ntfs: fix off-by-one page overflow in ntfs_decompress()
The per-token range check in ntfs_decompress() uses
if (cb >= cb_sb_end || dp_addr > dp_sb_end)
break;
so dp_addr == dp_sb_end falls through to the symbol copy
`*dp_addr++ = *cb++`, writing one byte past the destination page. Since
NTFS_SB_SIZE == PAGE_SIZE the destination is a single page, so the byte
lands in the adjacent page, and *dest_ofs is left one past the sub-block
end (the later `*dest_ofs &= ~PAGE_MASK` then yields 1, not 0, so the page
is never finalized and later sub-blocks keep writing further past it). A
corrupted compressed $DATA attribute thus produces a bounded run of
out-of-bounds writes when the file is read.
Break as soon as dp_addr reaches dp_sb_end; a full sub-block still
completes, as its final copy advances dp_addr to exactly dp_sb_end.
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
|||||||||||||||
| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
No advisories yet.
Thu, 17 Sep 2026 16:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: ntfs: fix off-by-one page overflow in ntfs_decompress() The per-token range check in ntfs_decompress() uses if (cb >= cb_sb_end || dp_addr > dp_sb_end) break; so dp_addr == dp_sb_end falls through to the symbol copy `*dp_addr++ = *cb++`, writing one byte past the destination page. Since NTFS_SB_SIZE == PAGE_SIZE the destination is a single page, so the byte lands in the adjacent page, and *dest_ofs is left one past the sub-block end (the later `*dest_ofs &= ~PAGE_MASK` then yields 1, not 0, so the page is never finalized and later sub-blocks keep writing further past it). A corrupted compressed $DATA attribute thus produces a bounded run of out-of-bounds writes when the file is read. Break as soon as dp_addr reaches dp_sb_end; a full sub-block still completes, as its final copy advances dp_addr to exactly dp_sb_end. | |
| Title | ntfs: fix off-by-one page overflow in ntfs_decompress() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-09-17T16:06:23.333Z
Reserved: 2026-09-11T19:38:34.787Z
Link: CVE-2026-90118
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-09-17T17:17:03.963
Modified: 2026-09-17T17:17:03.963
Link: CVE-2026-90118
Redhat
No data.
OpenCVE Enrichment
No data.
No weakness.