In the Linux kernel, the following vulnerability has been resolved:
blk-mq: set RQF_USE_SCHED when the operation is known
The cached requests are allocated for one operation but can be handed
out for another. A passthrough command has RQF_USE_SCHED cleared, so
using those flags for a subsequent read/write bio will insert it into
the scheduler without ->prepare_request() and frees it without
->finish_request(). For kyber, this leaks the domain token acquired at
dispatch and stalls the queue.
Don't set RQF_USE_SCHED based on the first operation the batch happened
to be allocated for. Instead, set it after the request is claimed by an
operation. Introduce a helper function, blk_mq_rq_late_init() for this,
and absorb blk_mq_rq_time_init() since the two run together.
blk-mq: set RQF_USE_SCHED when the operation is known
The cached requests are allocated for one operation but can be handed
out for another. A passthrough command has RQF_USE_SCHED cleared, so
using those flags for a subsequent read/write bio will insert it into
the scheduler without ->prepare_request() and frees it without
->finish_request(). For kyber, this leaks the domain token acquired at
dispatch and stalls the queue.
Don't set RQF_USE_SCHED based on the first operation the batch happened
to be allocated for. Instead, set it after the request is claimed by an
operation. Introduce a helper function, blk_mq_rq_late_init() for this,
and absorb blk_mq_rq_time_init() since the two run together.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Sun, 18 Oct 2026 21:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-665 |
Sun, 18 Oct 2026 16:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: blk-mq: set RQF_USE_SCHED when the operation is known The cached requests are allocated for one operation but can be handed out for another. A passthrough command has RQF_USE_SCHED cleared, so using those flags for a subsequent read/write bio will insert it into the scheduler without ->prepare_request() and frees it without ->finish_request(). For kyber, this leaks the domain token acquired at dispatch and stalls the queue. Don't set RQF_USE_SCHED based on the first operation the batch happened to be allocated for. Instead, set it after the request is claimed by an operation. Introduce a helper function, blk_mq_rq_late_init() for this, and absorb blk_mq_rq_time_init() since the two run together. | |
| Title | blk-mq: set RQF_USE_SCHED when the operation is known | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-18T15:49:12.251Z
Reserved: 2026-09-25T10:25:14.372Z
Link: CVE-2026-98820
No data.
Status : Received
Published: 2026-10-18T16:17:36.240
Modified: 2026-10-18T16:17:36.240
Link: CVE-2026-98820
No data.
OpenCVE Enrichment
Updated: 2026-10-18T21:30:14Z
Weaknesses