CVE-2026-43438
Description
AI Translation Available
In the Linux kernel, the following vulnerability has been resolved:
sched_ext: Remove redundant css_put() in scx_cgroup_init()
The iterator css_for_each_descendant_pre() walks the cgroup hierarchy
under cgroup_lock(). It does not increment the reference counts on
yielded css structs.
According to the cgroup documentation, css_put() should only be used
to release a reference obtained via css_get() or css_tryget_online().
Since the iterator does not use either of these to acquire a reference,
calling css_put() in the error path of scx_cgroup_init() causes a
refcount underflow.
Remove the unbalanced css_put() to prevent a potential Use-After-Free
(UAF) vulnerability.
https://git.kernel.org/stable/c/1336b579f6079fb8520be03624fcd9ba443c930b
https://git.kernel.org/stable/c/6eaaa67d6998f6c30c462b140db8c062e07ec473
https://git.kernel.org/stable/c/bf50f3285eda8a0173625fcdb5f183f96e1008cd
https://git.kernel.org/stable/c/cc095cd305fddbe25a968e4a78436ff9476cf0f6