[PATCH] staging:wlan-ng: use memdup_user instead of kmalloc/copy_from_user

From: Ivan Safonov
Date: Sat Feb 13 2021 - 08:17:21 EST


memdup_user() is shorter and safer equivalent
of kmalloc/copy_from_user pair.

Signed-off-by: Ivan Safonov <insafonov@xxxxxxxxx>
---
drivers/staging/wlan-ng/p80211netdev.c | 28 ++++++++++++--------------
1 file changed, 13 insertions(+), 15 deletions(-)

diff --git a/drivers/staging/wlan-ng/p80211netdev.c b/drivers/staging/wlan-ng/p80211netdev.c
index a15abb2c8f54..6f9666dc0277 100644
--- a/drivers/staging/wlan-ng/p80211netdev.c
+++ b/drivers/staging/wlan-ng/p80211netdev.c
@@ -569,24 +569,22 @@ static int p80211knetdev_do_ioctl(struct net_device *dev,
goto bail;
}

- /* Allocate a buf of size req->len */
- msgbuf = kmalloc(req->len, GFP_KERNEL);
- if (msgbuf) {
- if (copy_from_user(msgbuf, (void __user *)req->data, req->len))
- result = -EFAULT;
- else
- result = p80211req_dorequest(wlandev, msgbuf);
+ msgbuf = memdup_user(req->data, req->len);
+ if (IS_ERR(msgbuf)) {
+ result = PTR_ERR(msgbuf);
+ goto bail;
+ }

- if (result == 0) {
- if (copy_to_user
- ((void __user *)req->data, msgbuf, req->len)) {
- result = -EFAULT;
- }
+ result = p80211req_dorequest(wlandev, msgbuf);
+
+ if (result == 0) {
+ if (copy_to_user
+ ((void __user *)req->data, msgbuf, req->len)) {
+ result = -EFAULT;
}
- kfree(msgbuf);
- } else {
- result = -ENOMEM;
}
+ kfree(msgbuf);
+
bail:
/* If allocate,copyfrom or copyto fails, return errno */
return result;
--
2.26.2