Ran Xiaokai

**Name of the Vulnerable Software and Affected Versions** Linux kernel versions prior to 6.6.74 **Description** A vulnerability in the Linux kernel has been resolved. The issue is related to the KCSAN reporting logic, which checks if it should filter a report on a detected data race. The report filterlist lock spinlock, which protects this list, may sleep on RT kernels. To fix this, the report filterlist lock has been converted to a raw spinlock. This change requires careful memory allocation for the filter list, which can be done via KCSAN's debugfs interface. **Recommendations** To resolve the issue, update to Linux kernel version 6.6.74 or later. As a temporary workaround, consider disabling the KCSAN debugfs interface to minimize the risk of exploitation. Restrict access to the debugfs interface to prevent concurrent modification of the filter list. Avoid using the report filterlist lock spinlock in any context where it may sleep on RT kernels.

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** The issue occurs when a system has isolated CPUs via the "isolcpus=" command line parameter, and an attempt is made to offline the last housekeeping CPU. This results in a WARN ON() when rebuilding the scheduler domains and a subsequent panic due to an unhandled empty CPU mask in partition sched domains locked(). The functions `cpuset hotplug workfn()` and `rebuild sched domains locked()` are involved in this process. The `cpumask and()` function is used with `doms[0]`, `top cpuset.effective cpus`, and `housekeeping cpumask(HK FLAG DOMAIN)`. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.