CVE-2024-35985
In the Linux kernel, the following vulnerability has been resolved: sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref.
Does this matter?
Lower severity and a low EPSS score (0.23%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf() It was possible to have pick_eevdf() return NULL, which then causes a NULL-deref. This turned out to be due to entity_eligible() returning falsely negative because of a s64 multiplcation overflow. Specifically, reweight_eevdf() computes the vlag without considering the limit placed upon vlag as update_entity_lag() does, and then the scaling multiplication (remember that weight is 20bit fixed point) can overflow. This then leads to the new vruntime being weird which then causes the above entity_eligible() to go side-ways and claim nothing is eligible. Thus limit the range of vlag accordingly. All this was quite rare, but fatal when it does happen.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.23% probability · 13th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35cPatch
- https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fePatch
- https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efbPatch
- https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35cPatch
- https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fePatch
- https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efbPatch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.