From: Arthur Eubanks <aeubanks@google.com>
Date: Tue, 27 Sep 2022 00:41:37 +0000 (-0700)
Subject: [clang][msan] Turn on -fsanitize-memory-param-retval by default
X-Git-Tag: upstream/17.0.6~32247
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=44ad67031cc1a10483337f8b1f728e2be237685e;p=platform%2Fupstream%2Fllvm.git

[clang][msan] Turn on -fsanitize-memory-param-retval by default

This eagerly reports use of undef values when passed to noundef
parameters or returned from noundef functions.

This also decreases binary sizes under msan.

To go back to the previous behavior, pass `-fno-sanitize-memory-param-retval`.

Reviewed By: vitalybuka, MaskRay

Differential Revision: https://reviews.llvm.org/D134669
---

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 0bae33c..ee31da3 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -447,10 +447,15 @@ Static Analyzer
   ``scanbuild`` was also updated accordingly.
   Passing these flags will result in a hard error.
 
-.. _release-notes-ubsan:
-
-Undefined Behavior Sanitizer (UBSan)
-------------------------------------
+.. _release-notes-sanitizers:
+
+Sanitizers
+----------
+- ``-fsanitize-memory-param-retval`` is turned on by default. With
+  ``-fsanitize=memory``, passing uninitialized variables to functions and
+  returning uninitialized variables from functions is more aggressively
+  reported. ``-fno-sanitize-memory-param-retval`` restores the previous
+  behavior.
 
 Core Analysis Improvements
 ==========================
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 429ab38..61ffaf9 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -1767,7 +1767,7 @@ def sanitize_address_destructor_EQ
 defm sanitize_memory_param_retval
     : BoolFOption<"sanitize-memory-param-retval",
         CodeGenOpts<"SanitizeMemoryParamRetval">,
-        DefaultFalse,
+        DefaultTrue,
         PosFlag<SetTrue, [CC1Option], "Enable">, NegFlag<SetFalse, [], "Disable">,
         BothFlags<[], " detection of uninitialized parameters and return values">>;
 //// Note: This flag was introduced when it was necessary to distinguish between
diff --git a/clang/include/clang/Driver/SanitizerArgs.h b/clang/include/clang/Driver/SanitizerArgs.h
index 65677f7..52889c3 100644
--- a/clang/include/clang/Driver/SanitizerArgs.h
+++ b/clang/include/clang/Driver/SanitizerArgs.h
@@ -34,7 +34,7 @@ class SanitizerArgs {
   int BinaryMetadataFeatures = 0;
   int MsanTrackOrigins = 0;
   bool MsanUseAfterDtor = true;
-  bool MsanParamRetval = false;
+  bool MsanParamRetval = true;
   bool CfiCrossDso = false;
   bool CfiICallGeneralizePointers = false;
   bool CfiCanonicalJumpTables = false;
diff --git a/clang/lib/Driver/SanitizerArgs.cpp b/clang/lib/Driver/SanitizerArgs.cpp
index 631cf00..edbb762 100644
--- a/clang/lib/Driver/SanitizerArgs.cpp
+++ b/clang/lib/Driver/SanitizerArgs.cpp
@@ -1184,8 +1184,8 @@ void SanitizerArgs::addArgs(const ToolChain &TC, const llvm::opt::ArgList &Args,
   if (MsanUseAfterDtor)
     CmdArgs.push_back("-fsanitize-memory-use-after-dtor");
 
-  if (MsanParamRetval)
-    CmdArgs.push_back("-fsanitize-memory-param-retval");
+  if (!MsanParamRetval)
+    CmdArgs.push_back("-fno-sanitize-memory-param-retval");
 
