crypto: ccp - Use kmemdup in ccp_copy_and_save_keypart()

Use kmemdup rather than duplicating its implementation
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Acked-by: NGary R Hook <gary.hook@amd.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/ccp/ccp-crypto-rsa.c

@@ -37,10 +37,9 @@ static inline int ccp_copy_and_save_keypart(u8 **kpbuf, unsigned int *kplen,
 		if (buf[nskip])
 			break;
 	*kplen = sz - nskip;
-	*kpbuf = kzalloc(*kplen, GFP_KERNEL);
+	*kpbuf = kmemdup(buf + nskip, *kplen, GFP_KERNEL);
 	if (!*kpbuf)
 		return -ENOMEM;
-	memcpy(*kpbuf, buf + nskip, *kplen);
 
 	return 0;
 }