Merge 38d7929545 into 421290d066

agent/dashboard/workflow_approval.py

@@ -44,6 +44,33 @@ async def workflow_push_approved(thread_id: str, fingerprint: str) -> bool:
     return approvals.get(fingerprint, {}).get("status") == WORKFLOW_APPROVAL_APPROVED
 
 
+async def workflow_push_rejected(thread_id: str, fingerprint: str) -> bool:
+    approvals = await get_workflow_push_approvals(thread_id)
+    return approvals.get(fingerprint, {}).get("status") == WORKFLOW_APPROVAL_REJECTED
+
+
+async def find_workflow_push_approval(
+    thread_id: str,
+    *,
+    repo: str,
+    branch: str,
+    files: list[str],
+) -> dict[str, Any] | None:
+    """Return the most recent approved record matching identity-level keys, if any."""
+    approvals = await get_workflow_push_approvals(thread_id)
+    identity = (repo, branch, tuple(sorted(files)))
+    matches = [
+        r
+        for r in approvals.values()
+        if r.get("status") == WORKFLOW_APPROVAL_APPROVED
+        and (r.get("repo"), r.get("branch"), tuple(sorted(r.get("files", [])))) == identity
+    ]
+    if not matches:
+        return None
+    matches.sort(key=lambda r: str(r.get("decided_at", "")), reverse=True)
+    return matches[0]
+
+
 async def ensure_workflow_push_pending(
     thread_id: str,
     *,

agent/middleware/workflow_push_guard.py

@@ -22,8 +22,10 @@ from langgraph.types import Command
 
 from ..dashboard.workflow_approval import (
     ensure_workflow_push_pending,
+    find_workflow_push_approval,
     mark_workflow_push_notified,
     workflow_push_approved,
+    workflow_push_rejected,
 )
 from ..tools.slack_thread_reply import build_workflow_approval_blocks
 from ..utils.github_app import (
@@ -44,6 +46,15 @@ _GIT_OBJECT_ID = re.compile(r"^[0-9a-fA-F]{40,64}$")
 _UNSAFE_RAW_COMMAND = re.compile(r"[;|`$<>\n\r]")
 
 
+class _BlockedGitPush:
+    """Sentinel returned by the parser when a git push command is unsafe or unrecognized."""
+
+    __slots__ = ("reason",)
+
+    def __init__(self, reason: str) -> None:
+        self.reason = reason
+
+
 @dataclass(frozen=True)
 class ParsedGitPush:
     repo_dir: str | None
@@ -58,13 +69,15 @@ class WorkflowPushChange:
     fingerprint: str
     repo: str
     branch: str
-    base_sha: str
-    head_sha: str
     files: list[str]
+    head_sha: str
     remote: str
     local_ref: str
     remote_ref: str
     fixed_command: str
+    base_sha: str = ""
+    blocked: bool = False
+    blocked_reason: str = ""
 
 
 @dataclass(frozen=True)
@@ -143,28 +156,30 @@ def _response_ok(response: Any) -> bool:
     return True
 
 
-def _parse_git_push(command: str) -> ParsedGitPush | None:
+def _parse_git_push(command: str) -> ParsedGitPush | _BlockedGitPush | None:
     stripped = command.strip()
     if _UNSAFE_RAW_COMMAND.search(stripped) or "&" in stripped.replace("&&", ""):
-        return None
+        return _BlockedGitPush("unsafe shell characters in git push command")
     try:
         tokens = shlex.split(stripped)
     except ValueError:
-        return None
+        return _BlockedGitPush("unparseable git push command")
     if not tokens:
         return None
 
     if len(tokens) >= 4 and tokens[0] == "cd" and tokens[2] == "&&":
         if any(token in _SHELL_OPERATORS or token == "&&" for token in tokens[3:]):
-            return None
+            return _BlockedGitPush("chained shell commands in git push")
         return _parse_git_tokens(tokens[3:], repo_dir=tokens[1])
 
     if any(token in _SHELL_OPERATORS or token == "&&" for token in tokens):
-        return None
+        return _BlockedGitPush("chained shell commands")
     return _parse_git_tokens(tokens, repo_dir=None)
 
 
-def _parse_git_tokens(tokens: list[str], *, repo_dir: str | None) -> ParsedGitPush | None:
+def _parse_git_tokens(
+    tokens: list[str], *, repo_dir: str | None
+) -> ParsedGitPush | _BlockedGitPush | None:
     if not tokens or tokens[0] != "git":
         return None
     i = 1
@@ -173,22 +188,25 @@ def _parse_git_tokens(tokens: list[str], *, repo_dir: str | None) -> ParsedGitPu
             repo_dir = tokens[i + 1]
             i += 2
             continue
+        # Any non-push git command (e.g. git status) is not a push, so let it pass.
         return None
     if i >= len(tokens) or tokens[i] != "push":
         return None
     return _parse_push_args(tokens[i + 1 :], repo_dir=repo_dir)
 
 
-def _parse_push_args(tokens: list[str], *, repo_dir: str | None) -> ParsedGitPush | None:
+def _parse_push_args(
+    tokens: list[str], *, repo_dir: str | None
+) -> ParsedGitPush | _BlockedGitPush | None:
     set_upstream = False
     while tokens and tokens[0] in {"-u", "--set-upstream"}:
         set_upstream = True
         tokens = tokens[1:]
     if len(tokens) != 2 or tokens[0] != "origin":
-        return None
+        return _BlockedGitPush("unrecognized or unsafe git push arguments")
     parsed = _parse_refspec(tokens[1])
     if parsed is None:
-        return None
+        return _BlockedGitPush("unrecognized or unsafe git push refspec")
     local_ref, remote_ref = parsed
     return ParsedGitPush(
         repo_dir=repo_dir,
@@ -282,6 +300,66 @@ def _run_coroutine_sync(coro: Awaitable[ToolMessage | Command]) -> ToolMessage |
     return value
 
 
+def _parse_ls_tree(output: str) -> list[tuple[str, str]]:
+    """Parse `git ls-tree -r` output into a sorted list of (sha, path) tuples."""
+    entries: list[tuple[str, str]] = []
+    for line in output.splitlines():
+        line = line.strip()
+        if not line:
+            continue
+        # Format: "<mode> <type> <sha>\t<path>"
+        meta, _, path = line.partition("\t")
+        if not path:
+            continue
+        parts = meta.split()
+        if len(parts) < 3:
+            continue
+        entries.append((parts[2], path))
+    entries.sort(key=lambda item: item[1])
+    return entries
+
+
+def _workflow_tree_at_ref(
+    backend: Any, repo_dir: str | None, ref: str
+) -> tuple[list[tuple[str, str]], str] | None:
+    """Return the sorted workflow tree entries and a stable hash for the given ref.
+
+    Returns an empty list when the ref has no workflow files, so callers can detect
+    additions and deletions against a base ref.
+    """
+    ls_tree = _run_git(backend, repo_dir, f"ls-tree -r {shlex.quote(ref)} -- .github/workflows")
+    if not ls_tree.ok:
+        return None
+    entries = _parse_ls_tree(ls_tree.output)
+    content_hash = _fingerprint({"tree": entries})
+    return entries, content_hash
+
+
+def _fetch_remote_base(backend: Any, repo_dir: str | None, remote: str, branch: str) -> str | None:
+    """Fetch the base ref from the authenticated remote and return a local alias for it.
+
+    Fetches the pushed branch first; if it does not exist on the remote, fetches the
+    remote's default branch. Uses `FETCH_HEAD` so the base is bound to the freshly-fetched
+    remote tip, not a local `refs/remotes/origin/*` ref that the sandbox could rewrite.
+    """
+    fetch = _run_git(backend, repo_dir, f"fetch {shlex.quote(remote)} {shlex.quote(branch)}")
+    if fetch.ok:
+        return "FETCH_HEAD"
+
+    default = _run_git(backend, repo_dir, "ls-remote --symref origin HEAD")
+    default_branch = ""
+    if default.ok:
+        default_branch = _first_line(default.output).removeprefix("ref: refs/heads/").split("\t")[0]
+
+    for fallback in (default_branch, "dev", "main"):
+        if not fallback or fallback == branch:
+            continue
+        fetch = _run_git(backend, repo_dir, f"fetch {shlex.quote(remote)} {shlex.quote(fallback)}")
+        if fetch.ok:
+            return "FETCH_HEAD"
+    return None
+
+
 def _workflow_change_for_push(backend: Any, parsed: ParsedGitPush) -> WorkflowPushChange | None:
     root_result = _run_git(backend, parsed.repo_dir, "rev-parse --show-toplevel")
     if not root_result.ok:
@@ -302,42 +380,19 @@ def _workflow_change_for_push(backend: Any, parsed: ParsedGitPush) -> WorkflowPu
     if not head or not _GIT_OBJECT_ID.fullmatch(head):
         return None
 
-    remote_branch = f"refs/remotes/{parsed.remote}/{parsed.remote_ref}"
-    remote_branch_exists = _run_git(
-        backend, root, f"rev-parse --verify {shlex.quote(remote_branch)}"
-    )
-    if remote_branch_exists.ok and _first_line(remote_branch_exists.output):
-        base_ref = remote_branch
-        range_expr = f"{shlex.quote(base_ref)}..{shlex.quote(head)}"
-        base_sha = _first_line(_run_git(backend, root, f"rev-parse {shlex.quote(base_ref)}").output)
-    else:
-        origin_head = _run_git(backend, root, "symbolic-ref --short refs/remotes/origin/HEAD")
-        base_ref = _first_line(origin_head.output) if origin_head.ok else "origin/main"
-        range_expr = f"{shlex.quote(base_ref)}...{shlex.quote(head)}"
-        base_sha = _first_line(
-            _run_git(
-                backend, root, f"merge-base {shlex.quote(head)} {shlex.quote(base_ref)}"
-            ).output
-        )
-
-    names = _run_git(
-        backend,
-        root,
-        f"diff --name-only --diff-filter=ACMRTD {range_expr} -- .github/workflows",
-    )
-    if not names.ok:
-        return None
-    files = sorted(
-        line.strip()
-        for line in names.output.splitlines()
-        if line.strip().startswith(_WORKFLOW_PREFIX)
-    )
-    if not files:
+    head_tree = _workflow_tree_at_ref(backend, root, head)
+    if head_tree is None:
         return None
 
-    diff = _run_git(backend, root, f"diff --binary --full-index {range_expr} -- .github/workflows")
-    if not diff.ok or not diff.output:
-        return None
+    base_ref = _fetch_remote_base(backend, root, parsed.remote, branch_name)
+    if base_ref is not None:
+        base_tree = _workflow_tree_at_ref(backend, root, base_ref)
+        if base_tree is not None and head_tree[0] == base_tree[0]:
+            # No workflow change against the trusted remote base.
+            return None
+
+    head_entries, head_content_hash = head_tree
+    files = sorted({path for _sha, path in head_entries})
 
     remote = _run_git(backend, root, "config --get remote.origin.url")
     repo = _normalize_remote(_first_line(remote.output)) if remote.ok else ""
@@ -347,25 +402,18 @@ def _workflow_change_for_push(backend: Any, parsed: ParsedGitPush) -> WorkflowPu
         fixed_args.append("--set-upstream")
     fixed_args.extend([parsed.remote, fixed_refspec])
     fixed_command = _git_command(root, " ".join(shlex.quote(arg) for arg in fixed_args))
-    payload = {
+    content_payload = {
         "repo": repo,
         "branch": branch_name,
-        "base_sha": base_sha,
-        "head_sha": head,
         "files": files,
-        "diff": diff.output,
-        "remote": parsed.remote,
-        "local_ref": parsed.local_ref,
-        "remote_ref": parsed.remote_ref,
-        "fixed_refspec": fixed_refspec,
+        "content_hash": head_content_hash,
     }
     return WorkflowPushChange(
-        fingerprint=_fingerprint(payload),
+        fingerprint=_fingerprint(content_payload),
         repo=repo,
         branch=branch_name,
-        base_sha=base_sha,
-        head_sha=head,
         files=files,
+        head_sha=head,
         remote=parsed.remote,
         local_ref=parsed.local_ref,
         remote_ref=parsed.remote_ref,
@@ -373,17 +421,38 @@ def _workflow_change_for_push(backend: Any, parsed: ParsedGitPush) -> WorkflowPu
     )
 
