cifs: change CIFSSMBUnixQuerySymLink to use new helpers

Change CIFSSMBUnixQuerySymLink to use the new unicode helper functions.
Also change the calling conventions so that the allocation of the target
name buffer is done in CIFSSMBUnixQuerySymLink rather than by the caller.

Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: Suresh Jayaraman <sjayaraman@suse.de>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifssmb.c

@@ -2382,8 +2382,7 @@ winCreateHardLinkRetry:
 
 int
 CIFSSMBUnixQuerySymLink(const int xid, struct cifsTconInfo *tcon,
-			const unsigned char *searchName,
-			char *symlinkinfo, const int buflen,
+			const unsigned char *searchName, char **symlinkinfo,
 			const struct nls_table *nls_codepage)
 {
 /* SMB_QUERY_FILE_UNIX_LINK */
@@ -2393,6 +2392,7 @@ CIFSSMBUnixQuerySymLink(const int xid, struct cifsTconInfo *tcon,
 	int bytes_returned;
 	int name_len;
 	__u16 params, byte_count;
+	char *data_start;
 
 	cFYI(1, ("In QPathSymLinkInfo (Unix) for path %s", searchName));
 
@@ -2447,30 +2447,22 @@ querySymLinkRetry:
 		/* decode response */
 
 		rc = validate_t2((struct smb_t2_rsp *)pSMBr);
-		if (rc || (pSMBr->ByteCount < 2))
 		/* BB also check enough total bytes returned */
-			rc = -EIO;	/* bad smb */
+		if (rc || (pSMBr->ByteCount < 2))
+			rc = -EIO;
 		else {
-			__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
-			__u16 count = le16_to_cpu(pSMBr->t2.DataCount);
+			u16 count = le16_to_cpu(pSMBr->t2.DataCount);
+
+			data_start = ((char *) &pSMBr->hdr.Protocol) +
+					   le16_to_cpu(pSMBr->t2.DataOffset);
 
-			if (pSMBr->hdr.Flags2 & SMBFLG2_UNICODE) {
-				name_len = UniStrnlen((wchar_t *) ((char *)
-					&pSMBr->hdr.Protocol + data_offset),
-					min_t(const int, buflen, count) / 2);
 			/* BB FIXME investigate remapping reserved chars here */
-				cifs_strfromUCS_le(symlinkinfo,
-					(__le16 *) ((char *)&pSMBr->hdr.Protocol
-							+ data_offset),
-					name_len, nls_codepage);
-			} else {
-				strncpy(symlinkinfo,
-					(char *) &pSMBr->hdr.Protocol +
-						data_offset,
-					min_t(const int, buflen, count));
-			}
-			symlinkinfo[buflen] = 0;
-	/* just in case so calling code does not go off the end of buffer */
+			*symlinkinfo = cifs_strndup(data_start, count,
+						    pSMBr->hdr.Flags2 &
+							SMBFLG2_UNICODE,
+						    nls_codepage);
+			if (!symlinkinfo)
+				rc = -ENOMEM;
 		}
 	}
 	cifs_buf_release(pSMB);