platform/chrome: cros_ec_i2c: drop BUG_ON() in cros_ec_pkt_xfer_i2c()

It is overkill to crash the kernel if the given message is oversize.

Drop the BUG_ON() and return -EINVAL instead.

Reviewed-by: Guenter Roeck <groeck@chromium.org>
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Link: https://lore.kernel.org/r/20220513044143.1045728-6-tzungbi@kernel.org

Author: Tzung-Bi Shih

drivers/platform/chrome/cros_ec_i2c.c

@@ -72,13 +72,19 @@ static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
 	i2c_msg[1].flags = I2C_M_RD;
 
 	packet_len = msg->insize + response_header_size;
-	BUG_ON(packet_len > ec_dev->din_size);
+	if (packet_len > ec_dev->din_size) {
+		ret = -EINVAL;
+		goto done;
+	}
 	in_buf = ec_dev->din;
 	i2c_msg[1].len = packet_len;
 	i2c_msg[1].buf = (char *) in_buf;
 
 	packet_len = msg->outsize + request_header_size;
-	BUG_ON(packet_len > ec_dev->dout_size);
+	if (packet_len > ec_dev->dout_size) {
+		ret = -EINVAL;
+		goto done;
+	}
 	out_buf = ec_dev->dout;
 	i2c_msg[0].len = packet_len;
 	i2c_msg[0].buf = (char *) out_buf;