This is an automated email from the ASF dual-hosted git repository. markt pushed a commit to branch main in repository https://gitbox.apache.org/repos/asf/tomcat.git
The following commit(s) were added to refs/heads/main by this push: new 2538f6d Fix problems with file uploads and HTTP/2 2538f6d is described below commit 2538f6d74949751901afc5e04014ede4f867152a Author: Mark Thomas <ma...@apache.org> AuthorDate: Mon Jun 14 21:15:30 2021 +0100 Fix problems with file uploads and HTTP/2 Small writes from the user agent were triggering small window updates which in turn triggered more small writes. With lots of small writes the overhead protection code was activated and the connection closed. --- .../coyote/http2/Http2AsyncUpgradeHandler.java | 30 ++++++++++++------- .../apache/coyote/http2/Http2UpgradeHandler.java | 34 +++++++++++++++------- .../apache/coyote/http2/LocalStrings.properties | 2 ++ java/org/apache/coyote/http2/Stream.java | 24 +++++++++++++++ webapps/docs/changelog.xml | 10 +++++++ 5 files changed, 79 insertions(+), 21 deletions(-) diff --git a/java/org/apache/coyote/http2/Http2AsyncUpgradeHandler.java b/java/org/apache/coyote/http2/Http2AsyncUpgradeHandler.java index b77fee6..6d7e3eb 100644 --- a/java/org/apache/coyote/http2/Http2AsyncUpgradeHandler.java +++ b/java/org/apache/coyote/http2/Http2AsyncUpgradeHandler.java @@ -231,22 +231,32 @@ public class Http2AsyncUpgradeHandler extends Http2UpgradeHandler { @Override void writeWindowUpdate(AbstractNonZeroStream stream, int increment, boolean applicationInitiated) throws IOException { + if (log.isDebugEnabled()) { + log.debug(sm.getString("upgradeHandler.windowUpdateConnection", + getConnectionId(), Integer.valueOf(increment))); + } // Build window update frame for stream 0 byte[] frame = new byte[13]; ByteUtil.setThreeBytes(frame, 0, 4); frame[3] = FrameType.WINDOW_UPDATE.getIdByte(); ByteUtil.set31Bits(frame, 9, increment); // No need to send update from closed stream - if (stream instanceof Stream && ((Stream) stream).canWrite()) { - // Change stream Id - byte[] frame2 = new byte[13]; - ByteUtil.setThreeBytes(frame2, 0, 4); - frame2[3] = FrameType.WINDOW_UPDATE.getIdByte(); - ByteUtil.set31Bits(frame2, 9, increment); - ByteUtil.set31Bits(frame2, 5, stream.getIdAsInt()); - socketWrapper.write(BlockingMode.SEMI_BLOCK, protocol.getWriteTimeout(), - TimeUnit.MILLISECONDS, null, SocketWrapperBase.COMPLETE_WRITE, errorCompletion, - ByteBuffer.wrap(frame), ByteBuffer.wrap(frame2)); + if (stream instanceof Stream && ((Stream) stream).canWrite()) { + int streamIncrement = ((Stream) stream).getWindowUpdateSizeToWrite(increment); + if (streamIncrement > 0) { + if (log.isDebugEnabled()) { + log.debug(sm.getString("upgradeHandler.windowUpdateStream", + getConnectionId(), getIdAsString(), Integer.valueOf(streamIncrement))); + } + byte[] frame2 = new byte[13]; + ByteUtil.setThreeBytes(frame2, 0, 4); + frame2[3] = FrameType.WINDOW_UPDATE.getIdByte(); + ByteUtil.set31Bits(frame2, 9, streamIncrement); + ByteUtil.set31Bits(frame2, 5, stream.getIdAsInt()); + socketWrapper.write(BlockingMode.SEMI_BLOCK, protocol.getWriteTimeout(), + TimeUnit.MILLISECONDS, null, SocketWrapperBase.COMPLETE_WRITE, errorCompletion, + ByteBuffer.wrap(frame), ByteBuffer.wrap(frame2)); + } } else { socketWrapper.write(BlockingMode.SEMI_BLOCK, protocol.getWriteTimeout(), TimeUnit.MILLISECONDS, null, SocketWrapperBase.COMPLETE_WRITE, errorCompletion, diff --git a/java/org/apache/coyote/http2/Http2UpgradeHandler.java b/java/org/apache/coyote/http2/Http2UpgradeHandler.java index 994a7cb..fa650b7 100644 --- a/java/org/apache/coyote/http2/Http2UpgradeHandler.java +++ b/java/org/apache/coyote/http2/Http2UpgradeHandler.java @@ -804,6 +804,10 @@ class Http2UpgradeHandler extends AbstractStream implements InternalHttpUpgradeH */ void writeWindowUpdate(AbstractNonZeroStream stream, int increment, boolean applicationInitiated) throws IOException { + if (log.isDebugEnabled()) { + log.debug(sm.getString("upgradeHandler.windowUpdateConnection", + getConnectionId(), Integer.valueOf(increment))); + } synchronized (socketWrapper) { // Build window update frame for stream 0 byte[] frame = new byte[13]; @@ -812,17 +816,25 @@ class Http2UpgradeHandler extends AbstractStream implements InternalHttpUpgradeH ByteUtil.set31Bits(frame, 9, increment); socketWrapper.write(true, frame, 0, frame.length); // No need to send update from closed stream - if (stream instanceof Stream && ((Stream) stream).canWrite()) { - // Change stream Id and re-use - ByteUtil.set31Bits(frame, 5, stream.getIdAsInt()); - try { - socketWrapper.write(true, frame, 0, frame.length); - socketWrapper.flush(true); - } catch (IOException ioe) { - if (applicationInitiated) { - handleAppInitiatedIOException(ioe); - } else { - throw ioe; + if (stream instanceof Stream && ((Stream) stream).canWrite()) { + int streamIncrement = ((Stream) stream).getWindowUpdateSizeToWrite(increment); + if (streamIncrement > 0) { + if (log.isDebugEnabled()) { + log.debug(sm.getString("upgradeHandler.windowUpdateStream", + getConnectionId(), getIdAsString(), Integer.valueOf(streamIncrement))); + } + // Re-use buffer as connection update has already been written + ByteUtil.set31Bits(frame, 5, stream.getIdAsInt()); + ByteUtil.set31Bits(frame, 9, streamIncrement); + try { + socketWrapper.write(true, frame, 0, frame.length); + socketWrapper.flush(true); + } catch (IOException ioe) { + if (applicationInitiated) { + handleAppInitiatedIOException(ioe); + } else { + throw ioe; + } } } } else { diff --git a/java/org/apache/coyote/http2/LocalStrings.properties b/java/org/apache/coyote/http2/LocalStrings.properties index 3e114d8..25858cb 100644 --- a/java/org/apache/coyote/http2/LocalStrings.properties +++ b/java/org/apache/coyote/http2/LocalStrings.properties @@ -158,6 +158,8 @@ upgradeHandler.upgradeDispatch.entry=Entry, Connection [{0}], SocketStatus [{1}] upgradeHandler.upgradeDispatch.exit=Exit, Connection [{0}], SocketState [{1}] upgradeHandler.windowSizeReservationInterrupted=Connection [{0}], Stream [{1}], reservation for [{2}] bytes upgradeHandler.windowSizeTooBig=Connection [{0}], Stream [{1}], Window size too big +upgradeHandler.windowUpdateConnection=Connection [{0}], Sent window update to client increasing window by [{1}] bytes +upgradeHandler.windowUpdateStream=Connection [{0}], Stream [{1}], Sent window update to client increasing window by [{2}] bytes upgradeHandler.writeBody=Connection [{0}], Stream [{1}], Data length [{2}], EndOfStream [{3}] upgradeHandler.writeHeaders=Connection [{0}], Stream [{1}], Writing the headers, EndOfStream [{2}] upgradeHandler.writePushHeaders=Connection [{0}], Stream [{1}], Pushed stream [{2}], EndOfStream [{3}] diff --git a/java/org/apache/coyote/http2/Stream.java b/java/org/apache/coyote/http2/Stream.java index 28ec14e..8d93d98 100644 --- a/java/org/apache/coyote/http2/Stream.java +++ b/java/org/apache/coyote/http2/Stream.java @@ -82,6 +82,9 @@ class Stream extends AbstractNonZeroStream implements HeaderEmitter { private volatile StringBuilder cookieHeader = null; + private Object pendingWindowUpdateForStreamLock = new Object(); + private int pendingWindowUpdateForStream = 0; + Stream(Integer identifier, Http2UpgradeHandler handler) { this(identifier, handler, null); @@ -744,6 +747,27 @@ class Stream extends AbstractNonZeroStream implements HeaderEmitter { } + int getWindowUpdateSizeToWrite(int increment) { + int result; + int threshold = handler.getProtocol().getOverheadWindowUpdateThreshold(); + synchronized (pendingWindowUpdateForStreamLock) { + if (increment > threshold) { + result = increment + pendingWindowUpdateForStream; + pendingWindowUpdateForStream = 0; + } else { + pendingWindowUpdateForStream += increment; + if (pendingWindowUpdateForStream > threshold) { + result = pendingWindowUpdateForStream; + pendingWindowUpdateForStream = 0; + } else { + result = 0; + } + } + } + return result; + } + + private static void push(final Http2UpgradeHandler handler, final Request request, final Stream stream) throws IOException { if (org.apache.coyote.Constants.IS_SECURITY_ENABLED) { diff --git a/webapps/docs/changelog.xml b/webapps/docs/changelog.xml index 41ebbd0..c5dc156 100644 --- a/webapps/docs/changelog.xml +++ b/webapps/docs/changelog.xml @@ -112,6 +112,16 @@ connections. Treat them the same way as clean closes of non-TLS connections rather than as unknown errors. (markt) </fix> + <fix> + Modify the HTTP/2 connector not to sent small updates for stream flow + control windows to the user agent as, depending on how the user agent is + written, this may trigger small writes from the user agent that in turn + trigger the overhead protection. Small updates for stream flow control + windows are now combined with subsequent flow control window updates for + that stream to ensure that all stream flow control window updates sent + from Tomcat are larger than <code>overheadWindowUpdateThreshold</code>. + (markt) + </fix> </changelog> </subsection> <subsection name="Other"> --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@tomcat.apache.org For additional commands, e-mail: dev-h...@tomcat.apache.org