[PATCH] net: xfrm: fix memory leak in xfrm_user_policy()

[Yu Kuai]

if xfrm_get_translator() failed, xfrm_user_policy() return without
freeing 'data', which is allocated in memdup_sockptr().

Fixes: 96392ee5a13b ("xfrm/compat: Translate 32-bit user_policy from sockptr")
Reported-by: Hulk Robot <hul...@huawei.com>
Signed-off-by: Yu Kuai <yuku...@huawei.com>
---
 net/xfrm/xfrm_state.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index a77da7aae6fe..2f1517827995 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -2382,8 +2382,10 @@ int xfrm_user_policy(struct sock *sk, int optname, 
sockptr_t optval, int optlen)
        if (in_compat_syscall()) {
                struct xfrm_translator *xtr = xfrm_get_translator();
 
-               if (!xtr)
+               if (!xtr) {
+                       kfree(data);
                        return -EOPNOTSUPP;
+               }
 
                err = xtr->xlate_user_policy_sockptr(&data, optlen);
                xfrm_put_translator(xtr);
-- 
2.25.4