[PATCH] xfrm: use memdup_user

[Geliang Tang]

Use memdup_user() helper instead of open-coding to simplify the code.

Signed-off-by: Geliang Tang <geliangt...@gmail.com>
---
 net/xfrm/xfrm_state.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index fc3c5aa..5780cda 100644
--- 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;
 }
-- 
2.9.3