crypto: user - fix memory leak in crypto_report

mainline inclusion
from mainline-v5.4
commit ffdde5932042600c6807d46c1550b28b0db6a3bc
category: bugfix
bugzilla: 13690
CVE: CVE-2019-19062

-------------------------------------------------

In crypto_report, a new skb is created via nlmsg_new(). This skb should
be released if crypto_report_alg() fails.

Fixes: a38f7907 ("crypto: Add userspace configuration API")
Cc: <stable@vger.kernel.org>
Signed-off-by: NNavid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Conflicts:
  crypto/crypto_user.c
[yyl: crypto_report() is in crypto/crypto_user.c]
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Reviewed-by: NJason Yan <yanaijie@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>

crypto/crypto_user.c

@@ -288,8 +288,10 @@ static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
 drop_alg:
 	crypto_mod_put(alg);
 
-	if (err)
+	if (err) {
+		kfree_skb(skb);
 		return err;
+	}
 
 	return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
 }