[PATCH] xfrm: use memdup_user

From: Geliang Tang
Date: Sat May 06 2017 - 11:43:27 EST


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

Signed-off-by: Geliang Tang <geliangtang@xxxxxxxxx>
---
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