Attempted mounting read-only after failed permission to read-write

If a partition image could not be opened read-write, retry as read-only

libntfs-3g/unix_io.c

@@ -143,6 +143,9 @@ static int ntfs_device_unix_io_open(struct ntfs_device *dev, int flags)
 	*(int*)dev->d_private = open(dev->d_name, flags);
 	if (*(int*)dev->d_private == -1) {
 		err = errno;
+			/* if permission error and rw, retry read-only */
+		if ((err == EACCES) && ((flags & O_RDWR) == O_RDWR))
+			err = EROFS;
 		goto err_out;
 	}
 #ifdef HAVE_LINUX_FS_H

libntfs-3g/volume.c

@@ -529,7 +529,7 @@ ntfs_volume *ntfs_volume_startup(struct ntfs_device *dev,
 						dev->d_name);
 				goto error_exit;
 			} else {
-				ntfs_log_info("Can only open '%s' as read-only\n",
+				ntfs_log_info("Error opening '%s' read-write\n",
 						dev->d_name);
 				NVolSetReadOnly(vol);
 			}