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From:   Yu Kuai <yukuai3@huawei.com>
To:     <steffen.klassert@secunet.com>, <herbert@gondor.apana.org.au>,
        <davem@davemloft.net>, <kuba@kernel.org>, <0x7f454c46@gmail.com>
CC:     <netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <yukuai3@huawei.com>, <yi.zhang@huawei.com>,
        <zhangxiaoxu5@huawei.com>
Subject: [PATCH] net: xfrm: fix memory leak in xfrm_user_policy()
Date:   Tue, 10 Nov 2020 09:14:43 +0800
Message-ID: <20201110011443.2482437-1-yukuai3@huawei.com>
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Precedence: bulk

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 <hulkci@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@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