misc/cgo/test: add asan and msan arena tests

While we're here, replace a couple uses of os.Environ with cmd.Environ.

For #51317.

Change-Id: Ic5cf4a887a7975a8281223eec0f94df230b6f095
Reviewed-on: https://go-review.googlesource.com/c/go/+/431955
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>

diff --git a/misc/cgo/testsanitizers/asan_test.go b/misc/cgo/testsanitizers/asan_test.go
index 1c423add16c5fa0021c5c2d4ba06329e16ddf9d5..67d097cf161694cef87410b4c4e703f4a6c46e56 100644 (file)
--- a/misc/cgo/testsanitizers/asan_test.go
+++ b/misc/cgo/testsanitizers/asan_test.go
@@ -42,6 +42,7 @@ func TestASAN(t *testing.T) {
                src               string
                memoryAccessError string
                errorLocation     string
+               experiments       []string
        }{
                {src: "asan1_fail.go", memoryAccessError: "heap-use-after-free", errorLocation: "asan1_fail.go:25"},
                {src: "asan2_fail.go", memoryAccessError: "heap-buffer-overflow", errorLocation: "asan2_fail.go:31"},
@@ -57,6 +58,7 @@ func TestASAN(t *testing.T) {
                {src: "asan_global3_fail.go", memoryAccessError: "global-buffer-overflow", errorLocation: "asan_global3_fail.go:13"},
                {src: "asan_global4_fail.go", memoryAccessError: "global-buffer-overflow", errorLocation: "asan_global4_fail.go:21"},
                {src: "asan_global5.go"},
+               {src: "arena_fail.go", memoryAccessError: "use-after-poison", errorLocation: "arena_fail.go:26", experiments: []string{"arenas"}},
        }
        for _, tc := range cases {
                tc := tc
@@ -68,7 +70,7 @@ func TestASAN(t *testing.T) {
                        defer dir.RemoveAll(t)
 
                        outPath := dir.Join(name)
-                       mustRun(t, config.goCmd("build", "-o", outPath, srcPath(tc.src)))
+                       mustRun(t, config.goCmdWithExperiments("build", []string{"-o", outPath, srcPath(tc.src)}, tc.experiments))
 
                        cmd := hangProneCmd(outPath)
                        if tc.memoryAccessError != "" {

diff --git a/misc/cgo/testsanitizers/cc_test.go b/misc/cgo/testsanitizers/cc_test.go
index 72af42660d3a6b7283fedaaf66d2e3159a297c0a..3c67448dcdb7341306947b862924b628b38d0f15 100644 (file)
--- a/misc/cgo/testsanitizers/cc_test.go
+++ b/misc/cgo/testsanitizers/cc_test.go
@@ -83,11 +83,26 @@ func goEnv(key string) (string, error) {
 // replaceEnv sets the key environment variable to value in cmd.
 func replaceEnv(cmd *exec.Cmd, key, value string) {
        if cmd.Env == nil {
-               cmd.Env = os.Environ()
+               cmd.Env = cmd.Environ()
        }
        cmd.Env = append(cmd.Env, key+"="+value)
 }
 
+// appendExperimentEnv appends comma-separated experiments to GOEXPERIMENT.
+func appendExperimentEnv(cmd *exec.Cmd, experiments []string) {
+       if cmd.Env == nil {
+               cmd.Env = cmd.Environ()
+       }
+       exps := strings.Join(experiments, ",")
+       for _, evar := range cmd.Env {
+               c := strings.SplitN(evar, "=", 2)
+               if c[0] == "GOEXPERIMENT" {
+                       exps = c[1] + "," + exps
+               }
+       }
+       cmd.Env = append(cmd.Env, "GOEXPERIMENT="+exps)
+}
+
 // mustRun executes t and fails cmd with a well-formatted message if it fails.
 func mustRun(t *testing.T, cmd *exec.Cmd) {
        t.Helper()
@@ -352,11 +367,19 @@ func configure(sanitizer string) *config {
 // goCmd returns a Cmd that executes "go $subcommand $args" with appropriate
 // additional flags and environment.
 func (c *config) goCmd(subcommand string, args ...string) *exec.Cmd {
+       return c.goCmdWithExperiments(subcommand, args, nil)
+}
+
+// goCmdWithExperiments returns a Cmd that executes
+// "GOEXPERIMENT=$experiments go $subcommand $args" with appropriate
+// additional flags and CGO-related environment variables.
+func (c *config) goCmdWithExperiments(subcommand string, args []string, experiments []string) *exec.Cmd {
        cmd := exec.Command("go", subcommand)
        cmd.Args = append(cmd.Args, c.goFlags...)
        cmd.Args = append(cmd.Args, args...)
        replaceEnv(cmd, "CGO_CFLAGS", strings.Join(c.cFlags, " "))
        replaceEnv(cmd, "CGO_LDFLAGS", strings.Join(c.ldFlags, " "))
+       appendExperimentEnv(cmd, experiments)
        return cmd
 }
 

diff --git a/misc/cgo/testsanitizers/msan_test.go b/misc/cgo/testsanitizers/msan_test.go
index 5ee9947a58504faa5f94e22b6419a7c46e882948..4043e3ecf9f4101f88d6f1e0e00095b12f66de4c 100644 (file)
--- a/misc/cgo/testsanitizers/msan_test.go
+++ b/misc/cgo/testsanitizers/msan_test.go
@@ -31,8 +31,9 @@ func TestMSAN(t *testing.T) {
        mustRun(t, config.goCmd("build", "std"))
 
        cases := []struct {
-               src     string
-               wantErr bool
+               src         string
+               wantErr     bool
+               experiments []string
        }{
                {src: "msan.go"},
                {src: "msan2.go"},
@@ -44,6 +45,11 @@ func TestMSAN(t *testing.T) {
                {src: "msan7.go"},
                {src: "msan8.go"},
                {src: "msan_fail.go", wantErr: true},
+               // This may not always fail specifically due to MSAN. It may sometimes
+               // fail because of a fault. However, we don't care what kind of error we
+               // get here, just that we get an error. This is an MSAN test because without
+               // MSAN it would not fail deterministically.
+               {src: "arena_fail.go", wantErr: true, experiments: []string{"arenas"}},
        }
        for _, tc := range cases {
                tc := tc
@@ -55,7 +61,7 @@ func TestMSAN(t *testing.T) {
                        defer dir.RemoveAll(t)
 
                        outPath := dir.Join(name)
-                       mustRun(t, config.goCmd("build", "-o", outPath, srcPath(tc.src)))
+                       mustRun(t, config.goCmdWithExperiments("build", []string{"-o", outPath, srcPath(tc.src)}, tc.experiments))
 
                        cmd := hangProneCmd(outPath)
                        if tc.wantErr {

diff --git a/misc/cgo/testsanitizers/testdata/arena_fail.go b/misc/cgo/testsanitizers/testdata/arena_fail.go
new file mode 100644 (file)
index 0000000..5b6c52e
--- /dev/null
+++ b/misc/cgo/testsanitizers/testdata/arena_fail.go
@@ -0,0 +1,27 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build goexperiment.arenas
+
+package main
+
+import "arena"
+
+func main() {
+       a := arena.NewArena()
+       x := arena.New[[200]byte](a)
+       x[0] = 9
+       a.Free()
+       // Use after free.
+       //
+       // ASAN should detect this deterministically as Free
+       // should poison the arena memory.
+       //
+       // MSAN should detect that this access is to freed
+       // memory. This may crash with an "accessed freed arena
+       // memory" error before MSAN gets a chance, but if MSAN
+       // was not enabled there would be a chance that this
+       // could fail to crash on its own.
+       println(x[0])
+}