5.5

CVE-2024-35985

sched/eevdf: Prevent vlag from going out of bounds in reweight_eevdf()

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
LinuxLinux Kernel Version >= 6.6.4 < 6.6.30
LinuxLinux Kernel Version >= 6.7 < 6.8.9
LinuxLinux Kernel Version6.9 Updaterc1
LinuxLinux Kernel Version6.9 Updaterc2
LinuxLinux Kernel Version6.9 Updaterc3
LinuxLinux Kernel Version6.9 Updaterc4
LinuxLinux Kernel Version6.9 Updaterc5
VulnDex Vulnerability Enrichment
Diese Information steht angemeldeten Benutzern zur Verfügung. Login Login
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.23% 0.129
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
nvd@nist.gov 5.5 1.8 3.6
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
CWE-476 NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

https://git.kernel.org/stable/c/06f27e6d7bf0abf54488259ef36bbf0e1fccb35c
Patch
https://git.kernel.org/stable/c/1560d1f6eb6b398bddd80c16676776c0325fe5fe
Patch
https://git.kernel.org/stable/c/470d347b14b0ecffa9b39cf8f644fa2351db3efb
Patch