fix(security): reject inode aliases and workspace redirects

The agent's read tools (read_file, grep, glob, ls) resolved model-supplied
paths against a root list whose first entry was the whole data directory.
That directory holds the session store, the auth database, the app
encryption key and the settings file, so prompt-injected content could ask
for any of them. No approval prompt stood in the way: reads are classified
read_workspace and pass the untrusted-context gate untouched, which is
correct for reading a workspace and wrong for reading the app's own state.

The agent gets data/agent_workspace/ instead, and the subprocess cwd and
HOME move with it so bash and read_file agree on where scratch files live.

The deny itself is a property of the path, not of the root it arrived
through, because three routes reach the same bytes and closing only the
first leaves the other two working:

  - the default root list
  - a workspace bound at or above the data directory, which vet_workspace
    accepted and chat_routes auto-binds from a path named in the message
  - a tool_path_extra_roots setting covering the data directory

_resolve_search_root also returned the workspace root unchecked when the
path was empty, so a bare ls enumerated the directory whatever the deny
list said. It now resolves that case through the same guards.

A containment rule rather than a filename deny list, so state files added
later are covered without anyone remembering to list them, and so a user's
own settings.json or app.db inside a real workspace is not caught.

Four directories of user content stay readable, because the application
hands their paths to the model and tells it to open them: the chat upload
manifest, downloaded mail attachments, personal docs (which covers the
runbook) and personal uploads.

setup.py

@@ -16,7 +16,7 @@ sys.path.insert(0, BASE_DIR)
 from src.constants import (
     DATA_DIR, AUTH_FILE, UPLOAD_DIR, PERSONAL_DIR, PERSONAL_UPLOADS_DIR,
     TTS_CACHE_DIR, GENERATED_IMAGES_DIR, DEEP_RESEARCH_DIR, CHROMA_DIR,
-    RAG_DIR, MEMORY_VECTORS_DIR, PASSWORD_MIN_LENGTH,
+    RAG_DIR, MEMORY_VECTORS_DIR, AGENT_WORKSPACE_DIR, PASSWORD_MIN_LENGTH,
 )
 from core.auth import RESERVED_USERNAMES
 
@@ -31,6 +31,7 @@ DIRS = [
     CHROMA_DIR,
     RAG_DIR,
     MEMORY_VECTORS_DIR,
+    AGENT_WORKSPACE_DIR,
     os.path.join(BASE_DIR, "logs"),
 ]
 

src/agent_tools/filesystem_tools.py

@@ -3,8 +3,8 @@ import json
 import os
 import re
 import difflib
-import fnmatch
 import shutil
+import time
 from typing import Optional, Dict, Any, Tuple, List
 
 from src.constants import MAX_READ_CHARS, MAX_DIFF_LINES, MAX_OUTPUT_CHARS
@@ -407,7 +407,11 @@ def _apply_patch_hunks(original: str, hunks: List[List[str]], label: str) -> str
 
