1676543 - Assertion failure: aPresContext->UsesExChUnits(), at src/layout/style/nsFontFaceUtils.cpp:56

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect)

Description

[Tyson Smith [:tsmith]]

Attachment: testcase.html

Fuzzers have been hitting this since 20200911-941862090875

Assertion failure: aPresContext->UsesExChUnits(), at src/layout/style/nsFontFaceUtils.cpp:56

#0 0x7f1b16ac3058 in StyleFontUsage(mozilla::ComputedStyle*, nsPresContext*, gfxUserFontSet const*, gfxUserFontEntry const*, nsTSubstring<char16_t> const&) src/layout/style/nsFontFaceUtils.cpp:56:5
#1 0x7f1b16aac65c in FrameFontUsage src/layout/style/nsFontFaceUtils.cpp:70:7
#2 0x7f1b16aac65c in nsFontFaceUtils::MarkDirtyForFontChange(nsIFrame*, gfxUserFontEntry const*) src/layout/style/nsFontFaceUtils.cpp:161:28
#3 0x7f1b16aa92c6 in nsFontFaceLoader::FontLoadComplete() src/layout/style/nsFontFaceLoader.cpp:299:12
#4 0x7f1b16aa947c in non-virtual thunk to nsFontFaceLoader::FontLoadComplete() src/layout/style/nsFontFaceLoader.cpp
#5 0x7f1b16aa8f65 in nsFontFaceLoader::OnStreamComplete(nsIStreamLoader*, nsISupports*, nsresult, unsigned int, unsigned char const*) src/layout/style/nsFontFaceLoader.cpp:279:19
#6 0x7f1b124a2f22 in mozilla::net::nsStreamLoader::OnStopRequest(nsIRequest*, nsresult) src/netwerk/base/nsStreamLoader.cpp:89:20
#7 0x7f1b12907911 in nsCORSListenerProxy::OnStopRequest(nsIRequest*, nsresult) src/netwerk/protocol/http/nsCORSListenerProxy.cpp:614:27
#8 0x7f1b1286fc38 in mozilla::net::HttpChannelChild::DoOnStopRequest(nsIRequest*, nsresult, nsISupports*) src/netwerk/protocol/http/HttpChannelChild.cpp:1008:15
#9 0x7f1b1286f601 in mozilla::net::HttpChannelChild::OnStopRequest(nsresult const&, mozilla::net::ResourceTimingStructArgs const&, mozilla::net::nsHttpHeaderArray const&) src/netwerk/protocol/http/HttpChannelChild.cpp:887:5
#10 0x7f1b128ce84d in operator() src/netwerk/protocol/http/HttpChannelChild.cpp:781:15
#11 0x7f1b128ce84d in std::_Function_handler<void (), mozilla::net::HttpChannelChild::ProcessOnStopRequest(nsresult const&, mozilla::net::ResourceTimingStructArgs const&, mozilla::net::nsHttpHeaderArray const&, nsTArray<mozilla::net::ConsoleReportCollected>&&, bool)::$_9>::_M_invoke(std::_Any_data const&) /builds/worker/fetches/clang/bin/../lib/gcc/x86_64-unknown-linux-gnu/7.4.0/../../../../include/c++/7.4.0/bits/std_function.h:316:2
#12 0x7f1b12a335db in mozilla::net::ChannelEventQueue::FlushQueue() src/netwerk/ipc/ChannelEventQueue.cpp:90:12
#13 0x7f1b12a67f89 in MaybeFlushQueue /builds/worker/workspace/obj-build/dist/include/mozilla/net/ChannelEventQueue.h:330:5
#14 0x7f1b12a67f89 in CompleteResume /builds/worker/workspace/obj-build/dist/include/mozilla/net/ChannelEventQueue.h:309:5
#15 0x7f1b12a67f89 in mozilla::net::ChannelEventQueue::ResumeInternal()::CompleteResumeRunnable::Run() src/netwerk/ipc/ChannelEventQueue.cpp:148:17
#16 0x7f1b122af8d2 in mozilla::SchedulerGroup::Runnable::Run() src/xpcom/threads/SchedulerGroup.cpp:146:20
#17 0x7f1b122b58ef in mozilla::RunnableTask::Run() src/xpcom/threads/TaskController.cpp:450:16
