[PATCH 1/2] misc/mic/vop: Use memdup_user() rather than duplicating its implementation

SF Markus Elfring
2016-08-19T18:30:04Z

Date: Fri, 19 Aug 2016 19:48:45 +0200

Reuse existing functionality from memdup_user() instead of keeping
duplicate source code.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
---
drivers/misc/mic/vop/vop_vringh.c | 21 ++++++---------------
1 file changed, 6 insertions(+), 15 deletions(-)

diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index 88e4523..84c95fe 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -938,13 +938,9 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
dd.num_vq > MIC_MAX_VRINGS)
return -EINVAL;

- dd_config = kzalloc(mic_desc_size(&dd), GFP_KERNEL);
- if (!dd_config)
- return -ENOMEM;
- if (copy_from_user(dd_config, argp, mic_desc_size(&dd))) {
- ret = -EFAULT;
- goto free_ret;
- }
+ dd_config = memdup_user(argp, mic_desc_size(&dd));
+ if (IS_ERR(dd_config))
+ return PTR_ERR(dd_config);
/* Ensure desc has not changed between the two reads */
if (memcmp(&dd, dd_config, sizeof(dd))) {
ret = -EINVAL;
@@ -996,17 +992,12 @@ _unlock_ret:
ret = vop_vdev_inited(vdev);
if (ret)
goto __unlock_ret;
- buf = kzalloc(vdev->dd->config_len, GFP_KERNEL);
- if (!buf) {
- ret = -ENOMEM;
+ buf = memdup_user(argp, vdev->dd->config_len);
+ if (IS_ERR(buf)) {
+ ret = PTR_ERR(buf);
goto __unlock_ret;
}
- if (copy_from_user(buf, argp, vdev->dd->config_len)) {
- ret = -EFAULT;
- goto done;
- }
ret = vop_virtio_config_change(vdev, buf);
-done:
kfree(buf);
__unlock_ret:
mutex_unlock(&vdev->vdev_mutex);
--
2.9.3