Kernel-memory disclosure via uninitialized netdevsim map values

Information disclosure in Linux Kernel netdevsim before 5.16-rc6 allows local users to read kernel heap data through BPF map lookup. nsim_map_alloc_elem allocates array-map values with kmalloc without zeroing them, and map_lookup_elem later copies the uninitialized bytes to user space. A low-privileged local user must be able to create and query an offloaded BPF array map; the result is disclosure of residual kernel-memory contents.