xfrm_user_policy(): don't open-code memdup_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index fc3c5aa387543a63bf18955e60309207bf06e961..5780cdad2260cb82ae268dd1a7ad972302e0d64a 100644 (file)
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2023,13 +2023,9 @@ int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen
        if (optlen <= 0 || optlen > PAGE_SIZE)
                return -EMSGSIZE;
 
-       data = kmalloc(optlen, GFP_KERNEL);
-       if (!data)
-               return -ENOMEM;
-
-       err = -EFAULT;
-       if (copy_from_user(data, optval, optlen))
-               goto out;
+       data = memdup_user(optval, optlen);
+       if (IS_ERR(data))
+               return PTR_ERR(data);
 
        err = -EINVAL;
        rcu_read_lock();
@@ -2047,7 +2043,6 @@ int xfrm_user_policy(struct sock *sk, int optname, u8 __user *optval, int optlen
                err = 0;
        }
 
-out:
        kfree(data);
        return err;
 }