@@ -528,6 +528,16 @@ static int cxl_cdat_read_table(struct device *dev,
return 0;
}
+static unsigned char cdat_checksum(void *buf, size_t size)
+{
+ unsigned char sum, *data = buf;
+ size_t i;
+
+ for (sum = 0, i = 0; i < size; i++)
+ sum += data[i];
+ return sum;
+}
+
/**
* read_cdat_data - Read the CDAT data on this port
* @port: Port to read data from
@@ -567,15 +577,21 @@ void read_cdat_data(struct cxl_port *port)
return;
rc = cxl_cdat_read_table(dev, cdat_doe, cdat_table, &cdat_length);
- if (rc) {
- /* Don't leave table data allocated on error */
- devm_kfree(dev, cdat_table);
- dev_err(dev, "CDAT data read error\n");
- return;
- }
+ if (rc)
+ goto err;
- port->cdat.table = cdat_table + sizeof(__le32);
+ cdat_table = cdat_table + sizeof(__le32);
+ if (cdat_checksum(cdat_table, cdat_length))
+ goto err;
+
+ port->cdat.table = cdat_table;
port->cdat.length = cdat_length;
+ return;
+
+err:
+ /* Don't leave table data allocated on error */
+ devm_kfree(dev, cdat_table);
+ dev_err(dev, "Failed to read/validate CDAT.\n");
}
EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL);