CFI: Print DSO names for failed cross-DSO icalls

Reviewers: pcc

Reviewed By: pcc

Subscribers: kubamracek, delcypher, llvm-commits, kcc, #sanitizers

Differential Revision: https://reviews.llvm.org/D48583

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@335644 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 32 insertions, 8 deletions

diff --git a/lib/ubsan/ubsan_handlers.cc b/lib/ubsan/ubsan_handlers.cc
index 2fe83f2bb..59a5a6b72 100644
--- a/lib/ubsan/ubsan_handlers.cc
+++ b/lib/ubsan/ubsan_handlers.cc
@@ -660,6 +660,21 @@ static void handleCFIBadIcall(CFICheckFailData *Data, ValueHandle Function,
   if (!FName)
     FName = "(unknown)";
   Diag(FLoc, DL_Note, ET, "%0 defined here") << FName;
+
+  // If the failure involved different DSOs for the check location and icall
+  // target, report the DSO names.
+  const char *DstModule = FLoc.get()->info.module;
+  if (!DstModule)
+    DstModule = "(unknown)";
+
+  const char *SrcModule = Symbolizer::GetOrInit()->GetModuleNameForPc(Opts.pc);
+  if (!SrcModule)
+    SrcModule = "(unknown)";
+
+  if (internal_strcmp(SrcModule, DstModule))
+    Diag(Loc, DL_Note, ET,
+         "check failed in %0, destination function located in %1")
+        << SrcModule << DstModule;
 }
 
 namespace __ubsan {
diff --git a/lib/ubsan/ubsan_handlers_cxx.cc b/lib/ubsan/ubsan_handlers_cxx.cc
index 6b205c2c6..85a3e8dad 100644
--- a/lib/ubsan/ubsan_handlers_cxx.cc
+++ b/lib/ubsan/ubsan_handlers_cxx.cc
@@ -137,16 +137,25 @@ void __ubsan_handle_cfi_bad_type(CFICheckFailData *Data, ValueHandle Vtable,
       << Data->Type << CheckKindStr << (void *)Vtable;
 
   // If possible, say what type it actually points to.
-  if (!DTI.isValid()) {
-    const char *module = Symbolizer::GetOrInit()->GetModuleNameForPc(Vtable);
-    if (module)
-      Diag(Vtable, DL_Note, ET, "invalid vtable in module %0") << module;
-    else
-      Diag(Vtable, DL_Note, ET, "invalid vtable");
-  } else {
+  if (!DTI.isValid())
+    Diag(Vtable, DL_Note, ET, "invalid vtable");
+  else
     Diag(Vtable, DL_Note, ET, "vtable is of type %0")
         << TypeName(DTI.getMostDerivedTypeName());
-  }
+
+  // If the failure involved different DSOs for the check location and vtable,
+  // report the DSO names.
+  const char *DstModule = Symbolizer::GetOrInit()->GetModuleNameForPc(Vtable);
+  if (!DstModule)
+    DstModule = "(unknown)";
+
+  const char *SrcModule = Symbolizer::GetOrInit()->GetModuleNameForPc(Opts.pc);
+  if (!SrcModule)
+    SrcModule = "(unknown)";
+
+  if (internal_strcmp(SrcModule, DstModule))
+    Diag(Loc, DL_Note, ET, "check failed in %0, vtable located in %1")
+        << SrcModule << DstModule;
 }
 }  // namespace __ubsan