minstall: Add more safety checks when unpickling installdata

When need to catch exceptions just like we do in coredata.load() to
print proper error message instead of backtrace when user mix meson
versions.

This happens frequently when user has a newer version of meson installed
in their HOME and then "sudo meson install" uses the system version of
meson.

mesonbuild/coredata.py

@@ -23,6 +23,7 @@ from .mesonlib import (
     MesonException, EnvironmentException, MachineChoice, PerMachine,
     PerMachineDefaultable, default_libdir, default_libexecdir,
     default_prefix, split_args, OptionKey, OptionType, stringlistify,
+    pickle_load
 )
 from .wrap import WrapMode
 import ast
@@ -1047,23 +1048,11 @@ def major_versions_differ(v1: str, v2: str) -> bool:
 
 def load(build_dir: str) -> CoreData:
     filename = os.path.join(build_dir, 'meson-private', 'coredata.dat')
-    load_fail_msg = f'Coredata file {filename!r} is corrupted. Try with a fresh build tree.'
-    try:
-        with open(filename, 'rb') as f:
-            obj = pickle.load(f)
-    except (pickle.UnpicklingError, EOFError):
-        raise MesonException(load_fail_msg)
-    except (TypeError, ModuleNotFoundError, AttributeError):
-        raise MesonException(
-            f"Coredata file {filename!r} references functions or classes that don't "
-            "exist. This probably means that it was generated with an old "
-            "version of meson.")
-    if not isinstance(obj, CoreData):
-        raise MesonException(load_fail_msg)
-    if major_versions_differ(obj.version, version):
-        raise MesonVersionMismatchException(obj.version, version)
+    obj = pickle_load(filename, 'Coredata', CoreData)
+    assert isinstance(obj, CoreData), 'for mypy'
     return obj
 
+
 def save(obj: CoreData, build_dir: str) -> str:
     filename = os.path.join(build_dir, 'meson-private', 'coredata.dat')
     prev_filename = filename + '.prev'

mesonbuild/mesonlib/universal.py

@@ -31,6 +31,7 @@ import typing as T
 import uuid
 import textwrap
 import copy
+import pickle
 
 from mesonbuild import mlog
 
@@ -123,6 +124,7 @@ __all__ = [
     'listify',
     'partition',
     'path_is_in_root',
+    'pickle_load',
     'Popen_safe',
     'quiet_git',
     'quote_arg',
@@ -2232,3 +2234,23 @@ class OptionKey:
     def is_base(self) -> bool:
         """Convenience method to check if this is a base option."""
         return self.type is OptionType.BASE
+
+def pickle_load(filename: str, object_name: str, object_type: T.Type) -> T.Any:
+    load_fail_msg = f'{object_name} file {filename!r} is corrupted. Try with a fresh build tree.'
+    try:
+        with open(filename, 'rb') as f:
+            obj = pickle.load(f)
+    except (pickle.UnpicklingError, EOFError):
+        raise MesonException(load_fail_msg)
+    except (TypeError, ModuleNotFoundError, AttributeError):
+        raise MesonException(
+            f"{object_name} file {filename!r} references functions or classes that don't "
+            "exist. This probably means that it was generated with an old "
+            "version of meson.")
+    if not isinstance(obj, object_type):
+        raise MesonException(load_fail_msg)
+    from ..coredata import version as coredata_version
+    from ..coredata import major_versions_differ, MesonVersionMismatchException
+    if major_versions_differ(obj.version, coredata_version):
+        raise MesonVersionMismatchException(obj.version, coredata_version)
+    return obj

mesonbuild/minstall.py

@@ -18,7 +18,6 @@ from pathlib import Path
 import argparse
 import errno
 import os
-import pickle
 import shlex
 import shutil
 import subprocess
@@ -28,9 +27,7 @@ import typing as T
 from . import build
 from . import environment
 from .backend.backends import InstallData
-from .coredata import major_versions_differ, MesonVersionMismatchException
-from .coredata import version as coredata_version
-from .mesonlib import MesonException, Popen_safe, RealPathAction, is_windows, setup_vsenv
+from .mesonlib import MesonException, Popen_safe, RealPathAction, is_windows, setup_vsenv, pickle_load
 from .scripts import depfixer, destdir_join
 from .scripts.meson_exe import run_exe
 try:
@@ -133,13 +130,9 @@ class DirMaker:
 
 
 def load_install_data(fname: str) -> InstallData:
-    with open(fname, 'rb') as ifile:
-        obj = pickle.load(ifile)
-        if not isinstance(obj, InstallData) or not hasattr(obj, 'version'):
-            raise MesonVersionMismatchException('<unknown>', coredata_version)
-        if major_versions_differ(obj.version, coredata_version):
-            raise MesonVersionMismatchException(obj.version, coredata_version)
-        return obj
+    obj = pickle_load(fname, 'InstallData', InstallData)
+    assert isinstance(obj, InstallData), 'fo mypy'
+    return obj
 
 def is_executable(path: str, follow_symlinks: bool = False) -> bool:
     '''Checks whether any of the "x" bits are set in the source file mode.'''