[Driver] Add Scudo as a possible -fsanitize= option

Summary:
This change adds Scudo as a possible Sanitizer option via -fsanitize=.
This allows for easier static & shared linking of the Scudo library, it allows
us to enforce PIE (otherwise the security of the allocator is moot), and check
for incompatible Sanitizers combo.

In its current form, Scudo is not compatible with any other Sanitizer, but the
plan is to make it work in conjunction with UBsan (-fsanitize=scudo,undefined),
which will require additional work outside of the scope of this change.

Reviewers: eugenis, kcc, alekseyshl

Reviewed By: eugenis, alekseyshl

Subscribers: llvm-commits, srhines

Differential Revision: https://reviews.llvm.org/D39334

llvm-svn: 317337

3 files changed, 20 insertions, 16 deletions

diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index 32c1c43a5bd..8d9f32f8483 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -30,7 +30,7 @@ enum : SanitizerMask {
   NeedsUbsanCxxRt = Vptr | CFI,
   NotAllowedWithTrap = Vptr,
   NotAllowedWithMinimalRuntime = Vptr,
-  RequiresPIE = DataFlow,
+  RequiresPIE = DataFlow | Scudo,
   NeedsUnwindTables = Address | Thread | Memory | DataFlow,
   SupportsCoverage = Address | KernelAddress | Memory | Leak | Undefined |
                      Integer | Nullability | DataFlow | Fuzzer | FuzzerNoLink,
@@ -173,7 +173,7 @@ static SanitizerMask parseSanitizeTrapArgs(const Driver &D,
 bool SanitizerArgs::needsUbsanRt() const {
   // All of these include ubsan.
   if (needsAsanRt() || needsMsanRt() || needsTsanRt() || needsDfsanRt() ||
-      needsLsanRt() || needsCfiDiagRt())
+      needsLsanRt() || needsCfiDiagRt() || needsScudoRt())
     return false;
 
   return (Sanitizers.Mask & NeedsUbsanRt & ~TrapSanitizers.Mask) ||
@@ -370,17 +370,14 @@ SanitizerArgs::SanitizerArgs(const ToolChain &TC,
 
   // Warn about incompatible groups of sanitizers.
   std::pair<SanitizerMask, SanitizerMask> IncompatibleGroups[] = {
-      std::make_pair(Address, Thread), std::make_pair(Address, Memory),
-      std::make_pair(Thread, Memory), std::make_pair(Leak, Thread),
-      std::make_pair(Leak, Memory), std::make_pair(KernelAddress, Address),
-      std::make_pair(KernelAddress, Leak),
-      std::make_pair(KernelAddress, Thread),
-      std::make_pair(KernelAddress, Memory),
-      std::make_pair(Efficiency, Address),
-      std::make_pair(Efficiency, Leak),
-      std::make_pair(Efficiency, Thread),
-      std::make_pair(Efficiency, Memory),
-      std::make_pair(Efficiency, KernelAddress)};
+      std::make_pair(Address, Thread | Memory),
+      std::make_pair(Thread, Memory),
+      std::make_pair(Leak, Thread | Memory),
+      std::make_pair(KernelAddress, Address| Leak | Thread | Memory),
+      std::make_pair(Efficiency, Address | Leak | Thread | Memory |
+                                 KernelAddress),
+      std::make_pair(Scudo, Address | Leak | Thread | Memory | KernelAddress |
+                            Efficiency) };
   for (auto G : IncompatibleGroups) {
     SanitizerMask Group = G.first;
     if (Kinds & Group) {
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index b359cbb77ef..91f653a53e8 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -566,7 +566,6 @@ collectSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
       if (!Args.hasArg(options::OPT_shared) && !TC.getTriple().isAndroid())
         HelperStaticRuntimes.push_back("asan-preinit");
     }
-
     if (SanArgs.needsUbsanRt()) {
       if (SanArgs.requiresMinimalRuntime()) {
         SharedRuntimes.push_back("ubsan_minimal");
@@ -574,6 +573,8 @@ collectSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
         SharedRuntimes.push_back("ubsan_standalone");
       }
     }
+    if (SanArgs.needsScudoRt())
+      SharedRuntimes.push_back("scudo");
   }
 
   // The stats_client library is also statically linked into DSOs.
@@ -630,6 +631,11 @@ collectSanitizerRuntimes(const ToolChain &TC, const ArgList &Args,
   }
   if (SanArgs.needsEsanRt())
     StaticRuntimes.push_back("esan");
+  if (SanArgs.needsScudoRt()) {
+    StaticRuntimes.push_back("scudo");
+    if (SanArgs.linkCXXRuntimes())
+      StaticRuntimes.push_back("scudo_cxx");
+  }
 }
 
 // Should be called before we add system libraries (C++ ABI, libstdc++/libc++,
diff --git a/clang/lib/Driver/ToolChains/Linux.cpp b/clang/lib/Driver/ToolChains/Linux.cpp
index 613a9f3c88e..9b722166c5f 100644
--- a/clang/lib/Driver/ToolChains/Linux.cpp
+++ b/clang/lib/Driver/ToolChains/Linux.cpp
@@ -845,9 +845,10 @@ SanitizerMask Linux::getSupportedSanitizers() const {
     Res |= SanitizerKind::Memory;
   if (IsX86_64 || IsMIPS64)
     Res |= SanitizerKind::Efficiency;
-  if (IsX86 || IsX86_64) {
+  if (IsX86 || IsX86_64)
     Res |= SanitizerKind::Function;
-  }
+  if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsArmArch)
+    Res |= SanitizerKind::Scudo;
   return Res;
 }