spi: spidev: use memdup_user

Use memdup_user() helper instead of open-coding to simplify the code.

Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spidev.c b/drivers/spi/spidev.c
index 3b57001..d4d2d8d 100644 (file)
--- a/drivers/spi/spidev.c
+++ b/drivers/spi/spidev.c
@@ -324,7 +324,6 @@ static struct spi_ioc_transfer *
 spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc,
                unsigned *n_ioc)
 {
-       struct spi_ioc_transfer *ioc;
        u32     tmp;
 
        /* Check type, command number and direction */
@@ -341,14 +340,7 @@ spidev_get_ioc_message(unsigned int cmd, struct spi_ioc_transfer __user *u_ioc,
                return NULL;
 
        /* copy into scratch area */
-       ioc = kmalloc(tmp, GFP_KERNEL);
-       if (!ioc)
-               return ERR_PTR(-ENOMEM);
-       if (__copy_from_user(ioc, u_ioc, tmp)) {
-               kfree(ioc);
-               return ERR_PTR(-EFAULT);
-       }
-       return ioc;
+       return memdup_user(u_ioc, tmp);
 }
 
 static long