media: media/usb: Use kmemdup rather than duplicating its implementation

kmemdup is introduced to duplicate a region of memory in a neat way.
Rather than kmalloc/kzalloc + memcpy, which the programmer needs to
write the size twice (sometimes lead to mistakes), kmemdup improves
readability, leads to smaller code and also reduce the chances of mistakes.
Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c
index 1283c7ca9ad51a4fa399d81a107aeea14703b209..6e33782c3ca659d3d08acfe06bfa9a54b5d415a4 100644 (file)
--- a/drivers/media/usb/em28xx/em28xx-cards.c
+++ b/drivers/media/usb/em28xx/em28xx-cards.c
@@ -3566,13 +3566,12 @@ static int em28xx_init_dev(struct em28xx *dev, struct usb_device *udev,
 static int em28xx_duplicate_dev(struct em28xx *dev)
 {
        int nr;
-       struct em28xx *sec_dev = kzalloc(sizeof(*sec_dev), GFP_KERNEL);
+       struct em28xx *sec_dev = kmemdup(dev, sizeof(*sec_dev), GFP_KERNEL);
 
        if (!sec_dev) {
                dev->dev_next = NULL;
                return -ENOMEM;
        }
-       memcpy(sec_dev, dev, sizeof(*sec_dev));
        /* Check to see next free device and mark as used */
        do {
                nr = find_first_zero_bit(em28xx_devused, EM28XX_MAXBOARDS);

diff --git a/drivers/media/usb/zr364xx/zr364xx.c b/drivers/media/usb/zr364xx/zr364xx.c
index b8e89d550d2951334174501b7a14b694f4100132..637962825d7a84d7d7450373a179176ac2dca4c5 100644 (file)
--- a/drivers/media/usb/zr364xx/zr364xx.c
+++ b/drivers/media/usb/zr364xx/zr364xx.c
@@ -197,12 +197,10 @@ static int send_control_msg(struct usb_device *udev, u8 request, u16 value,
 {
        int status;
 
-       unsigned char *transfer_buffer = kmalloc(size, GFP_KERNEL);
+       unsigned char *transfer_buffer = kmemdup(cp, size, GFP_KERNEL);
        if (!transfer_buffer)
                return -ENOMEM;
 
-       memcpy(transfer_buffer, cp, size);
-
        status = usb_control_msg(udev,
                                 usb_sndctrlpipe(udev, 0),
                                 request,