Bug report: git grep seems to use the wrong .gitattributes when invoked in a subdirectory

Greetings,

I bumped into a problem where git grep thinks files in repo/a/data are
binary files when it is invoked from repo/a and
repo/data/.gitattributes contains "* binary".

I can reproduce this on 1.7.9.5 and 1.7.10.4. Unfortunately I don't
have a newer version at hand.

How to reproduce:

[pseudo:~/tmp]% git --version
git version 1.7.10.4
[pseudo:~/tmp]% git init git-test
Initialized empty Git repository in /home/opqdonut/tmp/git-test/.git/
[pseudo:~/tmp]% cd git-test
[pseudo:~/tmp/git-test:master()]% mkdir -p a/data
[pseudo:~/tmp/git-test:master()]% mkdir data
[pseudo:~/tmp/git-test:master()]% echo '* binary' > data/.gitattributes
[pseudo:~/tmp/git-test:master()]% echo foo > a/data/foo
[pseudo:~/tmp/git-test:master()]% git add -A
[pseudo:~/tmp/git-test:master()]% git commit -m "foo"
[master (root-commit) 20fafbb] foo
 2 files changed, 1 insertion(+)
 create mode 100644 a/data/foo
 create mode 100644 data/.gitattributes
[pseudo:~/tmp/git-test:master()]% git grep foo
a/data/foo:foo
[pseudo:~/tmp/git-test:master()]% cd a
[pseudo:~/tmp/git-test/a:master()]% git grep foo
Binary file data/foo matches

(Please CC me on replies, I'm not subscribed to the list.)

--
Joel Kaasinen
joel.kaasinen@gmail.com