workflows/release-binaries: Remove .git/config file from artifacts

[tstellar]

The .git/config file contains an auth token that can be leaked if the .git directory is included in a workflow artifact.

[llvmbot]

@llvm/pr-subscribers-github-workflow

Author: Tom Stellard (tstellar)

Changes

The .git/config file contains an auth token that can be leaked if the .git directory is included in a workflow artifact.

---

Full diff: https://github.com/llvm/llvm-project/pull/106310.diff

1 Files Affected:

• (modified) .github/workflows/release-binaries-save-stage/action.yml (+4)

diff --git a/.github/workflows/release-binaries-save-stage/action.yml b/.github/workflows/release-binaries-save-stage/action.yml
index e2f3eeadd15bea..63d00255f6d8fb 100644
--- a/.github/workflows/release-binaries-save-stage/action.yml
+++ b/.github/workflows/release-binaries-save-stage/action.yml
@@ -18,6 +18,10 @@ runs:
     - name: Package Build and Source Directories
       shell: bash
       run: |
+        # Remove git directory so we avoid leaking secrets stored in .git/config.
+        # See https://unit42.paloaltonetworks.com/github-repo-artifacts-leak-tokens/
+        # This also helps reduce the size of the archive.
+        rm -Rf .git/
         # Windows does not support symlinks, so we need to dereference them.
         tar --exclude build/ ${{ (runner.os == 'Windows' && '-h') || '' }} -c . | zstd -T0 -c > ../llvm-project.tar.zst
         mv ../llvm-project.tar.zst .

[boomanaiden154]

Did you come across this from the article or was there some scanner involved here?

I'm assuming the token by default won't have a large amount of permissions though and should be ephemeral?

Speaking of that, do we want to tack on a

permissions:
  contents: read

at the top?

[tstellar]

Did you come across this from the article or was there some scanner involved here?

It's from the article linked in the comment.

I'm assuming the token by default won't have a large amount of permissions though and should be ephemeral?

The called workflow inherits the caller permissions, so the tokens should be read-only and only usable while the workflow is running.

Speaking of that, do we want to tack on a

permissions:
  contents: read

I'm not sure if the composite actions support top-level permissions, but I'll try it.

[boomanaiden154]

I'm not sure if the composite actions support top-level permissions, but I'll try it.

Ah, it's an action. I did not realize that.

[tru]

LGTM

[tstellar]

/cherry-pick ef50970

[llvmbot]

/pull-request #106821