fs: cifs: use kmemdup instead of kmalloc + memcpy

This replaces calls to kmalloc followed by memcpy with a single call to
kmemdup. This was found via make coccicheck.
Signed-off-by: Silviu-Mihai Popescu <silviupopescu1990@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Signed-off-by: Steve French <smfrench@gmail.com>

fs/cifs/cifs_spnego.c

@@ -37,12 +37,11 @@ cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
 	int ret;
 
 	ret = -ENOMEM;
-	payload = kmalloc(prep->datalen, GFP_KERNEL);
+	payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
 	if (!payload)
 		goto error;
 
 	/* attach the data */
-	memcpy(payload, prep->data, prep->datalen);
 	key->payload.data = payload;
 	ret = 0;
 

fs/cifs/cifsacl.c

@@ -63,11 +63,10 @@ cifs_idmap_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
 		key->datalen = prep->datalen;
 		return 0;
 	}
-	payload = kmalloc(prep->datalen, GFP_KERNEL);
+	payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
 	if (!payload)
 		return -ENOMEM;
 
-	memcpy(payload, prep->data, prep->datalen);
 	key->payload.data = payload;
 	key->datalen = prep->datalen;
 	return 0;

fs/cifs/cifssmb.c

@@ -3742,12 +3742,11 @@ CIFSSMBGetCIFSACL(const unsigned int xid, struct cifs_tcon *tcon, __u16 fid,
 			rc = -EINVAL;
 			*pbuflen = 0;
 		} else {
-			*acl_inf = kmalloc(*pbuflen, GFP_KERNEL);
+			*acl_inf = kmemdup(pdata, *pbuflen, GFP_KERNEL);
 			if (*acl_inf == NULL) {
 				*pbuflen = 0;
 				rc = -ENOMEM;
 			}
-			memcpy(*acl_inf, pdata, *pbuflen);
 		}
 	}
 qsec_out:

fs/cifs/sess.c

@@ -399,12 +399,12 @@ int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
 		return -EINVAL;
 	}
 	if (tilen) {
-		ses->auth_key.response = kmalloc(tilen, GFP_KERNEL);
+		ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
+						 GFP_KERNEL);
 		if (!ses->auth_key.response) {
 			cERROR(1, "Challenge target info allocation failure");
 			return -ENOMEM;
 		}
-		memcpy(ses->auth_key.response, bcc_ptr + tioffset, tilen);
 		ses->auth_key.len = tilen;
 	}
 
@@ -761,14 +761,14 @@ CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
 			goto ssetup_exit;
 		}
 
-		ses->auth_key.response = kmalloc(msg->sesskey_len, GFP_KERNEL);
+		ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
+						 GFP_KERNEL);
 		if (!ses->auth_key.response) {
 			cERROR(1, "Kerberos can't allocate (%u bytes) memory",
 					msg->sesskey_len);
 			rc = -ENOMEM;
 			goto ssetup_exit;
 		}
-		memcpy(ses->auth_key.response, msg->data, msg->sesskey_len);
 		ses->auth_key.len = msg->sesskey_len;
 
 		pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;