Patches item #900744, was opened at 2004-02-19 23:14 Message generated for change (Comment added) made by gbrandl You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=900744&group_id=5470
Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: Library (Lib) Group: Python 2.5 Status: Open Resolution: Accepted Priority: 5 Private: No Submitted By: Wummel (calvin) Assigned to: Georg Brandl (gbrandl) Summary: catch invalid chunk length in httplib read routine Initial Comment: In HTTPResponse._read_chunked the chunk length is not checked to be a valid integer, and a ValueError will be raised in such a case. The attached patch catches ValueError (which should not normally happen, so this try:except: is reasonably fast), and raises IncompleteRead exception instead. I have no test case for this yet, but am trying to construct one :) ---------------------------------------------------------------------- >Comment By: Georg Brandl (gbrandl) Date: 2007-02-19 12:10 Message: Logged In: YES user_id=849994 Originator: NO Martin: which patch? Mine, which returns what was read so far, or calvin's, which raises IncompleteRead? ---------------------------------------------------------------------- Comment By: Martin v. Löwis (loewis) Date: 2007-02-18 08:39 Message: Logged In: YES user_id=21627 Originator: NO Georg, the patch is fine for 2.6, please apply (for 2.5, I would be cautious because of the behaviour change). ---------------------------------------------------------------------- Comment By: Wummel (calvin) Date: 2006-02-01 22:16 Message: Logged In: YES user_id=9205 I attached a simple testcase that triggers the bug. IMHO this patch should be applied for Python 2.5. ---------------------------------------------------------------------- Comment By: Raymond Hettinger (rhettinger) Date: 2005-07-19 01:07 Message: Logged In: YES user_id=80475 Technically, the patch is fine and it is the way the code should have been written in the first place. Please bring-up on python-dev to determine whether it should be done. I can imagine that a fair amount of existing code has through trial and error discovered the ValueError and chosen to catch that. Changing the exception may unnecessarily break people's code. Sometimes we take that step when it needs to be done, but there should be a good pay-off and, in this case, I don't see it. You may also want to mention it on comp.lang.python to see if anyone cares If the patch goes forward, see if you can mock-up a test that triggers the exception so we have a good unittest. In anycase, this should not be backported (we avoid giving people reasons to not upgrade). ---------------------------------------------------------------------- Comment By: Georg Brandl (birkenfeld) Date: 2005-07-18 19:34 Message: Logged In: YES user_id=1188172 Attaching patch which does what agwego said (httplib-chunked.diff). Please review. ---------------------------------------------------------------------- Comment By: agwego (agwego) Date: 2005-02-28 16:53 Message: Logged In: YES user_id=1228982 I've run into this problem in conjunction with mod_python 3.1.4 (and although the problem is caused in mod_python) my python skills aren't up to the task. Which leaves me with fixing httplib. Although the above patch works when it comes to end of file situations, I think it would be better to return what has been consumed so far and leave it at that. A few lines down there's a comment about consuming trailers, this is the case that is tripping up httplib as far as I can tell. This is happening in Python 2.3.4. --- packages/Python-2.3.4/Lib/httplib.py Sun Nov 2 11:51:38 2003 +++ httplib.py Mon Feb 28 11:26:48 2005 @@ -423,7 +423,11 @@ i = line.find(';') if i >= 0: line = line[:i] # strip chunk-extensions - chunk_left = int(line, 16) + try: + chunk_left = int(line, 16) + except ValueError, msg: + self.close() + return value if chunk_left == 0: break if amt is None: ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=305470&aid=900744&group_id=5470 _______________________________________________ Patches mailing list Patches@python.org http://mail.python.org/mailman/listinfo/patches