Dotnet apps fail to start when run in a directory containing a backslash

[Penguinwizzard]

Description

If a dotnet self-contained app starts up from a path where a component contains a backslash (e.g. /home/cooluser/fancy\folder/app_binary, where one of the folders in the path is named fancy\folder, with a backslash in the folder name), the runtime startup will fail, and the cryptic error message Failed to create CoreCLR, HRESULT: 0x80004005 will be displayed.

Reproduction Steps

mkdir test_console_app
cd test_console_app
dotnet new console
dotnet publish --self-contained -p:PublishSingleFile=true test_console_app.csproj --runtime linux-x64 --self-contained true --configuration Release --framework net6.0
mkdir s\\test
cp bin/Release/net6.0/linux-x64/publish/test_console_app s\\test/
s\\test/test_console_app

Expected behavior

The app should run. Failing that, an error message that provides relevant information should be displayed.

Actual behavior

The app crashes with the message

Failed to create CoreCLR, HRESULT: 0x80004005

Regression?

Unknown.

Known Workarounds

Run from only paths without backslashes in folder names.

Configuration

• Reproduced in dotnet 6.0.400
• Any OS supporting backslashes in folder names (reproduced on multiple Linux distros and OSX)
• Any architecture tested
• Most likely specific to self-contained apps
• Before any user code (Blazor/non-Blazor irrelevant)

Other information

If you run the app with COREHOST_TRACE=3, you still don't get anything terribly useful; it continues exactly as per normal until it prints Failed to create CoreCLR, HRESULT: 0x80004005 to the log and immediately exits.

Tagging subscribers to this area: @vitek-karas, @agocke, @VSadov
See info in area-owners.md if you want to be subscribed.

Issue Details

---

Description

If a dotnet self-contained app starts up from a path where a component contains a backslash (e.g. /home/cooluser/fancy\folder/app_binary, where one of the folders in the path is named fancy\folder, with a backslash in the folder name), the runtime startup will fail, and the cryptic error message Failed to create CoreCLR, HRESULT: 0x80004005 will be displayed.

Reproduction Steps

mkdir test_console_app
cd test_console_app
dotnet new console
dotnet publish --self-contained -p:PublishSingleFile=true test_console_app.csproj --runtime linux-x64 --self-contained true --configuration Release --framework net6.0
mkdir s\\test
cp bin/Release/net6.0/linux-x64/publish/test_console_app s\\test/
s\\test/test_console_app

Expected behavior

The app should run. Failing that, an error message that provides relevant information should be displayed.

Actual behavior

The app crashes with the message

Failed to create CoreCLR, HRESULT: 0x80004005

Regression?

Unknown.

Known Workarounds

Run from only paths without backslashes in folder names.

Configuration

• Reproduced in dotnet 6.0.400
• Any OS supporting backslashes in folder names (reproduced on multiple Linux distros and OSX)
• Any architecture tested
• Most likely specific to self-contained apps
• Before any user code (Blazor/non-Blazor irrelevant)

Other information

If you run the app with COREHOST_TRACE=3, you still don't get anything terribly useful; it continues exactly as per normal until it prints Failed to create CoreCLR, HRESULT: 0x80004005 to the log and immediately exits.

Author:	Penguinwizzard
Assignees:	-
Labels:	area-Host, untriaged
Milestone:	-

[vitek-karas]

#75097 should be able to tell us more.
@janvorli maybe you can try the repro of this as a test for your change?

[janvorli]

I have debugged it too. With my change #75097, which besides adding logging for E_FAIL also stopped reporting all failures in the EE initialization that resulted in an exception as E_FAIL we now get 0x80070002 instead, which is "not found" error. I've stepped through the code and the culprit is in FILEDosToUnixPathA called from CreateFileW, see the call stack below.
The problem is that this method converts all backslashes in filenames to forward ones. Which for any valid path containing backslash on Unix is obviously wrong.

