CVE-2021-47368

In the Linux kernel, the following vulnerability has been resolved:

enetc: Fix illegal access when reading affinity_hint

irqsetaffinityhit() stores a reference to the cpumaskt parameter in the irq descriptor, and that reference can be accessed later from irqaffinityhintprocshow(). Since the cpumask parameter passed to irqsetaffinityhit() has only temporary storage (it's on the stack memory), later accesses to it are illegal. Thus reads from the corresponding procfs affinity_hint file can result in paging request oops.

The issue is fixed by the getcpumask() helper, which provides a permanent storage for the cpumask_t parameter.