This is definitely a directory issue you are encountering. The temp directory looks like it is just off of the root at /tmp. You will probably not have access to this directory, you should contact your host to see if you can get access to this directory or have them adjust the permissions for you.
If you have the proper permissions for both directories involved, the tmp and the upload directory then you should not get this error message. Along with the upload folder you should check on the folder that it is contained in to ensure that there are not conflicting permissions.