* thread #1, name = 'test_console_ap', stop reason = step over
  * frame #0: 0x00007ffff77bf4aa libcoreclr.so`::FILEDosToUnixPathA(lpPath="/home/janvorli/test/test_console_app/s\\test/System.Private.CoreLib.dll") at path.cpp:465:14
    frame #1: 0x00007ffff77c0a73 libcoreclr.so`FILEDosToUnixPathA(lpPath=0x00007fffffffc398) at path.cpp:481:5
    frame #2: 0x00007ffff77ae3ac libcoreclr.so`CorUnix::InternalCreateFile(pThread=0x0000555555591780, lpFileName="/home/janvorli/test/test_console_app/s\\test/System.Private.CoreLib.dll", dwDesiredAccess=2147483648, dwShareMode=5, lpSecurityAttributes=0x0000000000000000, dwCreationDisposition=3, dwFlagsAndAttributes=128, hTemplateFile=0x0000000000000000, phFile=0x00007fffffffc508) at file.cpp:464:5
    frame #3: 0x00007ffff77afbfb libcoreclr.so`::CreateFileW(lpFileName=u"/home/janvorli/test/test_console_app/s\\test/System.Private.CoreLib.dll", dwDesiredAccess=2147483648, dwShareMode=5, lpSecurityAttributes=0x0000000000000000, dwCreationDisposition=3, dwFlagsAndAttributes=128, hTemplateFile=0x0000000000000000) at file.cpp:883:16
    frame #4: 0x00007ffff754d8df libcoreclr.so`CreateFileWrapper(lpFileName=u"/home/janvorli/test/test_console_app/s\\test/System.Private.CoreLib.dll", dwDesiredAccess=2147483648, dwShareMode=5, lpSecurityAttributes=0x0000000000000000, dwCreationDisposition=3, dwFlagsAndAttributes=128, hTemplateFile=0x0000000000000000) at longfilepathwrappers.cpp:111:19
    frame #5: 0x00007ffff70aa747 libcoreclr.so`PEImage::TryOpenFile(this=0x00005555555ab310, takeLock=false) at peimage.cpp:902:13
    frame #6: 0x00007ffff71c0b4d libcoreclr.so`::BinderAcquirePEImage(wszAssemblyPath=u"/home/janvorli/test/test_console_app/s\\test/System.Private.CoreLib.dll", ppPEImage=0x00007fffffffca70, bundleFileLocation=(Size = 0, Offset = 0, UncompresedSize = 0)) at coreassemblyspec.cpp:108:20
    frame #7: 0x00007ffff75d44b9 libcoreclr.so`BINDER_SPACE::AssemblyBinderCommon::GetAssembly(assemblyPath=0x00007fffffffd118, fIsInTPA=YES, ppAssembly=0x00007fffffffcc08, bundleFileLocation=(Size = 0, Offset = 0, UncompresedSize = 0)) at assemblybindercommon.cpp:1016:18
    frame #8: 0x00007ffff75d3d30 libcoreclr.so`BINDER_SPACE::AssemblyBinderCommon::BindToSystem(systemDirectory=0x00007fffffffd710, ppSystemAssembly=0x00007fffffffd6a8) at assemblybindercommon.cpp:283:14
    frame #9: 0x00007ffff75e0332 libcoreclr.so`DefaultAssemblyBinder::BindToSystem(this=0x0000555555624770, ppSystemAssembly=0x00007fffffffd9b8) at defaultassemblybinder.cpp:199:14
    frame #10: 0x00007ffff70a6032 libcoreclr.so`PEAssembly::DoOpenSystem() at peassembly.cpp:838:53
    frame #11: 0x00007ffff70a5a22 libcoreclr.so`PEAssembly::OpenSystem() at peassembly.cpp:810:18
    frame #12: 0x00007ffff6ef0d86 libcoreclr.so`SystemDomain::LoadBaseSystemClasses(this=0x00007ffff791ed80) at appdomain.cpp:1265:27
    frame #13: 0x00007ffff6ef0c88 libcoreclr.so`SystemDomain::Init(this=0x00007ffff791ed80) at appdomain.cpp:1144:5
    frame #14: 0x00007ffff7777adc libcoreclr.so`EEStartupHelper() at ceemain.cpp:924:33
