On 09/11/2014 11:17 AM, Ilya Dryomov wrote: > On Thu, Sep 11, 2014 at 7:23 PM, Alex Elder <elder@xxxxxxxx> wrote: >> On 09/11/2014 10:10 AM, Ilya Dryomov wrote: >>> Trying to map an image out of a pool for which we don't have an 'x' >>> permission bit fails with -ERANGE from ceph_extract_encoded_string() >>> due to an unsigned vs signed bug. Fix it and get rid of the -ENIVAL >>> sink, thus exposing rbd::get_id cls method return value. (I've seen >>> a bunch of unexplained -ERANGE reports, I bet this is it). >>> >>> Signed-off-by: Ilya Dryomov <ilya.dryomov@xxxxxxxxxxx> >> >> I often think people are annoyed by my explicit type casts >> all over the place. This (missed) one matters a lot. >> >> I think the -EINVAL was to ensure an error code that was >> expected by a write() call would be returned. > > Yeah, the way it's written it's possible in theory to get a positive > return value from rbd_dev_image_id(). Looking deeper, this sizeof() is > not needed at all - ceph_extract_encoded_string() deals with short > buffers as it should. As for the ret == sizeof(u32) (i.e. an empty > string), neither userspace nor us check against empty strings in > similar cases (object prefix, snapshot name, etc). I should have asked this before. Why is a permission error leading to ceph_extract_encoded_string() finding a short buffer? I didn't take the time to trace the error path you're talking about here all the way back. (I'm looking at your new patch in the mean time.) -Alex -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
