CVE-2007-4559 Patch

src/python/gem5/resources/downloader.py

@@ -501,5 +501,24 @@ def get_resource(
             )
             unpack_to = download_dest[: -len(tar_extension)]
             with tarfile.open(download_dest) as f:
-                f.extractall(unpack_to)
+                def is_within_directory(directory, target):
+
+                    abs_directory = os.path.abspath(directory)
+                    abs_target = os.path.abspath(target)
+
+                    prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                    return prefix == abs_directory
+
+                def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                    for member in tar.getmembers():
+                        member_path = os.path.join(path, member.name)
+                        if not is_within_directory(path, member_path):
+                            raise Exception("Attempted Path Traversal in Tar File")
+
+                    tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+                safe_extract(f, unpack_to)
             os.remove(download_dest)

tests/gem5/fixture.py

@@ -357,7 +357,26 @@ def _extract(self):
         import tarfile
 
         with tarfile.open(self.filename) as tf:
-            tf.extractall(self.path)
+            def is_within_directory(directory, target):
+
+                abs_directory = os.path.abspath(directory)
+                abs_target = os.path.abspath(target)
+
+                prefix = os.path.commonprefix([abs_directory, abs_target])
+
+                return prefix == abs_directory
+
+            def safe_extract(tar, path=".", members=None, *, numeric_owner=False):
+
+                for member in tar.getmembers():
+                    member_path = os.path.join(path, member.name)
+                    if not is_within_directory(path, member_path):
+                        raise Exception("Attempted Path Traversal in Tar File")
+
+                tar.extractall(path, members, numeric_owner=numeric_owner) 
+
+
+            safe_extract(tf, self.path)
 
     def _setup(self, testitem):
         # Check to see if there is a file downloaded