diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
index e18e80e832fd..175208d712b0 100644
--- a/drivers/hwmon/occ/common.c
+++ b/drivers/hwmon/occ/common.c
@@ -1052,32 +1052,49 @@ static int occ_setup_sensor_attrs(struct occ *occ)
 }
 
 /* only need to do this once at startup, as OCC won't change sensors on us */
-static void occ_parse_poll_response(struct occ *occ)
+static int occ_parse_poll_response(struct occ *occ)
 {
 	unsigned int i, old_offset, offset = 0, size = 0;
+	u16 data_length;
 	struct occ_sensor *sensor;
-	struct occ_sensors *sensors = &occ->sensors;
+	struct occ_sensors parsed = {};
+	struct occ_sensors *sensors = &parsed;
 	struct occ_response *resp = &occ->resp;
 	struct occ_poll_response *poll =
 		(struct occ_poll_response *)&resp->data[0];
 	struct occ_poll_response_header *header = &poll->header;
 	struct occ_sensor_data_block *block = &poll->block;
 
+	data_length = get_unaligned_be16(&resp->data_length);
+	if (data_length < sizeof(*header) || data_length > OCC_RESP_DATA_BYTES) {
+		dev_err(occ->bus_dev, "invalid OCC poll response length %u\n",
+			data_length);
+		return -EMSGSIZE;
+	}
+
 	dev_info(occ->bus_dev, "OCC found, code level: %.16s\n",
 		 header->occ_code_level);
 
 	for (i = 0; i < header->num_sensor_data_blocks; ++i) {
 		block = (struct occ_sensor_data_block *)((u8 *)block + offset);
+		if (size + sizeof(*header) + sizeof(block->header) >
+		    data_length) {
+			dev_err(occ->bus_dev,
+				"truncated OCC sensor block header\n");
+			return -EMSGSIZE;
+		}
+
 		old_offset = offset;
 		offset = (block->header.num_sensors *
 			  block->header.sensor_length) + sizeof(block->header);
-		size += offset;
 
 		/* validate all the length/size fields */
-		if ((size + sizeof(*header)) >= OCC_RESP_DATA_BYTES) {
-			dev_warn(occ->bus_dev, "exceeded response buffer\n");
-			return;
+		if (size + sizeof(*header) + offset > data_length) {
+			dev_err(occ->bus_dev,
+				"exceeded OCC poll response length\n");
+			return -EMSGSIZE;
 		}
+		size += offset;
 
 		dev_dbg(occ->bus_dev, " %04x..%04x: %.4s (%d sensors)\n",
 			old_offset, offset - 1, block->header.eye_catcher,
@@ -1107,6 +1124,9 @@ static void occ_parse_poll_response(struct occ *occ)
 
 	dev_dbg(occ->bus_dev, "Max resp size: %u+%zd=%zd\n", size,
 		sizeof(*header), size + sizeof(*header));
+	occ->sensors = parsed;
+
+	return 0;
 }
 
 int occ_active(struct occ *occ, bool active)
@@ -1138,10 +1158,12 @@ int occ_active(struct occ *occ, bool active)
 			goto unlock;
 		}
 
-		occ->active = true;
 		occ->next_update = jiffies + OCC_UPDATE_FREQUENCY;
-		occ_parse_poll_response(occ);
+		rc = occ_parse_poll_response(occ);
+		if (rc)
+			goto unlock;
 
+		occ->active = true;
 		rc = occ_setup_sensor_attrs(occ);
 		if (rc) {
 			dev_err(occ->bus_dev,