[PATCH 0/3] ntfs: harden MFT record and attribute parsing
From: DaeMyung Kang
Date: Fri May 08 2026 - 11:37:07 EST
This series tightens fs/ntfs against malformed on-disk metadata and
fixes one off-by-one in the MFT bitmap scan.
Patches 1/3 and 3/3 are complementary: 1/3 rejects MFT records whose
attrs_offset points past bytes_in_use at record entry, and 3/3 moves
the per-attribute name bounds check earlier so it covers the AT_UNUSED
enumeration path that hands the name pointer back to callers. Without
3/3, two enumeration paths can read past an attribute record: one in
fs/ntfs/attrib.c passes the returned name pointer to ntfs_attr_iget(),
and another in fs/ntfs/inode.c copies the name while building an
attribute list.
Patch 2/3 is independent: ntfs_mft_record_layout() rejects
mft_no >= 2^32, but the bitmap scan in
ntfs_mft_bitmap_find_and_alloc_free_rec_nolock() used '>'. Bring it in
line with the other 2^32 boundary checks in fs/ntfs/mft.c.
All three carry the same Fixes tag (d3ad708fecaa) since the issues
date from the initial fs/ntfs commit in this tree.
DaeMyung Kang (3):
ntfs: validate MFT attrs_offset against bytes_in_use
ntfs: fix MFT bitmap scan 2^32 boundary check
ntfs: validate attribute name bounds before returning it
fs/ntfs/attrib.c | 25 +++++++++++++++++--------
fs/ntfs/mft.c | 16 ++++++++++++++--
2 files changed, 31 insertions(+), 10 deletions(-)
--
2.34.1