I am getting a buffer overflow while using my webapp deployed to Apache2, mod_jk1.2 and Tomcat5.5.17.
I am basically trying to send an HTTP response back to the browser with a custom json header (X-JSON header) containing more than 8Kb since this is the default way to send json state back to the browser using Prototype.js. My basic question is this: is there a hard-coded limit of 8Kb for HTTP response headers? If the answer is yes I could see this being a serious problem in a world of AJAX where we not only want to send a XHTML snipped back to the browser in the entity body, but also piggyback additional state in the response. I browsed the source code for Tomcat5.5.17 and found out that AJP13 sends 8Kb packets back to apachelib-mod_jk. For the response entity body any number of 8Kb packets are sent, but for the response entity header it seems that always only one 8Kb packet is sent. I also found a post to this mailing list that although asked a similar question, did end up providing a definite answer aside from how to better log the problem (http://www.mail-archive.com/tomcat-dev@jakarta.apache.org/msg73387.html). And this is the exception I am seeing: -------------------------------------------------------------------------------------- Jan 4, 2007 9:08:11 PM org.apache.jk.common.MsgAjp cpBytes SEVERE: Buffer overflow: buffer.len=8192 pos=25 data=215738 Jan 4, 2007 9:08:11 PM org.apache.jk.common.MsgAjp cpBytes SEVERE: Overflow java.lang.Throwable at org.apache.jk.common.MsgAjp.cpBytes(MsgAjp.java:172) at org.apache.jk.common.MsgAjp.appendByteChunk(MsgAjp.java:146) at org.apache.jk.common.MsgAjp.appendBytes(MsgAjp.java:132) at org.apache.jk.common.JkInputStream.appendHead(JkInputStream.java:302) at org.apache.jk.core.MsgContext.action(MsgContext.java:258) at org.apache.coyote.Response.action(Response.java:182) at org.apache.coyote.Response.sendHeaders(Response.java:378) at org.apache.jk.common.JkInputStream.doWrite(JkInputStream.java:126) at org.apache.coyote.Response.doWrite(Response.java:559) at org.apache.catalina.connector.OutputBuffer.realWriteBytes(OutputBuffer.java:361) at org.apache.tomcat.util.buf.ByteChunk.flushBuffer(ByteChunk.java:433) at org.apache.catalina.connector.OutputBuffer.doFlush(OutputBuffer.java:314) at org.apache.catalina.connector.OutputBuffer.close(OutputBuffer.java:278) at org.apache.catalina.connector.Response.finishResponse(Response.java:476) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151) at org.apache.jk.server.JkCoyoteHandler.invoke(JkCoyoteHandler.java:199) at org.apache.jk.common.HandlerRequest.invoke(HandlerRequest.java:282) at org.apache.jk.common.ChannelSocket.invoke(ChannelSocket.java:754) at org.apache.jk.common.ChannelSocket.processConnection(ChannelSocket.java:684) at org.apache.jk.common.ChannelSocket$SocketConnection.runIt(ChannelSocket.java:876) at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684) at java.lang.Thread.run(Thread.java:595) -------------------------------------------------------------------------------------- thanks, -- yuri --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
