dm-integrity: fix buffer overflow with keyed discard
Summary
| CVE | CVE-2026-90052 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-17 17:16:53 UTC |
| Updated | 2026-09-17 17:16:53 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
dm-integrity: fix buffer overflow with keyed discard
Since commit 68c5c42567bc ("dm-integrity: replace forgeable discard
filler with a keyed sector marker"), integrity_metadata computes a
checksum for every discarded block into the "checksums" buffer.
integrity_sector_checksum always writes the whole digest. So if the tag
size is smaller than the digest size, the checksum of the last block
that fits into the buffer is written past the end of it. For example,
with hmac(sha256) and tag size 16, a 4MiB discard writes 16 bytes past
the kmalloc'ed page.
Fix this by subtracting extra_space from the buffer size when computing
max_blocks, like we do for writes. |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected 5c58ea19a909ef6bed4f0f824e9cd7e30d7e4775 9988c1c9e0d1c78391e3d8e2817beb667470c76f git |
Not specified |
| CNA |
Linux |
Linux |
affected 6228722c27304e4682cddc1fede03898f87e4414 dd08a645195f410f2dcaa40de379a45ce110e873 git |
Not specified |
| CNA |
Linux |
Linux |
affected 68c5c42567bc462139128968ebbfadd0aefff519 59e6f919d77d72ec79cbf171256f2f7819737580 git |
Not specified |
| CNA |
Linux |
Linux |
affected 7.3-rc1 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.3-rc1 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.3-rc2 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/9988c1c9e0d1c78391e3d8e2817beb667470c76f |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/dd08a645195f410f2dcaa40de379a45ce110e873 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/59e6f919d77d72ec79cbf171256f2f7819737580 |
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.