dm-era: fix shadowed superblock leak on take-snap failure (CVE-2026-89576) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89576

dm-era: fix shadowed superblock leak on take-snap failure

Answer in brief

CVE-2026-89576 records a Unknown severity vulnerability in dm-era: fix shadowed superblock leak on take-snap failure. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=eec40579d84873dfb7021eb24c50360f073237c5 <d66ceeefb87ddb097b0546bafc581380b816b048 \|\| >=eec40579d84873dfb7021eb24c50360f073237c5 <36ff918637e3517f732188a3c39dbeae5b9cfb1b \|\| >=eec40579d84873dfb7021eb24c50360f073237c5 <6876ca330e741fb8886d12070cb6a7f9cb67257e \|\| >=eec40579d84873dfb7021eb24c50360f073237c5 <39c5aa3bd8ec3912d2cd0b3fe092642b0d2b0713	d66ceeefb87ddb097b0546bafc581380b816b048, 36ff918637e3517f732188a3c39dbeae5b9cfb1b, 6876ca330e741fb8886d12070cb6a7f9cb67257e, 39c5aa3bd8ec3912d2cd0b3fe092642b0d2b0713
Linux/Linuxgeneric	3.15	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to d66ceeefb87ddb097b0546bafc581380b816b048 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: dm-era: fix shadowed superblock leak on take-snap failure metadata_take_snap() bumps the live superblock refcount and then dm_tm_shadow_block() allocates a new block for the metadata snapshot. If the subsequent dm_sm_inc_block() of writeset_tree_root or era_array_root fails, the function only unlocks the clone and returns. The newly allocated shadow block is never returned to the metadata space map, so each failed take-snap permanently leaks one metadata block. Free the clone with dm_sm_dec_block() on those error paths, matching the final step of metadata_drop_snap().

Quoted source text, attributed separately from HOL analysis.