On Mon, Aug 7, 2017 at 11:30 AM, Shawn Pearce <spearce@xxxxxxxxxxx> wrote: > On Mon, Aug 7, 2017 at 11:27 AM, Stefan Beller <sbeller@xxxxxxxxxx> wrote: >> On Sun, Aug 6, 2017 at 6:47 PM, Shawn Pearce <spearce@xxxxxxxxxxx> wrote: >>> 6th iteration of the reftable storage format. >>> >>> You can read a rendered version of this here: >>> https://googlers.googlesource.com/sop/jgit/+/reftable/Documentation/technical/reftable.md >>> >>> The index may be organized into a multi-level index, where ... >>> which may in turn point to either index blocks (3rd level) or ref blocks (leaf level). >> >> So we allow 3 levels at most? > > No, its just an example. Large ref sets with small block size need 4 > levels. Or more. A malicious (or buggy) writer can produce indexes pointing to each other producing a circle. (Who would do that?) A reader should - instead of segfaulting due to unbounded recursion or being stuck in an infinite loop - ignore the indexes in this case and fallback to the slow non-indexed behavior, i.e. while the file format allows for unbounded levels, a reader should not.
