Correctly handle newline detection not only for open boundary but for…

… close mark too (#3758)
aio-libs · May 13, 2019 · 7531fee · 7531fee
1 parent 0ad5d90
commit 7531fee
Showing 1 changed file with 10 additions and 3 deletions.
diff --git a/aiohttp/multipart.py b/aiohttp/multipart.py
@@ -647,15 +647,22 @@ async def _read_until_first_boundary(self) -> None:
             if chunk == b'':
                 raise ValueError("Could not find starting boundary %r"
                                  % (self._boundary))
-            if chunk.startswith(self._boundary):
+            newline = None
+            end_boundary = self._boundary + b'--'
+            if chunk.startswith(end_boundary):
+                _, newline = chunk.split(end_boundary, 1)
+            elif chunk.startswith(self._boundary):
                 _, newline = chunk.split(self._boundary, 1)
-                assert newline in (b'\r\n', b'\n')
+            if newline is not None:
+                assert newline in (b'\r\n', b'\n'), (newline,
+                                                     chunk,
+                                                     self._boundary)
                 self._newline = newline
 
             chunk = chunk.rstrip()
             if chunk == self._boundary:
                 return
-            elif chunk == self._boundary + b'--':
+            elif chunk == end_boundary:
                 self._at_eof = True
                 return