    frame #15: 0x00007ffff7778ec4 libcoreclr.so`EEStartup(this=0x00007fffffffdfe8, p=0x0000000000000000)::$_1::operator()(void*) const at ceemain.cpp:1071:9
    frame #16: 0x00007ffff77767fb libcoreclr.so`EEStartup() at ceemain.cpp:1073:5
    frame #17: 0x00007ffff77765f1 libcoreclr.so`EnsureEEStarted() at ceemain.cpp:308:17
    frame #18: 0x00007ffff6f94132 libcoreclr.so`CorHost2::Start(this=0x0000555555593dd0) at corhost.cpp:100:14
    frame #19: 0x00007ffff6eec2a8 libcoreclr.so`::coreclr_initialize(exePath="/home/janvorli/test/test_console_app/s\\test/test_console_app", appDomainFriendlyName="clrhost", propertyCount=9, propertyKeys=0x00005555555c1d40, propertyValues=0x00005555555c1e70, hostHandle=0x00007fffffffe338, domainId=0x00007fffffffe334) at exports.cpp:279:16
    frame #20: 0x00007ffff798b1ef libhostpolicy.so`___lldb_unnamed_symbol218 + 783
    frame #21: 0x00007ffff799ad21 libhostpolicy.so`___lldb_unnamed_symbol310 + 385
    frame #22: 0x00007ffff799a5da libhostpolicy.so`corehost_main + 154
    frame #23: 0x00007ffff79f3be4 libhostfxr.so`___lldb_unnamed_symbol239 + 1812
    frame #24: 0x00007ffff79f2309 libhostfxr.so`___lldb_unnamed_symbol237 + 665
    frame #25: 0x00007ffff79ed6db libhostfxr.so`hostfxr_main_startupinfo + 171
    frame #26: 0x000055555556c4b5 test_console_app`___lldb_unnamed_symbol638 + 1045
    frame #27: 0x000055555556c990 test_console_app`___lldb_unnamed_symbol639 + 144
    frame #28: 0x00007ffff7a61d90 libc.so.6`__libc_start_call_main(main=(test_console_app`___lldb_unnamed_symbol639), argc=1, argv=0x00007fffffffe908) at libc_start_call_main.h:58:16
    frame #29: 0x00007ffff7a61e40 libc.so.6`__libc_start_main_impl(main=(test_console_app`___lldb_unnamed_symbol639), argc=1, argv=0x00007fffffffe908, init=0x00007ffff7ffd040, fini=<unavailable>, rtld_fini=<unavailable>, stack_end=0x00007fffffffe8f8) at libc-start.c:392:3
    frame #30: 0x0000555555560029 test_console_app`_start + 41

[janvorli]

If I patched the string at the FILEDosToUnixPathA to not do to any transformation, then it progressed further and as a next failure, it failed to load the JIT.

./test_console_app
Fatal error. Failed to load JIT compiler

Edit: I have forgotten to mention that I was debugging the non-single file version as it behaved the same as the single file and it is simpler to debug.

[janvorli]

My mistake, I have forgotten to copy over the jit I've built. So there were no further issues:

./test_console_app
Hello, World!

[janvorli]

Now as for the FILEDosToUnixPathA behavior. The point for it was that the CreateFile and other PAL emulated APIs working with file paths, can be called with Windows style paths from user apps that were ported from Windows. But clearly, its behavior is too big hammer in the scenario from this issue. I wonder though how to fix it without making a breaking change.

[jkotas]

We should make the breaking change.

99+% of the cases that take paths go through libraries shims that do not have this adjustment. It is just the few remaining cases that still go through the Win32 PAL have this odd behavior.