Git 2.38.1 and others for CVE-2022-39253, and CVE-2022-39260

[Taylor Blau <me () ttaylorr com>]

The Git project released new versions on 2022-10-18, addressing CVEs
2022-39253, 2022-39260. We highly recommend upgrading to one of the
fixed versions below:

  v2.30.6 v2.31.5 v2.32.4 v2.33.5 v2.34.5 v2.35.5 v2.36.3 v2.37.4 v2.38.1

If you are on the unreleased development track, the same fix is
already included, so you do not have to do anything.

https://lore.kernel.org/git/xmqq4jw1uku5.fsf@gitster.g/T/#u

The relevant information from the most recent release notes
pertaining to the above two CVEs are as follows:

CVE-2022-39253:
   When relying on the `--local` clone optimization, Git dereferences
   symbolic links in the source repository before creating hardlinks
   (or copies) of the dereferenced link in the destination repository.
   This can lead to surprising behavior where arbitrary files are
   present in a repository's `$GIT_DIR` when cloning from a malicious
   repository.

   Git will no longer dereference symbolic links via the `--local`
   clone mechanism, and will instead refuse to clone repositories that
   have symbolic links present in the `$GIT_DIR/objects` directory.

   Additionally, the value of `protocol.file.allow` is changed to be
   "user" by default.

CVE-2022-39260:
   An overly-long command string given to `git shell` can result in
   overflow in `split_cmdline()`, leading to arbitrary heap writes and
   remote code execution when `git shell` is exposed and the directory
   `$HOME/git-shell-commands` exists.

   `git shell` is taught to refuse interactive commands that are
   longer than 4MiB in size. `split_cmdline()` is hardened to reject
   inputs larger than 2GiB.

Credit for finding CVE-2022-39253 goes to Cory Snider of Mirantis. The
fix was authored by Taylor Blau, with help from Johannes Schindelin.

Credit for finding CVE-2022-39260 goes to Kevin Backhouse of GitHub.
The fix was authored by Kevin Backhouse, Jeff King, and Taylor Blau.

Thanks,
Taylor