[PATCH] misc: mic: Use memdup_user() as a cleanup

From: Vasyl Gomonovych
Date: Wed Nov 22 2017 - 10:25:46 EST


Fix coccicheck warning which recommends to use memdup_user():

drivers/misc/mic/vop/vop_vringh.c:940:14-21: WARNING opportunity for memdup_user
drivers/misc/mic/vop/vop_vringh.c:998:8-15: WARNING opportunity for memdup_user

Generated by: scripts/coccinelle/memdup_user/memdup_user.cocci

Signed-off-by: Vasyl Gomonovych <gomonovych@xxxxxxxxx>
---
drivers/misc/mic/vop/vop_vringh.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/misc/mic/vop/vop_vringh.c b/drivers/misc/mic/vop/vop_vringh.c
index fed992e2c258..bde0305ebd91 100644
--- a/drivers/misc/mic/vop/vop_vringh.c
+++ b/drivers/misc/mic/vop/vop_vringh.c
@@ -937,13 +937,10 @@ 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;
@@ -995,15 +992,11 @@ static long vop_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
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);
--
1.9.1