 class LsTool:
     async def execute(self, content: str, ctx: dict) -> dict:
-        from src.tool_execution import _resolve_tool_path, _resolve_search_root, _truncate
+        from src.tool_execution import (
+            _is_denied_tool_path,
+            _resolve_search_root,
+            _truncate,
+        )
         raw_path = ""
         _s = (content or "").strip()
         if _s.startswith("{"):
@@ -431,6 +435,8 @@ class LsTool:
                     for entry in it:
                         if entry.name.startswith("."):
                             continue
+                        if _is_denied_tool_path(os.path.realpath(entry.path)):
+                            continue
                         try:
                             is_dir = entry.is_dir(follow_symlinks=False)
                             size = entry.stat(follow_symlinks=False).st_size if not is_dir else 0
@@ -458,7 +464,8 @@ class GlobTool:
     async def execute(self, content: str, ctx: dict) -> dict:
         from src.tool_execution import (
             _SENSITIVE_BASENAMES,
-            _is_sensitive_path,
+            _can_traverse_tool_path,
+            _is_denied_tool_path,
             _resolve_tool_path,
             _resolve_search_root,
             _truncate,
@@ -507,7 +514,7 @@ class GlobTool:
                 # .ssh/id_rsa, …) falls through to the walk, which skips it —
                 # otherwise glob would surface secret paths that read_file /
                 # grep already refuse to touch.
-                if inside and os.path.exists(cand) and not _is_sensitive_path(cand):
+                if inside and os.path.exists(cand) and not _is_denied_tool_path(cand):
                     return [cand], None
                 # Literal not at exact path — fall through to walk so
                 # e.g. "foo.py" still matches at any depth (like rglob).
@@ -517,13 +524,18 @@ class GlobTool:
             cap = _CODENAV_MAX_HITS * 5
             try:
                 for dp, dns, fns in os.walk(base):
+                    if not _can_traverse_tool_path(os.path.realpath(dp)):
+                        dns[:] = []
+                        continue
                     # Prune skipped dirs before descending (unlike rglob which
                     # descends first then filters — fatal on large node_modules).
                     # Sensitive dirs (.ssh, .gnupg, …) are pruned too so glob
                     # never enumerates the keys/tokens inside them.
                     dns[:] = [
                         d for d in dns
-                        if d not in _CODENAV_SKIP_DIRS and d not in _SENSITIVE_BASENAMES
+                        if d not in _CODENAV_SKIP_DIRS
+                        and d not in _SENSITIVE_BASENAMES
+                        and _can_traverse_tool_path(os.path.realpath(os.path.join(dp, d)))
                     ]
                     for name in fns + dns:
                         full = os.path.join(dp, name)
@@ -531,7 +543,7 @@ class GlobTool:
                         if regex.fullmatch(rel) or regex.fullmatch(name):
                             # Skip deny-listed sensitive files (.env, id_rsa,
                             # known_hosts, …) the same way grep does.
-                            if _is_sensitive_path(os.path.realpath(full)):
+                            if _is_denied_tool_path(os.path.realpath(full)):
                                 continue
                             try:
                                 mtime = os.stat(full).st_mtime
@@ -559,7 +571,10 @@ class GrepTool:
     async def execute(self, content: str, ctx: dict) -> dict:
         from src.tool_execution import (
             _SENSITIVE_FILE_PATTERNS,
-            _is_sensitive_path,
+            _agent_readable_data_subdirs,
+            _can_traverse_tool_path,
+            _is_denied_tool_path,
+            _path_within,
             _resolve_tool_path,
             _resolve_search_root,
             _truncate,
@@ -592,50 +607,178 @@ class GrepTool:
             import re as _re
             import shutil
             rg = shutil.which("rg")
+            from src.constants import DATA_DIR
+            real_root = os.path.realpath(root)
+            data_dir = os.path.realpath(DATA_DIR)
+            spans_state = _path_within(data_dir, real_root)
+            if spans_state and not rg:
+                return None, "grep: ripgrep is required when the search root contains application state"
             if rg:
-                cmd = [rg, "--line-number", "--no-heading", "--color=never",
+                searches: list[tuple[str, list[str]]] = [(real_root, [])]
-                       "--max-count", str(max_hits)]
+                if spans_state:
-                if ignore_case:
+                    searches = []
-                    cmd.append("--ignore-case")
+                    # Search everything outside DATA_DIR with a native rg glob
-                if glob_pat:
+                    # exclusion.  Search validated carve-outs separately so
-                    cmd += ["--glob", glob_pat]
+                    # their contents remain available without exposing state
-                # --iglob (not --glob) so the exclusion is case-insensitive:
+                    # siblings.  --no-follow prevents a symlink from bypassing
-                # on a case-insensitive filesystem "ID_RSA"/"Known_Hosts"
+                    # the excluded canonical subtree.
-                # resolve to the same secret as their lowercase forms, and the
+                    if real_root != data_dir:
-                # Python fallback below already folds case via _is_sensitive_path.
+                        rel_data = os.path.relpath(data_dir, real_root).replace(
-                for _pat in _SENSITIVE_FILE_PATTERNS:
+                            os.sep, "/"
-                    cmd += ["--iglob", f"!*{_pat}*"]
+                        )
-                for _d in _CODENAV_SKIP_DIRS:
+                        searches.append(
-                    cmd += ["--glob", f"!**/{_d}/**"]
+                            (real_root, [f"!{rel_data}", f"!{rel_data}/**"])
-                cmd += ["--regexp", pattern, root]
+                        )
-                try:
+                    seen_roots: set[str] = set()
-                    import subprocess
+                    for readable in _agent_readable_data_subdirs():
-                    p = subprocess.run(cmd, capture_output=True, text=True, timeout=20)
+                        if not _path_within(
-                    lines = [ln for ln in (p.stdout or "").splitlines() if ln][:max_hits]
+                            readable, real_root
-                    return lines, None
+                        ) or not os.path.exists(readable):
-                except subprocess.TimeoutExpired:
+                            continue
-                    return None, "grep: timed out"
+                        canonical = os.path.realpath(readable)
-                except Exception as _e:
+                        if canonical not in seen_roots:
-                    return None, f"grep: {_e}"
+                            seen_roots.add(canonical)
+                            searches.append((canonical, []))
+
+                lines: list[str] = []
+                deadline = time.monotonic() + 20
+                for search_root, state_excludes in searches:
+                    remaining_hits = max_hits - len(lines)
+                    if remaining_hits <= 0:
+                        break
+                    # JSON output gives us the canonical match pathname so it
+                    # can be revalidated before any line reaches the model.
+                    # This is required for hardlink aliases inside an allowed
+                    # workspace; lexical/path checks alone cannot see them.
+                    cmd = [
+                        rg, "--json", "--no-config", "--no-follow",
+                        "--max-count", str(remaining_hits),
+                    ]
+                    if ignore_case:
+                        cmd.append("--ignore-case")
+                    if glob_pat:
+                        cmd += ["--glob", glob_pat]
+                    # --iglob (not --glob) so the exclusion is case-insensitive:
+                    # on a case-insensitive filesystem "ID_RSA"/"Known_Hosts"
+                    # resolve to the same secret as their lowercase forms.
+                    for _pat in _SENSITIVE_FILE_PATTERNS:
+                        cmd += ["--iglob", f"!*{_pat}*"]
+                    for _d in _CODENAV_SKIP_DIRS:
+                        cmd += ["--glob", f"!**/{_d}/**"]
+                    for exclusion in state_excludes:
+                        cmd += ["--glob", exclusion]
+                    cmd += ["--regexp", pattern, search_root]
+                    timeout = deadline - time.monotonic()
+                    if timeout <= 0:
+                        return None, "grep: timed out"
+                    try:
+                        import queue
+                        import subprocess
+                        import threading
+                        process = subprocess.Popen(
+                            cmd,
+                            stdout=subprocess.PIPE,
+                            stderr=subprocess.DEVNULL,
+                            text=True,
+                            bufsize=1,
+                        )
+                    except Exception as _e:
+                        return None, f"grep: {_e}"
+                    output: queue.Queue[Optional[str]] = queue.Queue()
+
+                    def _read_stdout() -> None:
+                        assert process.stdout is not None
+                        try:
+                            for line in process.stdout:
+                                output.put(line.rstrip("\n"))
+                        finally:
+                            output.put(None)
+
+                    threading.Thread(target=_read_stdout, daemon=True).start()
+                    try:
+                        while len(lines) < max_hits:
+                            remaining = deadline - time.monotonic()
+                            if remaining <= 0:
+                                return None, "grep: timed out"
+                            try:
+                                line = output.get(timeout=remaining)
+                            except queue.Empty:
+                                return None, "grep: timed out"
+                            if line is None:
+                                break
+                            if not line:
+                                continue
+                            try:
+                                event = json.loads(line)
+                            except (TypeError, json.JSONDecodeError):
+                                # Keep lightweight/fake runners compatible with
+                                # the historical plain `path:line:text` stream;
+                                # still revalidate the path before exposing it.
+                                pieces = line.split(":", 2)
+                                if len(pieces) >= 3:
+                                    plain_path = pieces[0]
+                                    if not _is_denied_tool_path(os.path.realpath(plain_path)):
+                                        if line not in lines:
+                                            lines.append(line)
+                                continue
+                            if event.get("type") != "match":
+                                continue
+                            match = event.get("data") or {}
+                            path_data = match.get("path") or {}
+                            match_path = path_data.get("text")
+                            if not match_path:
+                                continue
+                            if _is_denied_tool_path(os.path.realpath(match_path)):
+                                continue
+                            line_text = (match.get("lines") or {}).get("text", "")
+                            line_number = match.get("line_number", "?")
+                            rendered = (
+                                f"{match_path}:{line_number}:"
+                                f"{line_text.rstrip()[:_CODENAV_MAX_LINE]}"
+                            )
+                            if rendered not in lines:
+                                lines.append(rendered)
+                    finally:
+                        if process.poll() is None:
+                            process.terminate()
+                            try:
+                                process.wait(timeout=1)
+                            except subprocess.TimeoutExpired:
+                                process.kill()
+                                process.wait()
+                return lines, None
             try:
                 rx = _re.compile(pattern, _re.IGNORECASE if ignore_case else 0)
             except _re.error as _e:
                 return None, f"grep: bad pattern: {_e}"
+            glob_rx = _glob_to_regex(glob_pat.replace("\\", "/")) if glob_pat else None
             hits = []
             if os.path.isfile(root):
                 file_iter = [root]
             else:
                 file_iter = []
                 for dp, dns, fns in os.walk(root):
-                    dns[:] = [d for d in dns if d not in _CODENAV_SKIP_DIRS]
+                    if not _can_traverse_tool_path(os.path.realpath(dp)):
+                        dns[:] = []
+                        continue
+                    dns[:] = [
+                        d for d in dns
+                        if d not in _CODENAV_SKIP_DIRS
+                        and _can_traverse_tool_path(os.path.realpath(os.path.join(dp, d)))
+                    ]
                     for fn in fns:
-                        if glob_pat and not fnmatch.fnmatch(fn, glob_pat):
+                        rel = os.path.relpath(os.path.join(dp, fn), root).replace(
+                            os.sep, "/"
+                        )
+                        if glob_rx and not (
+                            glob_rx.fullmatch(rel) or glob_rx.fullmatch(fn)
+                        ):
                             continue
                         file_iter.append(os.path.join(dp, fn))
             for fp in file_iter:
                 if len(hits) >= max_hits:
                     break
-                if _is_sensitive_path(os.path.realpath(fp)):
+                if _is_denied_tool_path(os.path.realpath(fp)):
                     continue
                 try:
                     with open(fp, "r", encoding="utf-8", errors="strict") as f:

