On Sun, Jan 08, 2017 at 10:31:22AM -0500, Mimi Zohar wrote: > > Depends on the file system. In addition to XFS at least the NFS > > also uses i_rwsem by default. Also all file systems supporting > > a DAX I/O path. > > We're only interested in the integrity of the local file system. And I'm only interested in supporting sane use cases that don't include IMA. But even if you only care about local file systems IMA is simply fundamentally broken. Read/Write zerialization in Linux has always been in the fs (or generic library called by it) and not by the caller. > IMA needs a mechanism for quickly reading a file to calculate the file > hash and validate (or set) the file signature/hash stored as an xattr, > prior to any other process getting access to the file. And that's simply not doable in Linux from a layer outside the file system. And really questionable even from inside the fs. We should simply drop IMA from the tree in the current state because it's obviously broken. If you can convince fs maintainers to do the right calls from the file systems itself for given file systems (and only support IMA for those) we can add it back just for those. -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
