl.)
  • affected from b46acd6a6a627d876898e1c84d3f84902264b445 to 3e127829e57f5190f612412ece4541cb96d5ec7a (excl.)
Vendor Linux
Product Linux
Versions Default: affected
  • Version 5.15 is affected
  • unaffected from 0 to 5.15 (excl.)
  • unaffected from 5.15.212 to 5.15.* (incl.)
  • unaffected from 6.1.178 to 6.1.* (incl.)
  • unaffected from 6.6.145 to 6.6.* (incl.)
  • unaffected from 6.12.97 to 6.12.* (incl.)
  • unaffected from 6.18.40 to 6.18.* (incl.)
  • unaffected from 7.1.5 to 7.1.* (incl.)
  • unaffected from 7.2-rc1 to * (incl.)

References