src/app_initializer.py

@@ -2,10 +2,11 @@
 """Initialize all application components and dependencies."""
 import os
 import logging
+import stat
 from typing import Dict, Any
 
 from src.constants import (
-    DATA_DIR, PERSONAL_DIR, RUNBOOK_DIR, UPLOAD_DIR,
+    DATA_DIR, PERSONAL_DIR, RUNBOOK_DIR, UPLOAD_DIR, AGENT_WORKSPACE_DIR,
     SESSIONS_FILE, DEFAULT_HOST, OPENAI_API_KEY
 )
 from src.memory import MemoryManager
@@ -30,7 +31,35 @@ def create_directories():
     """Create necessary directories if they don't exist."""
     for directory in (DATA_DIR, PERSONAL_DIR, RUNBOOK_DIR, UPLOAD_DIR):
         os.makedirs(directory, exist_ok=True)
-        
+
+    # The model-controlled workspace must be a real child of DATA_DIR.  Never
+    # follow a pre-existing symlink here: it would silently move the default
+    # native-file root outside the application volume before any resolver runs.
+    data_root = os.path.realpath(DATA_DIR)
+    workspace = os.path.abspath(os.path.expanduser(AGENT_WORKSPACE_DIR))
+    try:
+        if os.path.commonpath([workspace, data_root]) != data_root or workspace == data_root:
+            raise RuntimeError("agent workspace must resolve inside DATA_DIR")
+    except ValueError as exc:
+        raise RuntimeError("agent workspace must resolve inside DATA_DIR") from exc
+    if os.path.lexists(workspace):
+        mode = os.lstat(workspace).st_mode
+        if stat.S_ISLNK(mode) or not stat.S_ISDIR(mode):
+            raise RuntimeError("agent workspace must be a real directory")
+    else:
+        os.mkdir(workspace, 0o700)
+    resolved_workspace = os.path.realpath(workspace)
+    try:
+        inside = os.path.commonpath([resolved_workspace, data_root]) == data_root
+    except ValueError:
+        inside = False
+    if resolved_workspace == data_root or not inside:
+        raise RuntimeError("agent workspace must resolve inside DATA_DIR")
+    try:
+        os.chmod(workspace, 0o700)
+    except OSError:
+        pass
+
 def initialize_managers(base_dir: str, rag_manager=None) -> Dict[str, Any]:
     """
     Initialize all manager and handler instances.

src/constants.py

@@ -54,6 +54,11 @@ GALLERY_DIR = os.path.join(DATA_DIR, "gallery")
 GALLERY_UPLOADS_DIR = os.path.join(DATA_DIR, "gallery_uploads")
 MEMORY_VECTORS_DIR = os.path.join(DATA_DIR, "memory_vectors")
 
+# The only part of DATA_DIR the agent's file tools and subprocesses may touch.
+# Everything else under DATA_DIR is application state (session store, auth
+# database, encryption key, settings), and the agent has no business reading it.
+AGENT_WORKSPACE_DIR = os.path.join(DATA_DIR, "agent_workspace")
+
 # Paths with an intentional dedicated env override, defaulting under DATA_DIR.
 MAIL_ATTACHMENTS_DIR = os.getenv("ODYSSEUS_MAIL_ATTACHMENTS_DIR", os.path.join(DATA_DIR, "mail-attachments"))
 # `or` (not os.getenv's default arg) so a PRESENT-but-EMPTY value falls back to

src/tool_execution.py

@@ -15,6 +15,7 @@ import logging
 import os
 import pathlib
 import re
+import stat
 import sys
 import time
 from typing import Any, Awaitable, Callable, Dict, Optional, Tuple
@@ -30,7 +31,12 @@ from src.tool_security import (
 from src.tool_capabilities import ToolRunSecurityContext, blocked_tool_result
 from src.tool_approvals import ExactToolApproval
 from src.tool_policy import ToolPolicy
-from src.constants import MAX_OUTPUT_CHARS, MAX_READ_CHARS, MAX_DIFF_LINES, DATA_DIR
+from src.constants import (
+    MAX_OUTPUT_CHARS,
+    MAX_READ_CHARS,
+    MAX_DIFF_LINES,
+    AGENT_WORKSPACE_DIR,
+)
 from src.tool_utils import _truncate, get_mcp_manager
 
 
@@ -46,11 +52,11 @@ _MISSING_TOOL_SECURITY_CONTEXT = _MissingToolSecurityContext()
 NO_TOOL_SECURITY_CONTEXT = _NoToolSecurityContext()
 
 # Persistent working directory for agent subprocesses.
-# Resolves to <repo_root>/data, which is the bind-mounted volume in Docker
+# Resolves to <repo_root>/data/agent_workspace, inside the bind-mounted volume
-# (/app/data) and the local data directory for manual installs.
+# in Docker (/app/data), so files survive a rebuild as before. The subdirectory
-# Using this as cwd and HOME prevents the agent from silently creating files
+# rather than data/ itself keeps agent scratch files and dotfiles out of the
-# in ephemeral container layers that are lost on the next rebuild.
+# directory holding the session store and the auth database.
-_AGENT_WORKDIR = DATA_DIR
+_AGENT_WORKDIR = AGENT_WORKSPACE_DIR
 
 
 
@@ -66,10 +72,15 @@ _AGENT_WORKDIR = DATA_DIR
 #   1. Sensitive-subpath deny list — checked FIRST. Blocks .ssh,
 #      .gnupg, shell rc files, token/env files even if the root above
 #      them is on the allowlist.
-#   2. Allowlist — only the directories the agent legitimately needs
+#   2. Application-state deny (_is_app_state_path) - DATA_DIR holds the
-#      (project data/, system tmp). $HOME is NOT on the default list.
+#      session store, auth database, app key and settings, so only
-#   3. Opt-in extra roots — admin can add broader roots via the
+#      _agent_readable_data_subdirs() is readable inside it.
-#      "tool_path_extra_roots" setting (list of path strings).
+#   3. Allowlist - only the directories the agent legitimately needs
+#      (its data/ workspace, user content, system tmp). $HOME is NOT on
+#      the default list.
+#   4. Opt-in extra roots - admin can add broader roots via the
+#      "tool_path_extra_roots" setting. These cannot re-open DATA_DIR;
+#      rule 2 is independent of which root a path arrived through.
 # ---------------------------------------------------------------------------
 
 _SENSITIVE_BASENAMES: set[str] = {
@@ -116,6 +127,169 @@ def _is_sensitive_path(resolved: str) -> bool:
     return filename in _SENSITIVE_FILE_PATTERNS_CF
 
