Pushing to repositories fails on Docker for Windows

I was fiddeling around with the new Docker for Windows beta and there were a couple of problems when trying to run the provided docker-compose.yml out of the box (the biggest problem seems to be the current incompatibility between PostgreSQL and Docker for Windows, see https://forums.docker.com/t/data-directory-var-lib-postgresql-data-pgdata-has-wrong-ownership/17963/8). It was possible to work around most of the problems, however, whenever I try to push some slightly bigger commits, I receive the following error:

Counting objects: 21, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (13/13), done.
FATAL ERROR: Server sent disconnect message
type 2 (protocol error):
"Packet corrupt"
fatal: The remote end hung up unexpectedly
fatal: sha1 file '<stdout>' write error: Broken pipe
error: failed to push some refs to 'ssh://git@localhost:10022/root/spring-boot-example.git'

Or sometimes:

Counting objects: 21, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (13/13), done.
Writing objects: 100% (21/21), 51.35 KiB | 0 bytes/s, done.
Total 21 (delta 0), reused 0 (delta 0)
FATAL ERROR: Server sent disconnect message
type 2 (protocol error):
"Packet corrupt"
fatal: The remote end hung up unexpectedly
fatal: The remote end hung up unexpectedly

And gitlab logs the following output:
gitlab_1 | 2016-07-20 23:02:50,366 CRIT reaped unknown pid 525)

I think this problem might have something to do with supervisord, but I'm not really sure. A similar problem exists when pushing via HTTP as well.

Start with the provided docker-compose.yml and the Docker for Windows setup, then reproduce a larger push over both SSH and HTTP. Inspect the supervisord behavior alongside the GitLab log entry showing the reaped process; done means repository pushes complete without protocol errors or broken pipes.