Trap the decoding AssertionError in all codepaths

diff --git a/loader/lib/parser.py b/loader/lib/parser.py
index 8c98076f5467c8800151c20e057f0756c9a25a3b..b97c8b338bba8c0b86792ad06d7aa1747d416f55 100644 (file)
--- a/loader/lib/parser.py
+++ b/loader/lib/parser.py
@@ -310,8 +310,15 @@ class ArchivesParser(object):
                                return
                        # For now, accept anything not text/plain
                        if container.get_content_type() != 'text/plain':
-                               self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                               try:
+                                       self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                               except AssertionError:
+                                       # Badly encoded data can throw an exception here, where the python
+                                       # libraries fail to handle it and enters a cannot-happen path.
+                                       # In which case we just ignore this attachment.
+                                       return
                                return
+
                        # It's a text/plain, it might be worthwhile.
                        # If it has a name, we consider it an attachments
                        if not container.get_params():
@@ -319,19 +326,42 @@ class ArchivesParser(object):
                        for k,v in container.get_params():
                                if k=='name' and v != '':
                                        # Yes, it has a name
-                                       self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                                       try:
+                                               self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                                       except AssertionError:
+                                               # Badly encoded data can throw an exception here, where the python
+                                               # libraries fail to handle it and enters a cannot-happen path.
+                                               # In which case we just ignore this attachment.
+                                               return
+
                                        return
+
                        # If it's content-disposition=attachment, we also want to save it
                        if 'Content-Disposition' in container and container['Content-Disposition'].startswith('attachment'):
-                               self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                               try:
+                                       self.attachments.append((self._extract_filename(container), container.get_content_type(), container.get_payload(decode=True)))
+                               except AssertionError:
+                                       # Badly encoded data can throw an exception here, where the python
+                                       # libraries fail to handle it and enters a cannot-happen path.
+                                       # In which case we just ignore this attachment.
+                                       return
+
                                return
+
                        # If we have already found one text/plain part, make all
                        # further text/plain parts attachments
                        if self.attachments_found_first_plaintext:
                                # However, this will also *always* catch the MIME part added
                                # by majordomo with the footer. So if that one is present,
                                # we need to explicitly exclude it again.
-                               b = container.get_payload(decode=True)
+                               try:
+                                       b = container.get_payload(decode=True)
+                               except AssertionError:
+                                       # Badly encoded data can throw an exception here, where the python
+                                       # libraries fail to handle it and enters a cannot-happen path.
+                                       # In which case we just ignore this attachment.
+                                       return
+
                                if isinstance(b, str) and not self._re_footer.match(b):
                                        # We know there is no name for this one
                                        self.attachments.append((None, container.get_content_type(), b))