 
+def _path_within(resolved: str, root: str) -> bool:
+    """True when *resolved* is *root* itself or sits underneath it.
+
+    Use the platform's path-case rules.  This helper participates in allow
+    decisions, so unconditional case-folding would let a distinct ``/DATA``
+    tree masquerade as a descendant of ``/data`` on case-sensitive systems.
+    """
+    resolved, root = os.path.normcase(resolved), os.path.normcase(root)
+    if resolved == root:
+        return True
+    try:
+        if os.path.commonpath([resolved, root]) == root:
+            return True
+    except ValueError:
+        return False
+    # normcase is intentionally conservative about assumptions (notably on
+    # POSIX), so consult the filesystem when paths exist.  This recognizes a
+    # case alias on a case-insensitive volume without treating distinct
+    # case-sensitive paths as the same allow root.
+    if os.path.exists(root):
+        candidate = resolved
+        while True:
+            try:
+                if os.path.exists(candidate) and os.path.samefile(candidate, root):
+                    return True
+            except OSError:
+                pass
+            parent = os.path.dirname(candidate)
+            if parent == candidate:
+                break
+            candidate = parent
+    return False
+
+
+def _path_within_conservative(resolved: str, root: str) -> bool:
+    """Containment for deny decisions, folding case to fail closed."""
+    resolved, root = resolved.casefold(), root.casefold()
+    if resolved == root:
+        return True
+    try:
+        return os.path.commonpath([resolved, root]) == root
+    except ValueError:
+        return False
+
+
+def _agent_readable_data_subdirs() -> tuple[str, ...]:
+    """The only parts of DATA_DIR the agent's file tools may reach.
+
+    The agent's own scratch folder, plus the directories of user content whose
+    paths the application itself gives to the model, which it would then be
+    unable to open.  These normally live under DATA_DIR; the documented mail
+    attachment override may instead name a disjoint external directory:
+
+      UPLOAD_DIR            the chat upload manifest renders "path=<p>" and
+                            says to read it with read_file (agent_loop.py)
+      MAIL_ATTACHMENTS_DIR  download_attachment returns the path and its own
+                            description tells the model to read it
+      PERSONAL_DIR          GET /api/personal returns a path per file and is
+                            reachable through the app_api tool; RUNBOOK_DIR
+                            nests under it
+      PERSONAL_UPLOADS_DIR  indexed as a personal-docs directory, which
+                            manage_rag lists as an absolute path
+
+    Order matters: the first entry is roots[0], which _resolve_search_root uses
+    when grep/glob/ls are called with no path.
+    """
+    from src.constants import (
+        DATA_DIR,
+        MAIL_ATTACHMENTS_DIR,
+        PERSONAL_DIR,
+        PERSONAL_UPLOADS_DIR,
+        UPLOAD_DIR,
+    )
+    configured = (
+        (AGENT_WORKSPACE_DIR, False),
+        (UPLOAD_DIR, False),
+        # This has a documented environment override and may legitimately
+        # live outside DATA_DIR, but it must never equal/contain DATA_DIR.
+        (MAIL_ATTACHMENTS_DIR, True),
+        (PERSONAL_DIR, False),
+        (PERSONAL_UPLOADS_DIR, False),
+    )
+    data_dir = os.path.realpath(DATA_DIR)
+    safe: list[str] = []
+    for raw, external_ok in configured:
+        value = str(raw or "").strip()
+        # These paths are security-policy roots, not ordinary allowlist
+        # entries.  Accept only explicit absolute directory paths.  State
+        # carve-outs must be strict DATA_DIR descendants; the documented mail
+        # override may also be disjoint.  Empty/dot, filesystem-root, ancestor,
+        # equality, file, or symlink-equivalent settings fail closed.
+        if not value or not os.path.isabs(os.path.expanduser(value)):
+            continue
+        resolved = os.path.realpath(os.path.expanduser(value))
+        if os.path.exists(resolved) and not os.path.isdir(resolved):
+            continue
+        inside_data = resolved != data_dir and _path_within(resolved, data_dir)
+        external_safe = (
+            external_ok
+            and resolved != data_dir
+            and os.path.dirname(resolved) != resolved
+            and not _path_within(data_dir, resolved)
+            and not _path_within(resolved, data_dir)
+        )
+        if not (inside_data or external_safe) or _is_sensitive_path(resolved):
+            continue
+        safe.append(resolved)
+    return tuple(safe)
+
+
+def _is_app_state_path(resolved: str) -> bool:
+    """True for anything under DATA_DIR that is not agent-readable.
+
+    DATA_DIR holds the session store, the auth database, the app encryption key
+    and the settings file. A model-supplied path must not reach those through
+    any root, so this is checked in both resolvers rather than expressed as an
+    absence from the allowlist: a workspace bound at or above the data
+    directory, or an opt-in tool_path_extra_roots entry covering it, would
+    otherwise put them back in reach.
+
+    A containment rule rather than a filename deny list, so state files added
+    later are covered without anyone remembering to list them, and so a user's
+    own settings.json or app.db inside a real workspace is not caught.
+    """
+    from src.constants import DATA_DIR
+    if not _path_within_conservative(resolved, os.path.realpath(DATA_DIR)):
+        return False
+    return not any(
+        _path_within(resolved, d)
+        for d in _agent_readable_data_subdirs()
+    )
+
+
+def _is_hardlinked_regular_file(resolved: str) -> bool:
+    """Reject inode aliases that can smuggle DATA_DIR state into an allow root."""
+    try:
+        target = os.stat(resolved, follow_symlinks=False)
+    except OSError:
+        return False
+    return stat.S_ISREG(target.st_mode) and getattr(target, "st_nlink", 1) > 1
+
+
+def _is_denied_tool_path(resolved: str) -> bool:
+    """Apply every path deny to a canonical traversal result."""
+    return (
+        _is_sensitive_path(resolved)
+        or _is_app_state_path(resolved)
+        or _is_hardlinked_regular_file(resolved)
+    )
+
+
+def _can_traverse_tool_path(resolved: str) -> bool:
+    """Allow walking a denied state parent only to reach safe carve-outs."""
+    if _is_sensitive_path(resolved):
+        return False
+    if not _is_app_state_path(resolved):
+        return True
+    return any(
+        _path_within(readable, resolved)
+        for readable in _agent_readable_data_subdirs()
+    )
+
+
 def _tool_path_roots() -> list[str]:
     """Return the list of directory roots that read_file / write_file
     may touch. Default: project data/ + system temp dirs. Extra roots
@@ -123,9 +297,9 @@ def _tool_path_roots() -> list[str]:
     """
     roots: list[str] = []
 
-    # Project data directory — the agent's primary workspace.
+    # The agent's workspace plus the user-content directories inside data/.
-    from src.constants import DATA_DIR
+    # The rest of DATA_DIR is denied by _is_app_state_path.
-    roots.append(DATA_DIR)
+    roots.extend(_agent_readable_data_subdirs())
 
