crypto: hisilicon/hpre - fix memory leak in hpre_curve25519_src_init()

mainline inclusion
from mainline-v5.17-rc1
commit 51fa916b
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5AFY1
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=51fa916b81e5

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

hpre_curve25519_src_init() allocates memory for 'ptr' before calling
memcmp(). If memcmp() returns 0, the function will return '-EINVAL'
without freeing memory.
Signed-off-by: NWeili Qian <qianweili@huawei.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NJiangshui Yang <yangjiangshui@h-partners.com>
Reviewed-by: NYang Shen <shenyang39@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/crypto/hisilicon/hpre/hpre_crypto.c

@@ -1862,7 +1862,7 @@ static int hpre_curve25519_src_init(struct hpre_asym_request *hpre_req,
 	 */
 	if (memcmp(ptr, p, ctx->key_sz) == 0) {
 		dev_err(dev, "gx is p!\n");
-		return -EINVAL;
+		goto err;
 	} else if (memcmp(ptr, p, ctx->key_sz) > 0) {
 		hpre_curve25519_src_modulo_p(ptr);
 	}