CIFS: refactor crypto shash/sdesc allocation&free

shash and sdesc and always allocated and freed together.
* abstract this in new functions cifs_alloc_hash() and cifs_free_hash().
* make smb2/3 crypto allocation independent from each other.

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
CC: Stable <stable@vger.kernel.org>

1 files changed, 7 insertions, 71 deletions

diff --git a/fs/cifs/cifsencrypt.c b/fs/cifs/cifsencrypt.c
index f2b0a7f124da..478a145aa4d0 100644
--- a/fs/cifs/cifsencrypt.c
+++ b/fs/cifs/cifsencrypt.c
@@ -36,37 +36,6 @@
 #include <crypto/skcipher.h>
 #include <crypto/aead.h>
 
-static int
-cifs_crypto_shash_md5_allocate(struct TCP_Server_Info *server)
-{
-	int rc;
-	unsigned int size;
-
-	if (server->secmech.sdescmd5 != NULL)
-		return 0; /* already allocated */
-
-	server->secmech.md5 = crypto_alloc_shash("md5", 0, 0);
-	if (IS_ERR(server->secmech.md5)) {
-		cifs_dbg(VFS, "could not allocate crypto md5\n");
-		rc = PTR_ERR(server->secmech.md5);
-		server->secmech.md5 = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.md5);
-	server->secmech.sdescmd5 = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdescmd5) {
-		crypto_free_shash(server->secmech.md5);
-		server->secmech.md5 = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdescmd5->shash.tfm = server->secmech.md5;
-	server->secmech.sdescmd5->shash.flags = 0x0;
-
-	return 0;
-}
-
 int __cifs_calc_signature(struct smb_rqst *rqst,
 			struct TCP_Server_Info *server, char *signature,
 			struct shash_desc *shash)
@@ -132,13 +101,10 @@ static int cifs_calc_signature(struct smb_rqst *rqst,
 	if (!rqst->rq_iov || !signature || !server)
 		return -EINVAL;
 
-	if (!server->secmech.sdescmd5) {
-		rc = cifs_crypto_shash_md5_allocate(server);
-		if (rc) {
-			cifs_dbg(VFS, "%s: Can't alloc md5 crypto\n", __func__);
-			return -1;
-		}
-	}
+	rc = cifs_alloc_hash("md5", &server->secmech.md5,
+			     &server->secmech.sdescmd5);
+	if (rc)
+		return -1;
 
 	rc = crypto_shash_init(&server->secmech.sdescmd5->shash);
 	if (rc) {
@@ -663,37 +629,6 @@ CalcNTLMv2_response(const struct cifs_ses *ses, char *ntlmv2_hash)
 	return rc;
 }
 
-static int crypto_hmacmd5_alloc(struct TCP_Server_Info *server)
-{
-	int rc;
-	unsigned int size;
-
-	/* check if already allocated */
-	if (server->secmech.sdeschmacmd5)
-		return 0;
-
-	server->secmech.hmacmd5 = crypto_alloc_shash("hmac(md5)", 0, 0);
-	if (IS_ERR(server->secmech.hmacmd5)) {
-		cifs_dbg(VFS, "could not allocate crypto hmacmd5\n");
-		rc = PTR_ERR(server->secmech.hmacmd5);
-		server->secmech.hmacmd5 = NULL;
-		return rc;
-	}
-
-	size = sizeof(struct shash_desc) +
-			crypto_shash_descsize(server->secmech.hmacmd5);
-	server->secmech.sdeschmacmd5 = kmalloc(size, GFP_KERNEL);
-	if (!server->secmech.sdeschmacmd5) {
-		crypto_free_shash(server->secmech.hmacmd5);
-		server->secmech.hmacmd5 = NULL;
-		return -ENOMEM;
-	}
-	server->secmech.sdeschmacmd5->shash.tfm = server->secmech.hmacmd5;
-	server->secmech.sdeschmacmd5->shash.flags = 0x0;
-
-	return 0;
-}
-
 int
 setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 {
@@ -757,9 +692,10 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 
 	mutex_lock(&ses->server->srv_mutex);
 
-	rc = crypto_hmacmd5_alloc(ses->server);
+	rc = cifs_alloc_hash("hmac(md5)",
+			     &ses->server->secmech.hmacmd5,
+			     &ses->server->secmech.sdeschmacmd5);
 	if (rc) {
-		cifs_dbg(VFS, "could not crypto alloc hmacmd5 rc %d\n", rc);
 		goto unlock;
 	}