ntfs: Fix index_root heap OOB write in ntfs_ir_to_ib()
Summary
| CVE | CVE-2026-90133 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-17 17:17:05 UTC |
| Updated | 2026-09-17 17:17:05 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
ntfs: Fix index_root heap OOB write in ntfs_ir_to_ib()
ntfs_ir_to_ib copies all entries from index_root into a freshly allocated
index_block_size-byte buffer without verifying that the entries fit in the
available space. The entries in index_root may be larger than the usable
entry space in the index block.
This can cause OOB writes past the end of the allocation.
The validator ntfs_index_root_inconsistent() checks that entries are
self-consistent within the IR value, but never cross-checks them against
index_block_size. There is no bounds check in ntfs_ir_to_ib() before the
memcpy.
Fixing this at the sink in ntfs_ir_to_ib() since
ntfs_index_root_inconsistent() validates the logical consistency of
index_root as a structure and a root with large entries is a structurally
valid root. The bug is a size conflict of ntfs_ir_to_ib().
Also, the validator is called once per inode load in
ntfs_read_locked_inode() while ntfs_ir_to_ib() is only called during a
reparent, a check there adds no overhead to the common path.
Moreover, even a future call path that bypasses the validator would still
be protected.
With NULL as first parameter of ntfs_error(), the volume error flag is
never set by this call, so the device name will be absent from the error
message. In any case, that the caller, ntfs_ir_reparent(), prints an error
message that includes the device name on NULL returns.
I think this is the best solution available without adding
'struct super_block *sb' as a parameter to ntfs_ir_to_ib().
This heap out-of-bounds write is triggered by a crafted filesystem image,
which is not in the kernel threat model, anyway, fixing memory errors would
be nice to keep things secure. |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 0a8ac0c1fa0b99a5b29002bc7f232ed7eafddef0 825dec5120933e90c54e30e31ccfa6c3449043a8 git |
Not specified |
| CNA |
Linux |
Linux |
affected 0a8ac0c1fa0b99a5b29002bc7f232ed7eafddef0 dc09bf79b76f9a7157e225f449655f3f62f96c9c git |
Not specified |
| CNA |
Linux |
Linux |
affected 7.1 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.1 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.2.6 7.2.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.3-rc1 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/825dec5120933e90c54e30e31ccfa6c3449043a8 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/dc09bf79b76f9a7157e225f449655f3f62f96c9c |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.