Re: [PATCH 0/9] reducing memory allocations for v2 servers

On Wed, Sep 15, 2021 at 02:25:49AM +0200, Ævar Arnfjörð Bjarmason wrote:

On Tue, Sep 14 2021, Jeff King wrote:

quoted

While looking at [1], I noticed that v2 servers will read a few bits of
client input into strvecs. Even though we expect these to be small-ish,
there's nothing preventing a client from sending us a bunch of junk and
wasting memory.

[...]

quoted

[1] https://lore.kernel.org/git/YT54CNYgtGcqexwq@coredump.intra.peff.net/ (local)

When I first read this I expected it to be a link to
https://lore.kernel.org/git/YPCsDLoiiAG%2FC%2Fft@coredump.intra.peff.net/ (local);
i.e. that the object-info leak discussion back in July had encouraged
you to work on this ... :)

Nope, I got terrified by the "yes | upload-pack" example I showed
earlier. :)

I was really worried it could turn into a heap overflow, but it turns
out that it cannot. But I still think tightening things up (and avoiding
any memory-consumption attacks) is worth doing.

-Peff