hwasan: Instrument globals.

Globals are instrumented by adding a pointer tag to their symbol values
and emitting metadata into a special section that allows the runtime to tag
their memory when the library is loaded.

Due to order of initialization issues explained in more detail in the comments,
shadow initialization cannot happen during regular global initialization.
Instead, the location of the global section is marked using an ELF note,
and we require libc support for calling a function provided by the HWASAN
runtime when libraries are loaded and unloaded.

Based on ideas discussed with @evgeny777 in D56672.

Differential Revision: https://reviews.llvm.org/D65770

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@368102 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Driver/SanitizerArgs.cpp b/lib/Driver/SanitizerArgs.cpp
index 814e95200d9d17145867cbeb311bc7640e93ae58..8e59e19be350cdb004c5ee122a572468ae540485 100644 (file)
--- a/lib/Driver/SanitizerArgs.cpp
+++ b/lib/Driver/SanitizerArgs.cpp
@@ -1013,6 +1013,11 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
     CmdArgs.push_back(Args.MakeArgString("hwasan-abi=" + HwasanAbi));
   }
 
+  if (Sanitizers.has(SanitizerKind::HWAddress)) {
+    CmdArgs.push_back("-target-feature");
+    CmdArgs.push_back("+tagged-globals");
+  }
+
   // MSan: Workaround for PR16386.
   // ASan: This is mainly to help LSan with cases such as
   // https://github.com/google/sanitizers/issues/373

diff --git a/test/Driver/fsanitize.c b/test/Driver/fsanitize.c
index 9a2a3836d1543c1bc7c373e2654fb6fb821b3d6a..0caac04637d5279fc443d077da44f5e25a826ce5 100644 (file)
--- a/test/Driver/fsanitize.c
+++ b/test/Driver/fsanitize.c
@@ -843,7 +843,9 @@
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=hwaddress -fsanitize-hwaddress-abi=platform %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-HWASAN-PLATFORM-ABI
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=hwaddress -fsanitize-hwaddress-abi=foo %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-HWASAN-FOO-ABI
 // CHECK-HWASAN-INTERCEPTOR-ABI: "-default-function-attr" "hwasan-abi=interceptor"
+// CHECK-HWASAN-INTERCEPTOR-ABI: "-target-feature" "+tagged-globals"
 // CHECK-HWASAN-PLATFORM-ABI: "-default-function-attr" "hwasan-abi=platform"
+// CHECK-HWASAN-PLATFORM-ABI: "-target-feature" "+tagged-globals"
 // CHECK-HWASAN-FOO-ABI: error: invalid value 'foo' in '-fsanitize-hwaddress-abi=foo'
 
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=address,pointer-compare,pointer-subtract %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-POINTER-ALL