 
-def _blocked_message(change: WorkflowPushChange, *, already_rejected: bool = False) -> ToolMessage:
+def _blocked_message(
+    change: WorkflowPushChange,
+    *,
+    already_rejected: bool = False,
+    stale: bool = False,
+    blocked: bool = False,
+) -> ToolMessage:
     status = "rejected" if already_rejected else "approval_required"
-    content = {
-        "status": "error",
-        "error_type": "WorkflowPushApprovalRequired",
-        "error": (
+    if blocked:
+        error = change.blocked_reason or "This git push command is not recognized as safe."
+        error_type = "WorkflowPushBlocked"
+    elif stale:
+        error = (
+            "This git push includes GitHub workflow file changes. A previous approval "
+            "exists for the same branch and workflow files, but the workflow content "
+            "at the pushed head has changed since that approval (for example, a rebase "
+            "that changed the workflow files or an amend that edited them). The thread "
+            "owner must re-approve the new fingerprint before Open SWE can push it."
+        )
+        error_type = "WorkflowPushApprovalRequired"
+    else:
+        error = (
             "This git push includes GitHub workflow file changes and requires human "
             "approval before Open SWE can push it. Retry the same standalone git push "
-            "after the thread owner approves the workflow diff."
-        ),
-        "workflow_approval_status": status,
+            "after the thread owner approves the workflow files."
+        )
+        error_type = "WorkflowPushApprovalRequired"
+    content = {
+        "status": "error",
+        "error_type": error_type,
+        "error": error,
+        "workflow_approval_status": status if not blocked else "blocked",
         "fingerprint": change.fingerprint,
         "files": change.files,
         "repo": change.repo,
@@ -414,10 +483,12 @@ def _approval_slack_message(change: WorkflowPushChange) -> str:
     branch = change.branch or "the current branch"
     return (
         "*Workflow file approval required*\n"
-        f"Open SWE is trying to push changes to GitHub workflow files in `{repo}` on `{branch}`.\n\n"
-        f"*Files:*\n{files}\n\n"
+        f"Open SWE is trying to push the workflow files below to `{repo}` on `{branch}`.\n\n"
+        f"*Files at the pushed head:*\n{files}\n\n"
         f"*Fingerprint:* `{change.fingerprint}`\n\n"
-        "Approve only if this exact workflow diff is expected. If the workflow files change, "
+        "Approval covers the exact workflow files and content listed above at the pushed head, "
+        "including future rebases or amends that replay the same workflow tree. If the set of "
+        "workflow files, the branch, or the workflow-file content at the pushed head changes, "
         "a new fingerprint will be required."
     )
 
@@ -455,6 +526,23 @@ async def _approval_state(request: ToolCallRequest, change: WorkflowPushChange)
     try:
         if await workflow_push_approved(thread_id, change.fingerprint):
             return "approved"
+        if await workflow_push_rejected(thread_id, change.fingerprint):
+            return "rejected"
+
+        # If the exact identity fingerprint is not approved, check whether a prior
+        # approval covers the same (repo, branch, files) identity. If so, the workflow
+        # tree at the pushed head changed underneath the prior approval (rebase/amend
+        # that edited workflow files), so we surface a loud re-approval message rather
+        # than a fresh silent pending record.
+        prior = await find_workflow_push_approval(
+            thread_id,
+            repo=change.repo,
+            branch=change.branch,
+            files=change.files,
+        )
+        if prior is not None:
+            return "stale_approval"
+
         record, _created = await ensure_workflow_push_pending(
             thread_id,
             fingerprint=change.fingerprint,
@@ -527,6 +615,20 @@ class WorkflowPushGuardMiddleware(AgentMiddleware):
         parsed = _parse_git_push(command)
         if parsed is None:
             return None
+        if isinstance(parsed, _BlockedGitPush):
+            return WorkflowPushChange(
+                fingerprint="",
+                repo="",
+                branch="",
+                files=[],
+                head_sha="",
+                remote="origin",
+                local_ref="",
+                remote_ref="",
+                fixed_command="",
+                blocked=True,
+                blocked_reason=parsed.reason,
+            )
         backend = _backend(_thread_id(request))
         if backend is None:
             return None
@@ -538,13 +640,31 @@ class WorkflowPushGuardMiddleware(AgentMiddleware):
         handler: Callable[[ToolCallRequest], Awaitable[ToolMessage | Command]],
         change: WorkflowPushChange,
     ) -> ToolMessage | Command:
+        if change.blocked:
+            return _tool_message_for_request(_blocked_message(change, blocked=True), request)
         thread_id = _thread_id(request)
         state = await _approval_state(request, change)
         if state == "approved" and thread_id:
             safe_request = _override_execute_command(request, change.fixed_command)
             return await _run_with_workflow_token(thread_id, request, lambda: handler(safe_request))
+        if state == "stale_approval":
+            record, _created = await ensure_workflow_push_pending(
+                thread_id,
+                fingerprint=change.fingerprint,
+                repo=change.repo,
+                branch=change.branch,
+                base_sha=change.base_sha,
+                head_sha=change.head_sha,
+                files=change.files,
+            )
+            await _post_slack_approval_if_needed(request, change, record)
         return _tool_message_for_request(
-            _blocked_message(change, already_rejected=state == "rejected"), request
+            _blocked_message(
+                change,
+                already_rejected=state == "rejected",
+                stale=state == "stale_approval",
+            ),
+            request,
         )
 
     def wrap_tool_call(

agent/prompt.py

@@ -317,7 +317,7 @@ Steps, in order:
 
