Answer in brief
CVE-2026-90326 records a Unknown severity vulnerability in blk-cgroup: fix race between policy activation and blkg destruction. 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.
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.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=81c1188905f88b77743d1fdeeedfc8cb7b67787d <b5dae1cd0d8368b4338430ff93403df67f0b8bcc || >=bfe46d2efe46c5c952f982e2ca94fe2ec5e58e2a <083b58373463a6e5ee60ecb135269348f68ad7df || >=f1c006f1c6850c14040f8337753a63119bba39b9 <ac34e655dffa74349d885a43d098115336f53842 || >=f1c006f1c6850c14040f8337753a63119bba39b9 <2cf9f50a38c1839e549a08e22aa35e8d69e2c8fd || >=f1c006f1c6850c14040f8337753a63119bba39b9 <5313d4d41739b0cb63000747c97bb1217ac45f3e || >=6.1.16 <6.1.17 || >=6.2.3 <6.2.4 | b5dae1cd0d8368b4338430ff93403df67f0b8bcc, 083b58373463a6e5ee60ecb135269348f68ad7df, ac34e655dffa74349d885a43d098115336f53842, 2cf9f50a38c1839e549a08e22aa35e8d69e2c8fd, 5313d4d41739b0cb63000747c97bb1217ac45f3e, 6.1.17, 6.2.4 |
| Linux/Linuxgeneric | 6.3 | Not reported |
Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 17, 2026
In the Linux kernel, the following vulnerability has been resolved: blk-cgroup: fix race between policy activation and blkg destruction When switching an IO scheduler on a block device, blkcg_activate_policy() allocates blkg_policy_data (pd) for all blkgs attached to the queue. However, blkcg_activate_policy() may race with concurrent blkcg deletion, leading to use-after-free and memory leak issues. The use-after-free occurs in the following race: T1 (blkcg_activate_policy): - Successfully allocates pd for blkg1 (loop0->queue, blkcgA) - Fails to allocate pd for blkg2 (loop0->queue, blkcgB) - Enters the enomem rollback path to release blkg1 resources T2 (blkcg deletion): - blkcgA is deleted concurrently - blkg1 is freed via blkg_free_workfn() - blkg1->pd is freed T1 (continued): - Rollback path accesses blkg1->pd->online after pd is freed - Triggers use-after-free In addition, blkg_free_workfn() frees pd before removing the blkg from q->blkg_list. This allows blkcg_activate_policy() to allocate a new pd for a blkg that is being destroyed, leaving the newly allocated pd unreachable when the blkg is finally freed. Fix these races by extending blkcg_mutex coverage to serialize blkcg_activate_policy() rollback and blkg destruction, ensuring pd lifecycle is synchronized with blkg list visibility.
Quoted source text, attributed separately from HOL analysis.