#18 0x7f1b122b3f5a in mozilla::TaskController::DoExecuteNextTaskOnlyMainThreadInternal(mozilla::detail::BaseAutoLock<mozilla::Mutex&> const&) src/xpcom/threads/TaskController.cpp:720:26
#19 0x7f1b122b3004 in mozilla::TaskController::ExecuteNextTaskOnlyMainThreadInternal(mozilla::detail::BaseAutoLock<mozilla::Mutex&> const&) src/xpcom/threads/TaskController.cpp:579:15
#20 0x7f1b122b31b7 in mozilla::TaskController::ProcessPendingMTTask(bool) src/xpcom/threads/TaskController.cpp:373:36
#21 0x7f1b122b9146 in operator() src/xpcom/threads/TaskController.cpp:120:37
#22 0x7f1b122b9146 in mozilla::detail::RunnableFunction<mozilla::TaskController::InitializeInternal()::$_3>::Run() /builds/worker/workspace/obj-build/dist/include/nsThreadUtils.h:577:5
#23 0x7f1b122ca6c7 in nsThread::ProcessNextEvent(bool, bool*) src/xpcom/threads/nsThread.cpp:1197:14
#24 0x7f1b122d040a in NS_ProcessNextEvent(nsIThread*, bool) src/xpcom/threads/nsThreadUtils.cpp:513:10
#25 0x7f1b12bbbb66 in mozilla::ipc::MessagePump::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:87:21
#26 0x7f1b12b2da53 in MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:334:10
#27 0x7f1b12b2d96d in RunHandler src/ipc/chromium/src/base/message_loop.cc:327:3
#28 0x7f1b12b2d96d in MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:309:3
#29 0x7f1b16829348 in nsBaseAppShell::Run() src/widget/nsBaseAppShell.cpp:137:27
#30 0x7f1b18030a83 in XRE_RunAppShell() src/toolkit/xre/nsEmbedFunctions.cpp:913:20
#31 0x7f1b12bbc929 in mozilla::ipc::MessagePumpForChildProcess::Run(base::MessagePump::Delegate*) src/ipc/glue/MessagePump.cpp:237:9
#32 0x7f1b12b2da53 in MessageLoop::RunInternal() src/ipc/chromium/src/base/message_loop.cc:334:10
#33 0x7f1b12b2d96d in RunHandler src/ipc/chromium/src/base/message_loop.cc:327:3
#34 0x7f1b12b2d96d in MessageLoop::Run() src/ipc/chromium/src/base/message_loop.cc:309:3
#35 0x7f1b18030668 in XRE_InitChildProcess(int, char**, XREChildData const*) src/toolkit/xre/nsEmbedFunctions.cpp:744:34
#36 0x563424beba27 in content_process_main src/browser/app/../../ipc/contentproc/plugin-container.cpp:56:28
#37 0x563424beba27 in main src/browser/app/nsBrowserApp.cpp:304:18

Comment 1

[Tyson Smith [:tsmith]]

Attachment: test.woff2

Comment 2

[Tyson Smith [:tsmith]]

A Pernosco session is available here: https://pernos.co/debug/78CFfRJC3FGOTYsuDzcCbw/index.html

Comment 3

[Cameron McCormack (:heycam)]

Emilio, could this be related to your recent changes?

Comment 4

[Emilio Cobos Álvarez (:emilio)]

Attachment: Bug 1676543 - Remove some invalid assertions. r=heycam,#style

We might clear this flag in PostRebuildAllStyleData before actually
flushing style, so if the timing is wrong you can hit this assertion.

This doesn't impact correctness in any way that I can see.

Comment 5

[Emilio Cobos Álvarez (:emilio)]

The build doesn't have my changes, but it's an invalid assert anyways so worth fixing :)

Comment 6

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/5cfe11c0659a
Remove some invalid assertions. r=heycam

Comment 7

[Cristina Coroiu [:ccoroiu]]

https://hg.mozilla.org/mozilla-central/rev/5cfe11c0659a