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

HID: bpf: prevent buffer overflow in hid_hw_request

right now the returned value is considered to be always valid. However,
when playing with HID-BPF, the return value can be arbitrary big,
because it's the return value of dispatch_hid_bpf_raw_requests(), which
calls the struct_ops and we have no guarantees that the value makes
sense.