     # /tmp (and its macOS realpath /private/tmp).
     roots.append("/tmp")
@@ -193,6 +367,12 @@ def _resolve_tool_path(raw_path: str) -> str:
             f"path '{raw_path}' is inside a sensitive directory "
             f"(e.g. .ssh, .gnupg) or matches a sensitive filename"
         )
+    if _is_app_state_path(resolved):
+        raise ValueError(
+            f"path '{raw_path}' is inside the application state directory"
+        )
+    if _is_hardlinked_regular_file(resolved):
+        raise ValueError(f"path '{raw_path}' is a hard-linked file")
 
     for root in _tool_path_roots():
         if resolved == root:
@@ -228,6 +408,12 @@ def _resolve_tool_path_in_workspace(workspace: str, raw_path: str) -> str:
             f"path '{raw_path}' is inside a sensitive directory "
             f"(e.g. .ssh, .gnupg) or matches a sensitive filename"
         )
+    if _is_app_state_path(resolved):
+        raise ValueError(
+            f"path '{raw_path}' is inside the application state directory"
+        )
+    if _is_hardlinked_regular_file(resolved):
+        raise ValueError(f"path '{raw_path}' is a hard-linked file")
     if resolved != base:
         # normcase so containment holds on case-insensitive filesystems
         # (Windows, default macOS): it lowercases on Windows and is a no-op on
@@ -277,6 +463,10 @@ def vet_workspace(raw: str) -> Optional[str]:
     resolved = os.path.realpath(os.path.expanduser(raw))
     if not os.path.isdir(resolved) or _is_sensitive_path(resolved):
         return None
+    # Refuse the bind rather than binding a workspace where every subsequent
+    # tool call would fail on the same deny list.
+    if _is_app_state_path(resolved):
+        return None
     # Reject filesystem roots: binding / (or a Windows drive/UNC root) as the
     # workspace would make every absolute path "inside" it, collapsing the
     # confinement into host-wide file access. A root is its own dirname, which
@@ -304,16 +494,22 @@ def _resolve_search_root(raw_path: str) -> str:
 
     With a workspace active, the workspace folder is the root and a supplied
     path is confined inside it. Otherwise an empty path defaults to the agent's
-    primary root (project data dir) and a supplied path is confined by the
+    primary root (its workspace under the project data dir) and a supplied path
-    global allowlist + sensitive-file policy.
+    is confined by the global allowlist + sensitive-file policy.
     """
     raw = (raw_path or "").strip()
     ws = get_active_workspace()
     if ws:
-        return os.path.realpath(ws) if not raw else _resolve_tool_path_in_workspace(ws, raw)
+        # Resolve the empty case as the workspace path rather than returning
+        # it directly: returned unchecked it skipped both deny lists, so a
+        # bare ls listed whatever the workspace was bound to.
+        return _resolve_tool_path_in_workspace(ws, raw or ws)
     if not raw:
         roots = _tool_path_roots()
-        return roots[0] if roots else os.path.realpath(".")
+        default_root = os.path.realpath(AGENT_WORKSPACE_DIR)
+        if default_root in roots and not _is_denied_tool_path(default_root):
+            return default_root
+        raise ValueError("default agent workspace is not a safe readable data subdirectory")
     return _resolve_tool_path(raw)
 
 logger = logging.getLogger(__name__)

