Colin Walters
47610b45c2
If fetching GPG-signed commits over plain HTTP, a MitM attacker can fill up the drive of targets by simply returning an enormous stream for the commit object. Related to this, an attacker can also cause OSTree to perform large memory allocations by returning enormous GVariants in the metadata. This helps close that attack by limiting all metadata objects to 10 MiB, so the initial fetch will be truncated. But now the attack is only slightly more difficult as the attacker will have to return a correctly formed commit object, then return a large stream of < 10 MiB dirmeta/dirtree objects. https://bugzilla.gnome.org/show_bug.cgi?id=725921
OSTree is a tool for managing bootable, immutable, versioned filesystem trees. While it takes over some of the roles of tradtional "package managers" like dpkg and rpm, it is not a package system; nor is it a tool for managing full disk images. Instead, it sits between those levels, offering a blend of the advantages (and disadvantages) of both.
For more information, see: