@@ -78,12 +78,16 @@ EXPORT_SYMBOL_GPL(trace_call_bpf);
BPF_CALL_3(bpf_probe_read, void *, dst, u32, size, const void *, unsafe_ptr)
{
- int ret;
+ int ret = 0;
+
+ if (unlikely(size == 0))
+ goto out;
ret = probe_kernel_read(dst, unsafe_ptr, size);
if (unlikely(ret < 0))
memset(dst, 0, size);
+ out:
return ret;
}
@@ -92,7 +96,7 @@ static const struct bpf_func_proto bpf_probe_read_proto = {
.gpl_only = true,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_UNINIT_MEM,
- .arg2_type = ARG_CONST_SIZE,
+ .arg2_type = ARG_CONST_SIZE_OR_ZERO,
.arg3_type = ARG_ANYTHING,
};