Matthieu

**Name of the Vulnerable Software and Affected Versions** Linux kernel (affected versions not specified) **Description** An issue exists in the `sched/mmcid` component regarding the handling of `vfork()` and `CLONE VM`. A logic error occurs when the number of tasks associated with a process is smaller than the number of MMCID users. The system incorrectly accounts for already processed tasks while searching the task list for a `vfork()`ed task. If this leads to the number of tasks to be handled reaching zero, the walk stops without fixing the `vfork()`ed task's CID. This results in a failure to acquire a transitional CID during a subsequent schedule in, causing the machine to stall. This can lead to a state where a task endlessly loops in the `mm get cid()` function. **Recommendations** At the moment, there is no information about a newer version that contains a fix for this vulnerability.