Executive brief
In the Linux kernel, the following vulnerability has been resolved:
bpf: mark a NULL call argument precise
check_func_arg() allows bpf_register_is_null() for nullable arguments w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value.
check_helper_call() enforces second parameter of the bpf_get_local_storage() to be zero, w/o marking the underlying scalar register precise. Hence a checkpoint created on such a path would prune against arbitrary scalar value.
Grouping these two into one patch, as they share the same fixes tag.