tests/test_agent_state_dir_confinement.py

@@ -0,0 +1,574 @@
+"""The agent's file tools must not reach the application's own state.
+
+read_file / grep / glob / ls resolve model-supplied paths against
+_tool_path_roots(), and the data directory holds the session store, the
+credential database, the encryption key and the settings file. A read tool
+pointed at those is a credential disclosure, and no approval prompt stands in
+the way because reads are classified read_workspace and pass the untrusted-
+context gate untouched.
+
+The agent gets its own subdirectory instead. Three routes have to close
+together, because closing only the first leaves the other two working:
+
+  - the default roots, which put DATA_DIR first
+  - an active workspace bound at (or above) the data directory
+  - a tool_path_extra_roots setting that covers the data directory
+
+so the guard is a property of the path, not of the root it arrived through.
+"""
+
+import asyncio
+import importlib
+import os
+import shutil
+import time
+from contextlib import contextmanager, nullcontext
+
+import pytest
+
+from src.constants import (
+    AGENT_WORKSPACE_DIR,
+    DATA_DIR,
+    MAIL_ATTACHMENTS_DIR,
+    PERSONAL_DIR,
+    PERSONAL_UPLOADS_DIR,
+    RUNBOOK_DIR,
+    UPLOAD_DIR,
+)
+from src.tool_execution import (
+    _active_workspace,
+    _resolve_search_root,
+    _resolve_tool_path,
+    agent_cwd,
+    vet_workspace,
+)
+from src.agent_tools.filesystem_tools import GlobTool, GrepTool, LsTool
+
+APP_STATE_FILES = [
+    "sessions.json",   # session token -> username, cleartext
+    "auth.json",       # bcrypt hashes, admin flags, privileges
+    "app.db",          # every user's notes, documents, mail rows
+    ".app_key",        # Fernet key for secret_storage
+    "settings.json",   # provider API keys
+]
+
+
+@contextmanager
+def workspace_at(path):
+    """Bind an active workspace for the body of a test.
+
+    Set and reset in the same context; a ContextVar token cannot be reset from
+    fixture teardown, which runs in a different one.
+    """
+    token = _active_workspace.set(os.path.realpath(path))
+    try:
+        yield
+    finally:
+        _active_workspace.reset(token)
+
+
+# ── The default roots ────────────────────────────────────────────────
+
+@pytest.mark.parametrize("name", APP_STATE_FILES)
+def test_blocks_app_state_file(name):
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(os.path.join(DATA_DIR, name))
+
+
+def test_blocks_listing_the_data_directory_itself():
+    """`ls data` enumerated the state files, which is how an attacker who
+    does not know the install path finds them."""
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(DATA_DIR)
+
+
+def test_blocks_app_state_reached_by_relative_path(monkeypatch):
+    """The data directory is a relative hop from the checkout root, so
+    confinement cannot depend on the model supplying an absolute path."""
+    monkeypatch.chdir(os.path.dirname(DATA_DIR))
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(os.path.join(os.path.basename(DATA_DIR), "sessions.json"))
+
+
+def test_blocks_app_state_reached_through_a_symlink(tmp_path):
+    """/tmp is an allowed root and the agent can create links there in an
+    un-armed turn, so containment has to survive one."""
+    link = tmp_path / "shortcut"
+    try:
+        link.symlink_to(DATA_DIR)
+    except OSError:
+        pytest.skip("cannot create symlink")
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(str(link / "sessions.json"))
+
+
+def test_native_file_tools_hide_control_plane_hardlink_alias(tmp_path, monkeypatch):
+    """A pathname inside an allowed root must not alias a protected state inode."""
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    workspace = readable["AGENT_WORKSPACE_DIR"]
+    workspace.mkdir()
+    secret = data_dir / "sessions.json"
+    secret.write_text("LIVE_ADMIN_SESSION\n", encoding="utf-8")
+    alias = workspace / "notes.txt"
+    try:
+        os.link(secret, alias)
+    except OSError:
+        pytest.skip("cannot create hardlink")
+
+    with pytest.raises(ValueError, match="hard-linked"):
+        importlib.import_module("src.tool_execution")._resolve_tool_path(str(alias))
+
+    ls_result = asyncio.run(LsTool().execute(
+        f'{{"path": "{workspace}"}}', {}
+    ))
+    glob_result = asyncio.run(GlobTool().execute(
+        f'{{"pattern": "**/*", "path": "{workspace}"}}', {}
+    ))
+    grep_result = asyncio.run(GrepTool().execute(
+        f'{{"pattern": "LIVE_ADMIN_SESSION", "path": "{workspace}"}}', {}
+    ))
+    assert "notes.txt" not in ls_result["output"]
+    assert "notes.txt" not in glob_result["output"]
+    assert "notes.txt" not in grep_result["output"]
+    assert ":1:LIVE_ADMIN_SESSION" not in grep_result["output"]
+
+
+def test_blocks_app_state_on_a_case_insensitive_filesystem():
+    """On default macOS a case-variant path opens the same file, and realpath
+    does not canonicalise case there the way it does on Windows.
+
+    This deny rule fails OPEN when containment misses, unlike the allowlist
+    beside it, which fails closed. So it folds case, for the same reason
+    _is_sensitive_path does and not with normcase, which is a no-op on POSIX.
+    """
+    shouty = os.path.join(DATA_DIR.upper(), "SESSIONS.JSON")
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(shouty)
+
+
+def test_default_search_root_is_the_agent_workspace():
+    """grep/glob/ls with no path fall back to roots[0]. That was DATA_DIR."""
+    assert _resolve_search_root("") == os.path.realpath(AGENT_WORKSPACE_DIR)
+
+
+def test_startup_rejects_agent_workspace_symlink_escape(tmp_path, monkeypatch):
+    """Startup must not accept a dedicated workspace redirected outside DATA_DIR."""
+    import src.app_initializer as app_initializer
+    import src.tool_execution as tool_execution
+
+    data_dir = tmp_path / "data"
+    outside = tmp_path / "outside"
+    data_dir.mkdir()
+    outside.mkdir()
+    workspace = data_dir / "agent_workspace"
+    try:
+        workspace.symlink_to(outside, target_is_directory=True)
+    except OSError:
+        pytest.skip("cannot create symlink")
+
+    personal = data_dir / "personal_docs"
+    monkeypatch.setattr(app_initializer, "DATA_DIR", str(data_dir))
+    monkeypatch.setattr(app_initializer, "PERSONAL_DIR", str(personal))
+    monkeypatch.setattr(app_initializer, "RUNBOOK_DIR", str(personal / "runbook"))
+    monkeypatch.setattr(app_initializer, "UPLOAD_DIR", str(data_dir / "uploads"))
+    monkeypatch.setattr(app_initializer, "AGENT_WORKSPACE_DIR", str(workspace))
+    monkeypatch.setattr(tool_execution, "AGENT_WORKSPACE_DIR", str(workspace))
+
+    with pytest.raises(RuntimeError, match="real directory"):
+        app_initializer.create_directories()
+
+
+def test_agent_workspace_is_inside_the_data_directory():
+    """It has to stay under data/ to be covered by the Docker bind mount,
+    so the guard cannot simply be 'anything under DATA_DIR is denied'."""
+    assert os.path.realpath(AGENT_WORKSPACE_DIR).startswith(
+        os.path.realpath(DATA_DIR) + os.sep
+    )
+
+
+# ── An active workspace ──────────────────────────────────────────────
+
+def test_workspace_bound_at_the_data_directory_still_blocks_app_state():
+    """vet_workspace() accepts the data directory, and chat_routes auto-binds
+    a workspace from a path named in the message, so this is reachable."""
+    with workspace_at(DATA_DIR):
+        with pytest.raises(ValueError, match="application state"):
+            _resolve_tool_path("sessions.json")
+
+
+def test_workspace_bound_above_the_data_directory_still_blocks_app_state():
+    with workspace_at(os.path.dirname(DATA_DIR)):
+        with pytest.raises(ValueError, match="application state"):
+            _resolve_tool_path(os.path.join(DATA_DIR, "sessions.json"))
+
+
+def test_workspace_bound_at_the_data_directory_refuses_the_empty_search_root():
+    """grep/glob/ls with no path take the workspace itself as the root, which
+    skipped the in-workspace resolver and enumerated the state directory."""
+    with workspace_at(DATA_DIR):
+        with pytest.raises(ValueError, match="application state"):
+            _resolve_search_root("")
+
+
+def test_vet_workspace_refuses_the_data_directory():
+    """Rejecting the bind is the cleaner failure: the client is told the
+    workspace was refused instead of every tool call erroring separately."""
+    assert vet_workspace(DATA_DIR) is None
+
+
+def test_vet_workspace_accepts_the_agent_workspace():
+    os.makedirs(AGENT_WORKSPACE_DIR, exist_ok=True)
+    assert vet_workspace(AGENT_WORKSPACE_DIR) == os.path.realpath(AGENT_WORKSPACE_DIR)
+
+
+def test_workspace_bound_at_the_data_directory_still_allows_the_agent_workspace():
+    with workspace_at(DATA_DIR):
+        resolved = _resolve_tool_path(os.path.join("agent_workspace", "notes.txt"))
+    assert resolved == os.path.realpath(os.path.join(AGENT_WORKSPACE_DIR, "notes.txt"))
+
+
+# ── An opt-in extra root ─────────────────────────────────────────────
+
+def test_extra_root_covering_the_data_directory_still_blocks_app_state(monkeypatch):
+    monkeypatch.setattr(
+        "src.settings.get_setting", lambda *_a, **_k: [os.path.dirname(DATA_DIR)]
+    )
+    with pytest.raises(ValueError, match="application state"):
+        _resolve_tool_path(os.path.join(DATA_DIR, "sessions.json"))
+
+
+# ── What the agent keeps ─────────────────────────────────────────────
+
+def test_allows_files_in_the_agent_workspace():
+    resolved = _resolve_tool_path(os.path.join(AGENT_WORKSPACE_DIR, "scratch.txt"))
+    assert resolved == os.path.realpath(os.path.join(AGENT_WORKSPACE_DIR, "scratch.txt"))
+
+
+@pytest.mark.parametrize("directory, why", [
+    (UPLOAD_DIR,
+     "_uploaded_files_context_message emits path= and tells the model to "
+     "read it with read_file (src/agent_loop.py)"),
+    (MAIL_ATTACHMENTS_DIR,
+     "download_attachment returns the path and its description says to read "
+     "it with read_file (mcp_servers/email_server.py)"),
+    (PERSONAL_DIR,
+     "GET /api/personal returns a path per file and is reachable through the "
+     "app_api tool, which does not block that prefix"),
+    (PERSONAL_UPLOADS_DIR,
+     "indexed into personal docs by routes/personal_routes.py, and listed as "
+     "an absolute path by manage_rag"),
+])
+def test_allows_user_content_the_app_hands_to_the_model(directory, why):
+    """Carving these out is not convenience. The app gives the model these
+    paths and tells it to read them, so denying them breaks the feature."""
+    target = os.path.join(directory, "example.txt")
+    assert _resolve_tool_path(target) == os.path.realpath(target), why
+
+
+def test_runbook_is_covered_by_the_personal_docs_carve_out():
+    """RUNBOOK_DIR nests under PERSONAL_DIR, so it needs no entry of its own."""
+    target = os.path.join(RUNBOOK_DIR, "notes.md")
+    assert _resolve_tool_path(target) == os.path.realpath(target)
+
+
+def test_allows_tmp():
+    """Unchanged: /tmp is still a root and holds no application state."""