 **IMPORTANT: If `git push` or `gh` returns "403", "Permission denied", or another permanent authorization failure, do not retry. Report the error to the user immediately and stop.**
 
-**IMPORTANT: Workflow files (`.github/workflows/`) may be changed only when explicitly requested. Any push that includes workflow-file changes requires human approval of the exact workflow diff fingerprint before it can proceed — do not attempt to bypass it.**
+**IMPORTANT: Workflow files (`.github/workflows/`) may be changed only when explicitly requested. Any push that includes workflow files at the pushed head requires human approval before it can proceed. Approval is keyed to the repo, branch, and the exact workflow files and content present at the pushed head, so rebases or amends that replay the same workflow tree do not require a fresh approval; changing the branch, the set of workflow files, or the workflow-file content at the pushed head does require a new approval. Do not attempt to bypass it.**
 
 4. **Notify the source** immediately after pushing and, when applicable, PR creation/update succeeds. Include a brief summary plus the PR link or branch URL:
    - Linear-triggered: use `linear_comment` with an `@mention` of the user who triggered the task

tests/test_workflow_push_guard.py

@@ -20,25 +20,66 @@ class _Response:
 class _Backend:
     id = "sandbox-id"
 
-    def __init__(self, *, workflow_files: str = ".github/workflows/ci.yml") -> None:
+    def __init__(
+        self,
+        *,
+        workflow_files: str = ".github/workflows/ci.yml",
+        tree_entries: dict[str, str] | None = None,
+        base_tree_entries: dict[str, str] | None = None,
+        remote_branches: set[str] | None = None,
+        default_branch: str = "main",
+    ) -> None:
         self.workflow_files = workflow_files
+        self.tree_entries = tree_entries
+        # Default base tree is empty so any head workflow file is treated as a change.
+        self.base_tree_entries = base_tree_entries if base_tree_entries is not None else {}
+        self.remote_branches = remote_branches or {"feature"}
+        self.default_branch = default_branch
         self.commands: list[str] = []
         self.head = "a" * 40
+        self.base_sha = "b" * 40
+
+    def _head_tree(self) -> str:
+        if self.tree_entries is not None:
+            return "".join(
+                f"100644 blob {sha}\t{path}\n" for path, sha in sorted(self.tree_entries.items())
+            )
+        files = [path for path in self.workflow_files.split("\n") if path.strip()]
+        return "".join(f"100644 blob {self.head}\t{path}\n" for path in files)
+
+    def _base_tree(self) -> str:
+        if self.base_tree_entries is not None:
+            return "".join(
+                f"100644 blob {sha}\t{path}\n"
+                for path, sha in sorted(self.base_tree_entries.items())
+            )
+        return self._head_tree()
+
+    def _fetch_branch(self, command: str) -> _Response:
+        # Format: "git -C /repo fetch origin <branch>" or "git fetch origin <branch>"
+        prefix = "fetch origin "
+        idx = command.find(prefix)
+        if idx == -1:
+            return _Response("", 1)
+        branch = command[idx + len(prefix) :].strip()
+        if branch in self.remote_branches:
+            return _Response("")
+        return _Response("", 1)
 
     def execute(self, command: str, *, timeout: int | None = None) -> _Response:
         self.commands.append(command)
         if "rev-parse --show-toplevel" in command:
             return _Response("/repo\n")
-        if "rev-parse --verify refs/remotes/origin/feature" in command:
-            return _Response("", 1)
-        if "symbolic-ref --short refs/remotes/origin/HEAD" in command:
-            return _Response("origin/main\n")
-        if f"merge-base {self.head} origin/main" in command:
-            return _Response("base-sha\n")
-        if "diff --name-only" in command:
-            return _Response(f"{self.workflow_files}\n" if self.workflow_files else "")
-        if "diff --binary --full-index" in command:
-            return _Response("diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml\n")
+        if "ls-tree -r" in command:
+            if "FETCH_HEAD" in command:
+                return _Response(self._base_tree())
+            return _Response(self._head_tree())
+        if "fetch origin" in command:
+            return self._fetch_branch(command)
+        if "ls-remote --symref origin HEAD" in command:
+            return _Response(
+                f"ref: refs/heads/{self.default_branch}\tHEAD\n{self.base_sha}\tHEAD\n"
+            )
         if "config --get remote.origin.url" in command:
             return _Response("git@github.com:langchain-ai/open-swe.git\n")
         if "rev-parse --abbrev-ref HEAD" in command:
@@ -93,11 +134,25 @@ def test_parse_git_push_supports_git_c_and_cd() -> None:
         remote_ref="feature",
         set_upstream=True,
     )
-    assert guard._parse_git_push("git status && git push") is None
-    assert guard._parse_git_push("git push origin feature; git push origin evil:feature") is None
 
