I have a bare-git central repos + SVN-git bridge - a repos with git svn, tracking SVN in branch 'current' and tracking GIT repository in branch 'gitcentral'
Then I use post-update hook in central git repos like that:
#!/bin/bash
# Anything inserted into GIT - move it back to SVN
echo
echo '* Pushing data into SVN branch'
cd /home/git/BRIDGE
unset GIT_DIR
# current - svn branch locally and central git branch on project.git repos
# centralgit - unmodified centralgit branch
git fetch /home/git/repositories/project.git/ master:centralgit || (echo "Error while pulling data into bridge repository"; exit 1)
git checkout -b temp centralgit || exit 2
git rebase current || exit 3
git checkout current || exit 4
git reset --hard temp || exit 5
git svn dcommit || exit 6
git branch -D temp || exit 7
echo '* Pushed correctly data into SVN'
exit 0
That's mostly temporal, but works...