Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

[NativeAOT/x86] Add SAFESEH support to assembly files and ObjectWriter #100433

Merged
merged 6 commits into from
Mar 29, 2024
Merged
Show file tree
Hide file tree
Changes from 4 commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
Expand Up @@ -95,6 +95,7 @@ The .NET Foundation licenses this file to you under the MIT license.
<LinkerArg Condition="'$(OutputType)' == 'WinExe' or '$(OutputType)' == 'Exe'" Include="/ENTRY:$(EntryPointSymbol) /NOEXP /NOIMPLIB" />
<LinkerArg Include="/NATVIS:&quot;$(MSBuildThisFileDirectory)NativeAOT.natvis&quot;" />
<LinkerArg Condition="'$(ControlFlowGuard)' == 'Guard'" Include="/guard:cf" />
<LinkerArg Condition="'$(_targetArchitecture)' == 'x86'" Include="/safeseh" />
<LinkerArg Condition="'$(OutputType)' == 'WinExe' or '$(OutputType)' == 'Exe'" Include="/STACK:$(IlcDefaultStackSize)" />
<!-- Do not warn if someone declares UnmanagedCallersOnly with an entrypoint of 'DllGetClassObject' and similar -->
<LinkerArg Include="/IGNORE:4104" />
Expand Down
3 changes: 3 additions & 0 deletions src/coreclr/nativeaot/Runtime/CMakeLists.txt
Original file line number Diff line number Diff line change
Expand Up @@ -264,6 +264,9 @@ if(CLR_CMAKE_TARGET_WIN32)
if (CLR_CMAKE_TARGET_ARCH_AMD64)
add_definitions(-DFEATURE_SPECIAL_USER_MODE_APC)
endif()
if (CLR_CMAKE_TARGET_ARCH_I386)
set_source_files_properties(${RUNTIME_SOURCES_ARCH_ASM} PROPERTIES COMPILE_FLAGS "/safeseh")
endif (CLR_CMAKE_TARGET_ARCH_I386)
filipnavara marked this conversation as resolved.
Show resolved Hide resolved
else()
if(NOT CLR_CMAKE_TARGET_APPLE)
add_definitions(-DFEATURE_READONLY_GS_COOKIE)
Expand Down
Original file line number Diff line number Diff line change
Expand Up @@ -213,6 +213,8 @@ private protected override void EmitSymbolTable(
IDictionary<string, SymbolDefinition> definedSymbols,
SortedSet<string> undefinedSymbols)
{
Feat00Flags feat00Flags = _machine is Machine.I386 ? Feat00Flags.SafeSEH : 0;

foreach (var (symbolName, symbolDefinition) in definedSymbols)
{
if (_symbolNameToIndex.TryGetValue(symbolName, out uint symbolIndex))
Expand Down Expand Up @@ -253,13 +255,18 @@ private protected override void EmitSymbolTable(
gfidsSectionWriter.WriteLittleEndian<uint>(_symbolNameToIndex[symbolName]);
}

feat00Flags |= Feat00Flags.ControlFlowGuard;
}

if (feat00Flags != 0)
{
// Emit the feat.00 symbol that controls various linker behaviors
_symbols.Add(new CoffSymbol
{
Name = "@feat.00",
StorageClass = CoffSymbolClass.IMAGE_SYM_CLASS_STATIC,
SectionIndex = uint.MaxValue, // IMAGE_SYM_ABSOLUTE
Value = 0x800, // cfGuardCF flags this object as control flow guard aware
Value = (uint)feat00Flags,
});
}
}
Expand Down Expand Up @@ -1118,5 +1125,14 @@ public static uint CalculateChecksum(Stream stream)
return crc;
}
}

private enum Feat00Flags : uint
{
SafeSEH = 1,
StackGuard = 0x100,
SoftwareDevelopmentLifecycle = 0x200,
ControlFlowGuard = 0x800,
ExceptionContinuationMetadata = 0x4000,
}
}
}
Loading