 
-def test_workflow_change_for_push_fingerprints_workflow_diff() -> None:
+def test_parse_git_push_blocks_unsafe_and_unrecognized_forms() -> None:
+    assert isinstance(guard._parse_git_push("git status && git push"), guard._BlockedGitPush)
+    assert isinstance(
+        guard._parse_git_push("git push origin feature; git push origin evil:feature"),
+        guard._BlockedGitPush,
+    )
+    assert isinstance(
+        guard._parse_git_push("git push --force origin feature"), guard._BlockedGitPush
+    )
+    assert isinstance(guard._parse_git_push("git push origin"), guard._BlockedGitPush)
+    assert isinstance(
+        guard._parse_git_push("git push origin HEAD~1:feature"), guard._BlockedGitPush
+    )
+    assert guard._parse_git_push("git status") is None
+
+
+def test_workflow_change_for_push_fingerprints_head_workflow_tree() -> None:
     backend = _Backend()
     change = guard._workflow_change_for_push(
         backend,
@@ -154,6 +209,12 @@ async def test_unapproved_workflow_push_blocks_and_posts_slack(
     async def fake_approved(thread_id: str, fingerprint: str) -> bool:
         return False
 
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
     async def fake_pending(thread_id: str, **kwargs: Any) -> tuple[dict[str, Any], bool]:
         return {"fingerprint": kwargs["fingerprint"], "status": "pending", "notified": False}, True
 
@@ -169,6 +230,8 @@ async def test_unapproved_workflow_push_blocks_and_posts_slack(
         posted["notified"] = fingerprint
 
     monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
     monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
     monkeypatch.setattr(guard, "post_slack_thread_reply_with_ts", fake_post)
     monkeypatch.setattr(guard, "mark_workflow_push_notified", fake_notified)
@@ -205,7 +268,11 @@ async def test_approved_workflow_push_elevates_and_restores(
         refreshed.append(dict(permissions))
         return True
 
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
     monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
     monkeypatch.setattr(guard, "refresh_proxy_token", fake_refresh)
 
     pushed_command = ""
@@ -241,7 +308,11 @@ async def test_workflow_push_restoration_falls_back_when_actions_read_unavailabl
         refreshed.append(dict(permissions))
         return "actions" not in permissions
 
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
     monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
     monkeypatch.setattr(guard, "refresh_proxy_token", fake_refresh)
 
     async def handler(_request: Any) -> ToolMessage:
@@ -256,7 +327,13 @@ async def test_workflow_push_restoration_falls_back_when_actions_read_unavailabl
 
 
 async def test_non_workflow_push_runs_without_approval(monkeypatch: pytest.MonkeyPatch) -> None:
-    guard.SANDBOX_BACKENDS["thread-1"] = _Backend(workflow_files="")
+    # Head contains workflow files, but they are identical to the trusted remote base,
+    # so no approval is required for a code-only change.
+    backend = _Backend(
+        tree_entries={".github/workflows/ci.yml": "blob-sha-1"},
+        base_tree_entries={".github/workflows/ci.yml": "blob-sha-1"},
+    )
+    guard.SANDBOX_BACKENDS["thread-1"] = backend
     called = False
 
