kcm: remove a useless copy_from_user()

struct kcm_clone only contains fd, and kcm_clone() only
writes this struct, so there is no need to copy it from user.

Cc: Tom Herbert <tom@herbertland.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c
index 31762f76cdb5f2a3ec322135068402be532218ed..deca20fb2ce2e5e50063e58ec2c0d9d6239d3bd4 100644 (file)
--- a/net/kcm/kcmsock.c
+++ b/net/kcm/kcmsock.c
@@ -1707,11 +1707,7 @@ static int kcm_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
                struct kcm_clone info;
                struct socket *newsock = NULL;
 
-               if (copy_from_user(&info, (void __user *)arg, sizeof(info)))
-                       return -EFAULT;
-
                err = kcm_clone(sock, &info, &newsock);
-
                if (!err) {
                        if (copy_to_user((void __user *)arg, &info,
                                         sizeof(info))) {