Handle big endianness in NTLM (ntlmv2) authentication

commit fdf96a90 upstream.

This is RH bug 970891
Uppercasing of username during calculation of ntlmv2 hash fails
because UniStrupr function does not handle big endian wchars.

Also fix a comment in the same code to reflect its correct usage.

[To make it easier for stable (rather than require 2nd patch) fixed
this patch of Shirish's to remove endian warning generated
by sparse -- steve f.]
Reported-by: steve <sanpatr1@in.ibm.com>
Signed-off-by: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <smfrench@gmail.com>
[bwh: Backported to 3.2: adjust context, indentation]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

fs/cifs/cifs_unicode.h

@@ -323,14 +323,14 @@ UniToupper(register wchar_t uc)
 /*
  * UniStrupr:  Upper case a unicode string
  */
-static inline wchar_t *
-UniStrupr(register wchar_t *upin)
+static inline __le16 *
+UniStrupr(register __le16 *upin)
 {
-	register wchar_t *up;
+	register __le16 *up;
 
 	up = upin;
 	while (*up) {		/* For all characters */
-		*up = UniToupper(*up);
+		*up = cpu_to_le16(UniToupper(le16_to_cpu(*up)));
 		up++;
 	}
 	return upin;		/* Return input pointer */

fs/cifs/cifsencrypt.c

@@ -394,7 +394,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 	int rc = 0;
 	int len;
 	char nt_hash[CIFS_NTHASH_SIZE];
-	wchar_t *user;
+	__le16 *user;
 	wchar_t *domain;
 	wchar_t *server;
 
@@ -419,7 +419,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 		return rc;
 	}
 
-	/* convert ses->user_name to unicode and uppercase */
+	/* convert ses->user_name to unicode */
 	len = strlen(ses->user_name);
 	user = kmalloc(2 + (len * 2), GFP_KERNEL);
 	if (user == NULL) {
@@ -427,7 +427,7 @@ static int calc_ntlmv2_hash(struct cifs_ses *ses, char *ntlmv2_hash,
 		rc = -ENOMEM;
 		return rc;
 	}
-	len = cifs_strtoUCS((__le16 *)user, ses->user_name, len, nls_cp);
+	len = cifs_strtoUCS(user, ses->user_name, len, nls_cp);
 	UniStrupr(user);
 
 	rc = crypto_shash_update(&ses->server->secmech.sdeschmacmd5->shash,