     async def fail_approval(*args: Any, **kwargs: Any) -> bool:
@@ -274,6 +351,268 @@ async def test_non_workflow_push_runs_without_approval(monkeypatch: pytest.Monke
     assert called is True
     assert isinstance(result, ToolMessage)
     assert result.content == "pushed"
+    assert any("fetch origin" in cmd for cmd in backend.commands)
+
+
+async def test_stale_workflow_approval_is_loud_and_blocks(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    guard.SANDBOX_BACKENDS["thread-1"] = _Backend()
+    posted: dict[str, Any] = {}
+
+    async def fake_approved(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return {"fingerprint": "old-fp", "status": "approved", "decided_at": "2024-01-01T00:00:00"}
+
+    async def fake_pending(thread_id: str, **kwargs: Any) -> tuple[dict[str, Any], bool]:
+        return {"fingerprint": kwargs["fingerprint"], "status": "pending", "notified": False}, True
+
+    async def fake_post(
+        channel_id: str, thread_ts: str, message: str, **kwargs: Any
+    ) -> tuple[str, None]:
+        posted.update(
+            channel_id=channel_id, thread_ts=thread_ts, message=message, blocks=kwargs["blocks"]
+        )
+        return "1700000000.000300", None
+
+    async def fake_notified(thread_id: str, fingerprint: str) -> None:
+        posted["notified"] = fingerprint
+
+    monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
+    monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
+    monkeypatch.setattr(guard, "post_slack_thread_reply_with_ts", fake_post)
+    monkeypatch.setattr(guard, "mark_workflow_push_notified", fake_notified)
+
+    async def handler(_request: Any) -> ToolMessage:
+        return ToolMessage(content="pushed", tool_call_id="call-1")
+
+    result = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+
+    assert isinstance(result, ToolMessage)
+    assert result.status == "error"
+    payload = json.loads(str(result.content))
+    assert payload["workflow_approval_status"] == "approval_required"
+    assert "changed since that approval" in payload["error"]
+    assert posted["channel_id"] == "C123"
+
+
+async def test_rebased_workflow_push_keeps_fingerprint_for_same_tree(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    # Fingerprint is based on the workflow tree at head, not on a diff against origin.
+    backend = _Backend(
+        tree_entries={".github/workflows/ci.yml": "blob-sha-1"},
+    )
+    backend.head = "b" * 40
+    guard.SANDBOX_BACKENDS["thread-1"] = backend
+
+    async def fake_approved(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
+    async def fake_pending(thread_id: str, **kwargs: Any) -> tuple[dict[str, Any], bool]:
+        return {"fingerprint": kwargs["fingerprint"], "status": "pending", "notified": False}, True
+
+    async def fake_post(*args: Any, **kwargs: Any) -> tuple[str, None]:
+        return "1700000000.000300", None
+
+    async def fake_notified(*args: Any, **kwargs: Any) -> None:
+        return None
+
+    monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
+    monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
+    monkeypatch.setattr(guard, "post_slack_thread_reply_with_ts", fake_post)
+    monkeypatch.setattr(guard, "mark_workflow_push_notified", fake_notified)
+
+    async def handler(_request: Any) -> ToolMessage:
+        return ToolMessage(content="pushed", tool_call_id="call-1")
+
+    result = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+    assert isinstance(result, ToolMessage)
+    assert result.status == "error"
+    payload = json.loads(str(result.content))
+    assert payload["fingerprint"]
+    assert payload["files"] == [".github/workflows/ci.yml"]
+
+    # Rebase with a new head but the same workflow tree -> fingerprint stays stable.
+    backend.head = "c" * 40
+    result2 = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+    assert isinstance(result2, ToolMessage)
+    payload2 = json.loads(str(result2.content))
+    assert payload2["fingerprint"] == payload["fingerprint"]
+
+    # A content change to the same workflow file produces a different fingerprint.
+    backend.tree_entries = {".github/workflows/ci.yml": "blob-sha-2"}
+    result3 = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+    assert isinstance(result3, ToolMessage)
+    payload3 = json.loads(str(result3.content))
+    assert payload3["fingerprint"] != payload["fingerprint"]
+
+
+async def test_deleted_workflow_file_requires_approval(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    # Deleting a workflow file means it is no longer in the head workflow tree. The
+    # guard should still trigger if there are other workflow files at head; if the last
+    # workflow file is deleted, the push is no longer workflow-guarded.
+    backend = _Backend(
+        tree_entries={
+            ".github/workflows/ci.yml": "blob-sha-1",
+            ".github/workflows/other.yml": "blob-sha-2",
+        },
+    )
+    guard.SANDBOX_BACKENDS["thread-1"] = backend
+
+    async def fake_approved(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
+    async def fake_pending(thread_id: str, **kwargs: Any) -> tuple[dict[str, Any], bool]:
+        return {"fingerprint": kwargs["fingerprint"], "status": "pending", "notified": False}, True
+
