[U-Boot] [PATCH 3/3] spi: fsl_quadspi: Fix qspi_op_rdid memcpy issue

[Gong Qianyu]

In current driver everytime we memcpy 4 bytes to the dest memory
regardless of the remaining length.
This patch add checking the remaining length before memcpy.
If the length is shorter than 4 bytes, memcpy the actual length of data
to the dest memory.

Signed-off-by: Gong Qianyu <Qianyu.Gong at freescale.com>
---
 drivers/spi/fsl_qspi.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/spi/fsl_qspi.c b/drivers/spi/fsl_qspi.c
index 755cc27..b41b226 100644
--- a/drivers/spi/fsl_qspi.c
+++ b/drivers/spi/fsl_qspi.c
@@ -499,7 +499,10 @@ static void qspi_op_rdid(struct fsl_qspi_priv *priv, u32 *rxbuf, u32 len)
 		if (rbsr_reg & QSPI_RBSR_RDBFL_MASK) {
 			data = qspi_read32(priv->flags, &regs->rbdr[i]);
 			data = qspi_endian_xchg(data);
-			memcpy(rxbuf, &data, 4);
+			if (size < 4)
+				memcpy(rxbuf, &data, size);
+			else
+				memcpy(rxbuf, &data, 4);
 			rxbuf++;
 			size -= 4;
 			i++;
-- 
2.1.0.27.g96db324