diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index 56bb840142e3f8567032b9e8cb1ac6df7ed99c05..f5c9787992e96d520cc884e88d06eb0c179c10a3 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -495,6 +495,13 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
 			break;
 		case I2C_SMBUS_BLOCK_DATA:
 		case I2C_SMBUS_BLOCK_PROC_CALL:
+			if (msg[1].buf[0] > I2C_SMBUS_BLOCK_MAX) {
+				dev_err(&adapter->dev,
+					"Invalid block size returned: %d\n",
+					msg[1].buf[0]);
+				status = -EPROTO;
+				goto cleanup;
+			}
 			for (i = 0; i < msg[1].buf[0] + 1; i++)
 				data->block[i] = msg[1].buf[i];
 			break;