cgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode()
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 7.2.11
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The Linux kernel's cpuset cgroup controller, which manages CPU and memory placement for process groups, is affected. A race condition during cgroup filesystem rebinding could let the kernel read a stale pointer, potentially causing a use-after-free that may lead to a crash or memory corruption.
Summarized by anthropic/claude-haiku-5.5. Verify details against the original sources.
Read the original description
In the Linux kernel, the following vulnerability has been resolved: cgroup/cpuset: Don't access cpuset_cgrp_subsys.root in is_in_v2_mode() After seeing the patch [1] to guard is_in_v2_mode() with RCU, it makes me realize that is_in_v2_mode() may be called in a context where a new cgroup filesystem is being rebound with stale cpuset_cgrp_subsys.root pointer. Avoid this potential UaF situation by adding a new cpuset_v2_mode flag which is set when the cpuset_v2_mode mount option is used. This flag is written into only when cpuset_bind() is being called with a stable cpuset_cgrp_subsys.root value. The is_in_v2_mode() helper is modified to read the new cpuset_v2_mode flag instead of accessing cpuset_cgrp_subsys.root directly. [1] https://lore.kernel.org/lkml/20260929084124.626693-2-arighi@nvidia.com
Timeline
- CVE published
- First seen by cve.now
Affected versions
- Linux Linux
From b8d1b8ee93df8ffbabbeadd65d39853cfad6d698 · fixed in 988bf67a13890a37a33201f95947095ca9bec856; From b8d1b8ee93df8ffbabbeadd65d39853cfad6d698 · fixed in e06b678e3b4e12fdaa0b51a7a5a54abc5dbd6469
- Linux Linux
4.14
- KernelLinux
From 4.14.0 · fixed in 7.2.11