crypto: testmgr - Fix potential memory leak in test_akcipher_one()

When the 'key' allocation fails, the 'req' will not be released,
which will cause memory leakage on this path. This patch adds a
'free_req' tag used to solve this problem, and two new err values
are added to reflect the real reason of the error.
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto/testmgr.c

@@ -3955,7 +3955,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 	key = kmalloc(vecs->key_len + sizeof(u32) * 2 + vecs->param_len,
 		      GFP_KERNEL);
 	if (!key)
-		goto free_xbuf;
+		goto free_req;
 	memcpy(key, vecs->key, vecs->key_len);
 	ptr = key + vecs->key_len;
 	ptr = test_pack_u32(ptr, vecs->algo);
@@ -3967,7 +3967,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 	else
 		err = crypto_akcipher_set_priv_key(tfm, key, vecs->key_len);
 	if (err)
-		goto free_req;
+		goto free_key;
 
 	/*
 	 * First run test which do not require a private key, such as
@@ -3977,7 +3977,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 	out_len_max = crypto_akcipher_maxsize(tfm);
 	outbuf_enc = kzalloc(out_len_max, GFP_KERNEL);
 	if (!outbuf_enc)
-		goto free_req;
+		goto free_key;
 
 	if (!vecs->siggen_sigver_test) {
 		m = vecs->m;
@@ -3996,6 +3996,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 		op = "verify";
 	}
 
+	err = -E2BIG;
 	if (WARN_ON(m_size > PAGE_SIZE))
 		goto free_all;
 	memcpy(xbuf[0], m, m_size);
@@ -4062,6 +4063,7 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 		c_size = req->dst_len;
 	}
 
+	err = -E2BIG;
 	op = vecs->siggen_sigver_test ? "sign" : "decrypt";
 	if (WARN_ON(c_size > PAGE_SIZE))
 		goto free_all;
@@ -4098,9 +4100,10 @@ static int test_akcipher_one(struct crypto_akcipher *tfm,
 free_all:
 	kfree(outbuf_dec);
 	kfree(outbuf_enc);
+free_key:
+	kfree(key);
 free_req:
 	akcipher_request_free(req);
-	kfree(key);
 free_xbuf:
 	testmgr_free_buf(xbuf);
 	return err;