Answer in brief
CVE-2026-90326 records a High severity (CVSS 7.8) 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), 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.
CVSS is 7.8. 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), 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 |
| Linux/Linuxgeneric | >=81c1188905f88b77743d1fdeeedfc8cb7b67787d <b5dae1cd0d8368b4338430ff93403df67f0b8bcc || >=bfe46d2efe46c5c952f982e2ca94fe2ec5e58e2a <083b58373463a6e5ee60ecb135269348f68ad7df || >=f1c006f1c6850c14040f8337753a63119bba39b9 <17c18a0df70c2b89ff7fcd74622f1540e98d00fd || >=f1c006f1c6850c14040f8337753a63119bba39b9 <91062e3a9ed251726df4e20ff9a1113f1c8ded59 || >=f1c006f1c6850c14040f8337753a63119bba39b9 <ac34e655dffa74349d885a43d098115336f53842 || >=f1c006f1c6850c14040f8337753a63119bba39b9 <2cf9f50a38c1839e549a08e22aa35e8d69e2c8fd || >=f1c006f1c6850c14040f8337753a63119bba39b9 <5313d4d41739b0cb63000747c97bb1217ac45f3e || >=6.1.16 <6.1.17 || >=6.2.3 <6.2.4 | b5dae1cd0d8368b4338430ff93403df67f0b8bcc, 083b58373463a6e5ee60ecb135269348f68ad7df, 17c18a0df70c2b89ff7fcd74622f1540e98d00fd, 91062e3a9ed251726df4e20ff9a1113f1c8ded59, ac34e655dffa74349d885a43d098115336f53842, 2cf9f50a38c1839e549a08e22aa35e8d69e2c8fd, 5313d4d41739b0cb63000747c97bb1217ac45f3e, 6.1.17, 6.2.4 |
Published upstream
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 21, 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.