[ http://issues.apache.org/jira/browse/HTTPCORE-3?page=comments#action_12402422 ]
Oleg Kalnichevski commented on HTTPCORE-3: ------------------------------------------ Gordon, This issue has indeed been fixed in HttpCore, which is now a separate module within the HttpComponents project. HttpCore provides low level HTTP components that will form the foundation for HttpClient 4.0. See for details: http://jakarta.apache.org/httpcomponents/index.html http://jakarta.apache.org/httpcomponents/http-core/index.html HttpCore allows an alternative implementation of HttpDataReceiver be plugged in when dealing with target servers that are expected to produce malformed HTTP responses. Feel free to review the code and let us know if the problem has been solved in a satisfactory manner. Oleg > HttpParser triggers unfriendly OutOfMemoryError on challenging input > -------------------------------------------------------------------- > > Key: HTTPCORE-3 > URL: http://issues.apache.org/jira/browse/HTTPCORE-3 > Project: Jakarta HttpCore > Type: Bug > Components: HttpCore > Reporter: Gordon Mohr > > Many users of HttpClient use it to connect to servers which generate > challenging HTTP responses, such as responses which include an arbitrarily > large number of headers or headers of arbitrarily large size. (Sometimes such > headers are conformant with the spec, in that they contain legal characters > in plausible header formats; other times these are filled with binary content > that is a violation of the relevant specs. Even when technically legal, often > such giant headers are the inadvertent result of server-side bugs.) > As a Java execution environment always has a hard cap on the available heap > space, any parsing code which can use an arbitrary amount of memory risks > triggering an OutOfMemoryError, either in its own thread or even another > thread that happens to need memory after the parsing thread has exhausted it > all. > Such OutOfMemoryErrors are a particularly unfriendly way to indicate that a > practical limit has been exceeded, compared to other options. They can hide > the thread of execution which is most to blame. It is hard and awkward to set > up handlers that catch and recover from OOMEs wherever they are most likely > to occur. Even with such handlers, the actual allocation triggering an OOME > may occur in another critical thread, even if that thread has minimal and > well-controlled memory needs. > HttpClient ought to provide one or more ways for a user to protect against > such OOMEs, and instead receive a more convenient/recoverable indication of > an HTTP response that is impossible to process with the HttpClient library > within the available resources. Many approaches are possible; the easiest > would be to allow a user of HttpClient to set their own optional, pragmatic > limits on header sizes and number. Then, just as a user may already cleanly > cancel the stream-reading of an arbitrarily-long content-body without fouling > up their application state, they would be able to cancel the parsing of > oversized response headers. > Similar issues have been discussed before, for example in Bugzilla bug #25468 > (http://issues.apache.org/bugzilla/show_bug.cgi?id=25468) which was to > "Provide HttpParser plug-in mechanism." Though that issue is marked > resolved/fixed, there is no such plug-in mechanism allowing an OOME > workaround in the 3.x HttpClient, and it is not clear that a > mechanism/work-around exists in whatever 4.0 work has been completed. > So my suggestion is that this new issue be used to uniquely track the OOME > risk in HttpParser, and only be considered "fixed" when some version of > HttpClient offers an alternative to throwing OOMEs as a way of dealing with > challenging HTTP responses. Alternatively, this could simply become the issue > in the new system for collecting user-contributed workarounds/patches. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
