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;
         }