cve-2024-35985
Vulnerability from cvelistv5
Published
2024-05-20 09:47
Modified
2024-12-19 08:59
Severity ?
Summary
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.
References
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35c
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fe
416baaa9-dc9f-4396-8d5f-8c081fb06d67https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efb
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35c
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fe
af854a3a-2127-422b-91ae-364da2661108https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efb
Impacted products
Vendor Product Version
Linux Linux Version: 6.7
Show details on NVD website

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