+    assert _resolve_tool_path("/tmp/scratch.txt") == os.path.realpath("/tmp/scratch.txt")
+
+
+def test_subprocess_cwd_is_the_agent_workspace():
+    """bash/python cwd has to move with the file root, or the agent writes
+    where read_file can no longer look."""
+    assert agent_cwd() == os.path.realpath(AGENT_WORKSPACE_DIR)
+
+
+def test_sensitive_deny_list_still_fires_inside_the_agent_workspace():
+    """The new guard is layered on the existing one, not a replacement."""
+    with pytest.raises(ValueError, match="sensitive directory"):
+        _resolve_tool_path(os.path.join(AGENT_WORKSPACE_DIR, "id_rsa"))
+
+
+# ── Misconfigured carve-outs and recursive traversal ────────────────
+
+def _configure_test_data_tree(monkeypatch, data_dir):
+    current_constants = importlib.import_module("src.constants")
+    current_execution = importlib.import_module("src.tool_execution")
+    monkeypatch.setattr(current_constants, "DATA_DIR", str(data_dir), raising=False)
+    readable = {
+        "AGENT_WORKSPACE_DIR": data_dir / "agent_workspace",
+        "UPLOAD_DIR": data_dir / "uploads",
+        "MAIL_ATTACHMENTS_DIR": data_dir / "mail-attachments",
+        "PERSONAL_DIR": data_dir / "personal_docs",
+        "PERSONAL_UPLOADS_DIR": data_dir / "personal_uploads",
+    }
+    for name, path in readable.items():
+        monkeypatch.setattr(current_constants, name, str(path), raising=False)
+    monkeypatch.setattr(
+        current_execution,
+        "AGENT_WORKSPACE_DIR",
+        str(readable["AGENT_WORKSPACE_DIR"]),
+    )
+    return readable
+
+
+@contextmanager
+def current_workspace_at(path):
+    current_execution = importlib.import_module("src.tool_execution")
+    token = current_execution._active_workspace.set(os.path.realpath(path))
+    try:
+        yield
+    finally:
+        current_execution._active_workspace.reset(token)
+
+
+@pytest.mark.parametrize(
+    "bad_kind", ["equal", "ancestor", "root", "empty", "dot", "symlink"]
+)
+def test_invalid_readable_carveout_cannot_cancel_state_deny(
+    tmp_path, monkeypatch, bad_kind
+):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    bad = {
+        "equal": str(data_dir),
+        "ancestor": str(tmp_path),
+        "root": os.path.abspath(os.sep),
+        "empty": "",
+        "dot": ".",
+    }.get(bad_kind)
+    if bad_kind == "symlink":
+        link = tmp_path / "data-link"
+        try:
+            link.symlink_to(data_dir, target_is_directory=True)
+        except OSError:
+            pytest.skip("cannot create symlink")
+        bad = str(link)
+    current_execution = importlib.import_module("src.tool_execution")
+    monkeypatch.setattr(current_execution, "AGENT_WORKSPACE_DIR", bad)
+    secret = data_dir / "settings.json"
+    secret.write_text("STATE_SECRET\n", encoding="utf-8")
+
+    with pytest.raises(ValueError, match="application state"):
+        current_execution._resolve_tool_path(str(secret))
+    with pytest.raises(ValueError, match="default agent workspace"):
+        current_execution._resolve_search_root("")
+    assert os.path.realpath(readable["UPLOAD_DIR"]) in current_execution._tool_path_roots()
+
+
+def test_recursive_glob_and_grep_hide_state_but_keep_readable_descendants(
+    tmp_path, monkeypatch
+):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    workspace = readable["AGENT_WORKSPACE_DIR"]
+    workspace.mkdir()
+    (workspace / "notes.json").write_text("SHARED_MARKER readable\n", encoding="utf-8")
+    (data_dir / "settings.json").write_text("SHARED_MARKER secret\n", encoding="utf-8")
+
+    with current_workspace_at(tmp_path):
+        glob_result = asyncio.run(GlobTool().execute(
+            '{"pattern": "**/*.json", "path": ""}', {}
+        ))
+        grep_result = asyncio.run(GrepTool().execute(
+            '{"pattern": "SHARED_MARKER", "path": ""}', {}
+        ))
+
+    assert "notes.json" in glob_result["output"]
+    assert "settings.json" not in glob_result["output"]
+    assert "notes.json" in grep_result["output"]
+    assert "settings.json" not in grep_result["output"]
+
+
+def test_recursive_glob_and_grep_hide_state_from_extra_root(tmp_path, monkeypatch):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    readable["AGENT_WORKSPACE_DIR"].mkdir()
+    (readable["AGENT_WORKSPACE_DIR"] / "public.txt").write_text(
+        "TOKEN visible\n", encoding="utf-8"
+    )
+    (data_dir / "auth.json").write_text("TOKEN hidden\n", encoding="utf-8")
+    monkeypatch.setattr("src.settings.get_setting", lambda *_a, **_k: [str(tmp_path)])
+
+    glob_result = asyncio.run(GlobTool().execute(
+        f'{{"pattern": "**/*", "path": "{tmp_path}"}}', {}
+    ))
+    grep_result = asyncio.run(GrepTool().execute(
+        f'{{"pattern": "TOKEN", "path": "{tmp_path}"}}', {}
+    ))
+
+    assert "public.txt" in glob_result["output"]
+    assert "auth.json" not in glob_result["output"]
+    assert "public.txt" in grep_result["output"]
+    assert "auth.json" not in grep_result["output"]
+
+
+def test_existing_file_cannot_become_a_readable_directory_carveout(
+    tmp_path, monkeypatch
+):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    _configure_test_data_tree(monkeypatch, data_dir)
+    secret = data_dir / "auth.json"
+    secret.write_text("STATE_SECRET\n", encoding="utf-8")
+    current_constants = importlib.import_module("src.constants")
+    monkeypatch.setattr(current_constants, "UPLOAD_DIR", str(secret))
+    current_execution = importlib.import_module("src.tool_execution")
+
+    assert (
+        os.path.realpath(secret)
+        not in current_execution._agent_readable_data_subdirs()
+    )
+    with pytest.raises(ValueError, match="application state"):
+        current_execution._resolve_tool_path(str(secret))
+
+
+def test_external_mail_attachment_directory_remains_readable(tmp_path, monkeypatch):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    _configure_test_data_tree(monkeypatch, data_dir)
+    external = tmp_path / "external-mail"
+    external.mkdir()
+    attachment = external / "message.txt"
+    attachment.write_text("mail body\n", encoding="utf-8")
+    current_constants = importlib.import_module("src.constants")
+    monkeypatch.setattr(current_constants, "MAIL_ATTACHMENTS_DIR", str(external))
+    current_execution = importlib.import_module("src.tool_execution")
+
+    assert current_execution._resolve_tool_path(str(attachment)) == os.path.realpath(
+        attachment
+    )
+
+
+@pytest.mark.skipif(
+    os.path.normcase("DATA") == os.path.normcase("data"),
+    reason="requires a platform with case-sensitive path comparison",
+)
+def test_case_distinct_path_cannot_masquerade_as_readable_descendant(
+    tmp_path, monkeypatch
+):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    _configure_test_data_tree(monkeypatch, data_dir)
+    distinct = tmp_path / "DATA" / "agent_workspace"
+    distinct.mkdir(parents=True)
+    current_execution = importlib.import_module("src.tool_execution")
+    monkeypatch.setattr(current_execution, "AGENT_WORKSPACE_DIR", str(distinct))
+
+    assert (
+        os.path.realpath(distinct)
+        not in current_execution._agent_readable_data_subdirs()
+    )
+
+
+@pytest.mark.parametrize("use_workspace", [True, False])
+def test_ls_hides_protected_entries_when_root_contains_data(
+    tmp_path, monkeypatch, use_workspace
+):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    _configure_test_data_tree(monkeypatch, data_dir)
+    (tmp_path / "visible.txt").write_text("visible\n", encoding="utf-8")
+    secret = data_dir / "settings.json"
+    secret.write_text("SECRET_WITH_SIZE\n", encoding="utf-8")
+    if use_workspace:
+        context = current_workspace_at(tmp_path)
+        content = '{"path": ""}'
+    else:
+        monkeypatch.setattr("src.settings.get_setting", lambda *_a, **_k: [str(tmp_path)])
+        context = nullcontext()
+        content = f'{{"path": "{tmp_path}"}}'
+
+    with context:
+        result = asyncio.run(LsTool().execute(content, {}))
+
+    assert "visible.txt" in result["output"]
+    assert "settings.json" not in result["output"]
+    assert "SECRET_WITH_SIZE" not in result["output"]
+    assert "data/" not in result["output"]
+
+
+@pytest.mark.skipif(shutil.which("rg") is None, reason="requires ripgrep")
+def test_state_spanning_grep_bounds_dangerous_regex(tmp_path, monkeypatch):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    workspace = readable["AGENT_WORKSPACE_DIR"]
+    workspace.mkdir()
+    (workspace / "long.txt").write_text("a" * 250_000 + "!\n", encoding="utf-8")
+    (data_dir / "auth.txt").write_text("a" * 250_000 + "!\n", encoding="utf-8")
+
+    started = time.monotonic()
+    with current_workspace_at(tmp_path):
+        result = asyncio.run(GrepTool().execute(
+            '{"pattern": "(a+)+$", "path": "", "max_results": 1}', {}
+        ))
+    elapsed = time.monotonic() - started
+
+    assert result["exit_code"] == 0
+    assert "auth.txt" not in result["output"]
+    assert elapsed < 5
+
+
+def test_state_spanning_grep_stops_process_at_max_results(tmp_path, monkeypatch):
+    import subprocess
+
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    _configure_test_data_tree(monkeypatch, data_dir)
+    instances = []
+
+    class FakeProcess:
+        def __init__(self, *args, **kwargs):
+            self.stdout = iter(
+                f"{tmp_path}/visible-{index}.txt:1:MATCH\n" for index in range(100)
+            )
+            self.terminated = False
+            instances.append(self)
+
+        def poll(self):
+            return 0 if self.terminated else None
+
+        def terminate(self):
+            self.terminated = True
+
+        def wait(self, timeout=None):
+            return 0
+
+        def kill(self):
+            self.terminated = True
+
+    monkeypatch.setattr(shutil, "which", lambda _name: "/usr/bin/rg")
+    monkeypatch.setattr(subprocess, "Popen", FakeProcess)
+    with current_workspace_at(tmp_path):
+        result = asyncio.run(GrepTool().execute(
+            '{"pattern": "MATCH", "path": "", "max_results": 1}', {}
+        ))
+
+    assert len(instances) == 1
+    assert instances[0].terminated is True
+    assert result["output"].count(":1:MATCH") == 1
+
+
+@pytest.mark.skipif(shutil.which("rg") is None, reason="requires ripgrep")
+def test_state_spanning_grep_keeps_relative_glob_semantics(tmp_path, monkeypatch):
+    data_dir = tmp_path / "data"
+    data_dir.mkdir()
+    readable = _configure_test_data_tree(monkeypatch, data_dir)
+    nested = readable["AGENT_WORKSPACE_DIR"] / "nested"
+    nested.mkdir(parents=True)
+    (nested / "readable.py").write_text("PATH_GLOB_MARKER\n", encoding="utf-8")
+    (data_dir / "protected.py").write_text("PATH_GLOB_MARKER\n", encoding="utf-8")
+
+    with current_workspace_at(tmp_path):
+        result = asyncio.run(GrepTool().execute(
+            '{"pattern": "PATH_GLOB_MARKER", "path": "", "glob": "**/*.py"}',
+            {},
+        ))
+
+    assert "readable.py" in result["output"]
+    assert "protected.py" not in result["output"]