+    async def fake_post(*args: Any, **kwargs: Any) -> tuple[str, None]:
+        return "1700000000.000300", None
+
+    async def fake_notified(*args: Any, **kwargs: Any) -> None:
+        return None
+
+    monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
+    monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
+    monkeypatch.setattr(guard, "post_slack_thread_reply_with_ts", fake_post)
+    monkeypatch.setattr(guard, "mark_workflow_push_notified", fake_notified)
+
+    async def handler(_request: Any) -> ToolMessage:
+        return ToolMessage(content="pushed", tool_call_id="call-1")
+
+    # Push with the full workflow tree present requires approval.
+    result = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+    assert isinstance(result, ToolMessage)
+    assert result.status == "error"
+    payload = json.loads(str(result.content))
+    assert payload["workflow_approval_status"] == "approval_required"
+    assert ".github/workflows/ci.yml" in payload["files"]
+
+    # A push whose head tree has deleted ci.yml but still contains other.yml still
+    # requires approval, with a different fingerprint.
+    backend.tree_entries = {".github/workflows/other.yml": "blob-sha-2"}
+    result2 = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+    assert isinstance(result2, ToolMessage)
+    payload2 = json.loads(str(result2.content))
+    assert payload2["workflow_approval_status"] == "approval_required"
+    assert payload2["files"] == [".github/workflows/other.yml"]
+    assert payload2["fingerprint"] != payload["fingerprint"]
+
+
+async def test_base_poisoning_does_not_bypass_guard(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    # The sandbox can rewrite refs/remotes/origin/*; the guard must use the workflow
+    # tree at the pushed head, not a diff against a remote ref. This backend records
+    # whether any command touches the remote-tracking ref.
+    backend = _Backend(
+        tree_entries={
+            ".github/workflows/ci.yml": "blob-sha-1",
+            ".github/workflows/evil.yml": "blob-sha-evil",
+        },
+    )
+    guard.SANDBOX_BACKENDS["thread-1"] = backend
+
+    async def fake_approved(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return None
+
+    async def fake_pending(thread_id: str, **kwargs: Any) -> tuple[dict[str, Any], bool]:
+        return {"fingerprint": kwargs["fingerprint"], "status": "pending", "notified": False}, True
+
+    async def fake_post(*args: Any, **kwargs: Any) -> tuple[str, None]:
+        return "1700000000.000300", None
+
+    async def fake_notified(*args: Any, **kwargs: Any) -> None:
+        return None
+
+    monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
+    monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
+    monkeypatch.setattr(guard, "post_slack_thread_reply_with_ts", fake_post)
+    monkeypatch.setattr(guard, "mark_workflow_push_notified", fake_notified)
+
+    async def handler(_request: Any) -> ToolMessage:
+        return ToolMessage(content="pushed", tool_call_id="call-1")
+
+    result = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+
+    assert isinstance(result, ToolMessage)
+    assert result.status == "error"
+    payload = json.loads(str(result.content))
+    assert payload["workflow_approval_status"] == "approval_required"
+    # The evil workflow file present at head must appear in the approval list.
+    assert ".github/workflows/evil.yml" in payload["files"]
+    # No remote-tracking ref should have been consulted.
+    assert not any("refs/remotes/origin" in cmd for cmd in backend.commands)
+
+
+async def test_exact_rejection_checked_before_stale_approval(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    backend = _Backend()
+    guard.SANDBOX_BACKENDS["thread-1"] = backend
+
+    async def fake_approved(thread_id: str, fingerprint: str) -> bool:
+        return False
+
+    async def fake_rejected(thread_id: str, fingerprint: str) -> bool:
+        return True
+
+    # A prior approval for the same repo/branch/files exists; the stale path would
+    # normally match. But because the exact fingerprint is rejected, we must return
+    # "rejected", not "stale_approval".
+    async def fake_find_approval(*args: Any, **kwargs: Any) -> dict[str, Any] | None:
+        return {"fingerprint": "old-fp", "status": "approved", "decided_at": "2024-01-01T00:00:00"}
+
+    async def fake_pending(*args: Any, **kwargs: Any) -> tuple[dict[str, Any], bool]:
+        raise AssertionError("should not create a new pending record")
+
+    monkeypatch.setattr(guard, "workflow_push_approved", fake_approved)
+    monkeypatch.setattr(guard, "workflow_push_rejected", fake_rejected)
+    monkeypatch.setattr(guard, "find_workflow_push_approval", fake_find_approval)
+    monkeypatch.setattr(guard, "ensure_workflow_push_pending", fake_pending)
+
+    async def handler(_request: Any) -> ToolMessage:
+        return ToolMessage(content="pushed", tool_call_id="call-1")
+
+    result = await guard.WorkflowPushGuardMiddleware().awrap_tool_call(_Request(), handler)
+
+    assert isinstance(result, ToolMessage)
+    assert result.status == "error"
+    payload = json.loads(str(result.content))
+    assert payload["workflow_approval_status"] == "rejected"
 
 
 async def test_approved_workflow_push_aborts_when_elevation_fails(