   // FIXME: Pass these parameters as function attributes, not as -llvm flags.
   if (!TsanMemoryAccess) {
diff --git a/clang/test/CodeGen/kmsan-param-retval.c b/clang/test/CodeGen/kmsan-param-retval.c
index 3d952c0..dd7e1f5 100644
--- a/clang/test/CodeGen/kmsan-param-retval.c
+++ b/clang/test/CodeGen/kmsan-param-retval.c
@@ -1,12 +1,12 @@
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -no-enable-noundef-analysis -o - %s | \
 // RUN:     FileCheck %s --check-prefix=CLEAN
-// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -o - %s | \
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -fno-sanitize-memory-param-retval -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,NOUNDEF_ONLY
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -mllvm -msan-eager-checks -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,EAGER
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -no-enable-noundef-analysis -fsanitize-memory-param-retval -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=CLEAN
-// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -fsanitize-memory-param-retval -o - %s | \
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -O2 -fsanitize=kernel-memory -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,EAGER
 
 void foo();
diff --git a/clang/test/CodeGen/msan-param-retval.c b/clang/test/CodeGen/msan-param-retval.c
index 5bb597f..fffb6cb 100644
--- a/clang/test/CodeGen/msan-param-retval.c
+++ b/clang/test/CodeGen/msan-param-retval.c
@@ -1,12 +1,12 @@
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -no-enable-noundef-analysis -o - %s | \
 // RUN:     FileCheck %s --check-prefix=CLEAN
-// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -o - %s | \
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -fno-sanitize-memory-param-retval -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,NOUNDEF_ONLY
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -mllvm -msan-eager-checks -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,EAGER
 // RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -no-enable-noundef-analysis -fsanitize-memory-param-retval -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=CLEAN
-// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -fsanitize-memory-param-retval -o - %s | \
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -S -emit-llvm -fsanitize=memory -o - %s | \
 // RUN:     FileCheck %s --check-prefixes=NOUNDEF,EAGER
 
 void bar(int x) {
diff --git a/clang/test/Driver/fsanitize-memory-param-retval.c b/clang/test/Driver/fsanitize-memory-param-retval.c
index d82d208..79ade32 100644
--- a/clang/test/Driver/fsanitize-memory-param-retval.c
+++ b/clang/test/Driver/fsanitize-memory-param-retval.c
@@ -1,14 +1,14 @@
-// RUN: %clang -target i386-gnu-linux %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
-// RUN: %clang -target x86_64-linux-gnu %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
-// RUN: %clang -target aarch64-linux-gnu %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
-// RUN: %clang -target riscv32-linux-gnu %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
-// RUN: %clang -target riscv64-linux-gnu %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
-// RUN: %clang -target x86_64-linux-gnu %s -fsanitize=kernel-memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target i386-gnu-linux %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target x86_64-linux-gnu %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target aarch64-linux-gnu %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target riscv32-linux-gnu %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target riscv64-linux-gnu %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
+// RUN: %clang -target x86_64-linux-gnu %s -fsanitize=kernel-memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck %s
 
-// CHECK: "-fsanitize-memory-param-retval"
+// CHECK: "-fno-sanitize-memory-param-retval"
 
-// RUN: %clang -target aarch64-linux-gnu -fsyntax-only %s -fsanitize=memory -fsanitize-memory-param-retval -c -### 2>&1 | FileCheck --check-prefix=11 %s
-// 11: "-fsanitize-memory-param-retval"
+// RUN: %clang -target aarch64-linux-gnu -fsyntax-only %s -fsanitize=memory -fno-sanitize-memory-param-retval -c -### 2>&1 | FileCheck --check-prefix=11 %s
+// 11: "-fno-sanitize-memory-param-retval"
 
-// RUN: not %clang -target x86_64-linux-gnu -fsyntax-only %s -fsanitize=memory -fsanitize-memory-param-retval=1 2>&1 | FileCheck --check-prefix=EXCESS %s
-// EXCESS: error: unknown argument: '-fsanitize-memory-param-retval=
+// RUN: not %clang -target x86_64-linux-gnu -fsyntax-only %s -fsanitize=memory -fno-sanitize-memory-param-retval=1 2>&1 | FileCheck --check-prefix=EXCESS %s
+// EXCESS: error: unknown argument: '-fno-sanitize-memory-param-retval=