tests/test_code_nav_tools.py

@@ -91,6 +91,17 @@ def test_grep_python_fallback_when_no_rg(repo, monkeypatch):
     assert ".git/config" not in r["output"]
 
 
+def test_grep_python_fallback_uses_relative_glob_paths(repo, monkeypatch):
+    monkeypatch.setattr(shutil, "which", lambda name: None)
+    r = _run(
+        "grep",
+        f'{{"pattern": "needle|python", "glob": "**/*.py", "path": "{repo}"}}',
+    )
+    assert r["exit_code"] == 0
+    assert "a.py" in r["output"]
+    assert "sub/deep/c.py" in r["output"]
+
+
 @pytest.mark.skipif(shutil.which("rg") is None, reason="targets the ripgrep fast-path")
 def test_grep_skips_case_variant_sensitive_files_rg(repo):
     """The rg fast-path must exclude deny-listed key files case-insensitively.

tests/test_tool_path_confinement.py

@@ -161,12 +161,14 @@ def test_blocks_netrc():
         _resolve_tool_path("~/.netrc")
 
 
-def test_allows_project_data(tmp_path):
+def test_allows_agent_workspace(tmp_path):
-    """Paths under project data/ must resolve cleanly."""
+    """Paths under the agent's workspace in project data/ must resolve
+    cleanly. The rest of data/ is application state and is rejected;
+    tests/test_agent_state_dir_confinement.py covers that side."""
     from src.tool_execution import _resolve_tool_path
-    from src.constants import DATA_DIR
+    from src.constants import AGENT_WORKSPACE_DIR
-    target = os.path.join(DATA_DIR, "test-confinement-ok.txt")
+    target = os.path.join(AGENT_WORKSPACE_DIR, "test-confinement-ok.txt")
-    os.makedirs(DATA_DIR, exist_ok=True)
+    os.makedirs(AGENT_WORKSPACE_DIR, exist_ok=True)
     with open(target, "w") as f:
         f.write("ok")
     try: