From 10bf4a6d5b651141171e648fde1b0ba25a87d37d Mon Sep 17 00:00:00 2001 From: Moonchild Date: Wed, 21 Oct 2020 23:48:32 +0000 Subject: [DOM Fetch] Detect broken pipes and propagate that write error to the caller. --- dom/fetch/FetchDriver.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'dom/fetch/FetchDriver.cpp') diff --git a/dom/fetch/FetchDriver.cpp b/dom/fetch/FetchDriver.cpp index d028ffdba..14c000121 100644 --- a/dom/fetch/FetchDriver.cpp +++ b/dom/fetch/FetchDriver.cpp @@ -772,6 +772,17 @@ FetchDriver::OnDataAvailable(nsIRequest* aRequest, nsresult rv = aInputStream->ReadSegments(NS_CopySegmentToStream, mPipeOutputStream, aCount, &aRead); + + // If no data was read, it's possible the output stream is closed but the + // ReadSegments call followed its contract of returning NS_OK despite write + // errors. Unfortunately, nsIOutputStream has an ill-conceived contract when + // taken together with ReadSegments' contract, because the pipe will just + // NS_OK if we try and invoke its Write* functions ourselves with a 0 count. + // So we must just assume the pipe is broken. + if (aRead == 0 && aCount != 0) { + return NS_BASE_STREAM_CLOSED; + } + return rv; } -- cgit v1.2.3