all: use os/exec instead of internal/execabs

We added internal/execabs back in January 2021 in order to fix
a security problem caused by os/exec's handling of the current
directory. Now that os/exec has that code, internal/execabs is
superfluous and can be deleted.

This commit rewrites all the imports back to os/exec and
deletes internal/execabs.

For #43724.

Change-Id: Ib9736baf978be2afd42a1225e2ab3fd5d33d19df
Reviewed-on: https://go-review.googlesource.com/c/go/+/381375
Run-TryBot: Russ Cox <rsc@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@golang.org>
Auto-Submit: Russ Cox <rsc@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

39 files changed, 37 insertions, 80 deletions

diff --git a/src/cmd/api/goapi.go b/src/cmd/api/goapi.go
index b2a023a9b7..e6bf62df1f 100644
--- a/src/cmd/api/goapi.go
+++ b/src/cmd/api/goapi.go
@@ -16,10 +16,10 @@ import (
 	"go/parser"
 	"go/token"
 	"go/types"
-	exec "internal/execabs"
 	"io"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"runtime"
diff --git a/src/cmd/api/run.go b/src/cmd/api/run.go
index 3ceaae6b89..1ae629a032 100644
--- a/src/cmd/api/run.go
+++ b/src/cmd/api/run.go
@@ -11,11 +11,11 @@ package main
 import (
 	"errors"
 	"fmt"
-	exec "internal/execabs"
 	"internal/goversion"
 	"io/fs"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strconv"
diff --git a/src/cmd/cgo/out.go b/src/cmd/cgo/out.go
index adbb761e38..a27007ed1d 100644
--- a/src/cmd/cgo/out.go
+++ b/src/cmd/cgo/out.go
@@ -14,10 +14,10 @@ import (
 	"go/ast"
 	"go/printer"
 	"go/token"
-	exec "internal/execabs"
 	"internal/xcoff"
 	"io"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"sort"
diff --git a/src/cmd/cgo/util.go b/src/cmd/cgo/util.go
index 00d931b98a..779f7be225 100644
--- a/src/cmd/cgo/util.go
+++ b/src/cmd/cgo/util.go
@@ -8,9 +8,9 @@ import (
 	"bytes"
 	"fmt"
 	"go/token"
-	exec "internal/execabs"
 	"io/ioutil"
 	"os"
+	"os/exec"
 )
 
 // run runs the command argv, feeding in stdin on standard input.
diff --git a/src/cmd/compile/internal/ssa/html.go b/src/cmd/compile/internal/ssa/html.go
index d9a78b3962..1e6060ab32 100644
--- a/src/cmd/compile/internal/ssa/html.go
+++ b/src/cmd/compile/internal/ssa/html.go
@@ -9,9 +9,9 @@ import (
 	"cmd/internal/src"
 	"fmt"
 	"html"
-	exec "internal/execabs"
 	"io"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strconv"
 	"strings"
diff --git a/src/cmd/cover/func.go b/src/cmd/cover/func.go
index 76a16b3fc4..dffd3c1a05 100644
--- a/src/cmd/cover/func.go
+++ b/src/cmd/cover/func.go
@@ -15,9 +15,9 @@ import (
 	"go/ast"
 	"go/parser"
 	"go/token"
-	exec "internal/execabs"
 	"io"
 	"os"
+	"os/exec"
 	"path"
 	"path/filepath"
 	"runtime"
diff --git a/src/cmd/cover/testdata/toolexec.go b/src/cmd/cover/testdata/toolexec.go
index 458adaeaaa..1769efedbe 100644
--- a/src/cmd/cover/testdata/toolexec.go
+++ b/src/cmd/cover/testdata/toolexec.go
@@ -15,8 +15,8 @@
 package main
 
 import (
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"strings"
 )
 
diff --git a/src/cmd/dist/buildtool.go b/src/cmd/dist/buildtool.go
index 6450601476..8afa7f7867 100644
--- a/src/cmd/dist/buildtool.go
+++ b/src/cmd/dist/buildtool.go
@@ -310,8 +310,6 @@ func bootstrapFixImports(srcFile string) string {
 		if strings.HasPrefix(line, `import "`) || strings.HasPrefix(line, `import . "`) ||
 			inBlock && (strings.HasPrefix(line, "\t\"") || strings.HasPrefix(line, "\t. \"") || strings.HasPrefix(line, "\texec \"")) {
 			line = strings.Replace(line, `"cmd/`, `"bootstrap/cmd/`, -1)
-			// During bootstrap, must use plain os/exec.
-			line = strings.Replace(line, `exec "internal/execabs"`, `"os/exec"`, -1)
 			for _, dir := range bootstrapDirs {
 				if strings.HasPrefix(dir, "cmd/") {
 					continue
diff --git a/src/cmd/doc/dirs.go b/src/cmd/doc/dirs.go
index 489f490889..60ad6d30e6 100644
--- a/src/cmd/doc/dirs.go
+++ b/src/cmd/doc/dirs.go
@@ -7,9 +7,9 @@ package main
 import (
 	"bytes"
 	"fmt"
-	exec "internal/execabs"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"strings"
diff --git a/src/cmd/fix/typecheck.go b/src/cmd/fix/typecheck.go
index 8a18d61bf2..015a0eef2f 100644
--- a/src/cmd/fix/typecheck.go
+++ b/src/cmd/fix/typecheck.go
@@ -9,8 +9,8 @@ import (
 	"go/ast"
 	"go/parser"
 	"go/token"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"reflect"
 	"runtime"
diff --git a/src/cmd/go/internal/base/base.go b/src/cmd/go/internal/base/base.go
index c2d4e6b258..d4af4dbc4b 100644
--- a/src/cmd/go/internal/base/base.go
+++ b/src/cmd/go/internal/base/base.go
@@ -10,9 +10,9 @@ import (
 	"context"
 	"flag"
 	"fmt"
-	exec "internal/execabs"
 	"log"
 	"os"
+	"os/exec"
 	"strings"
 	"sync"
 
diff --git a/src/cmd/go/internal/bug/bug.go b/src/cmd/go/internal/bug/bug.go
index b4181b1e44..9c9e9dd68a 100644
--- a/src/cmd/go/internal/bug/bug.go
+++ b/src/cmd/go/internal/bug/bug.go
@@ -9,10 +9,10 @@ import (
 	"bytes"
 	"context"
 	"fmt"
-	exec "internal/execabs"
 	"io"
 	urlpkg "net/url"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"runtime"
diff --git a/src/cmd/go/internal/generate/generate.go b/src/cmd/go/internal/generate/generate.go
index a46f4f8908..fe1e3d46c0 100644
--- a/src/cmd/go/internal/generate/generate.go
+++ b/src/cmd/go/internal/generate/generate.go
@@ -12,10 +12,10 @@ import (
 	"fmt"
 	"go/parser"
 	"go/token"
-	exec "internal/execabs"
 	"io"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"strconv"
diff --git a/src/cmd/go/internal/modfetch/codehost/codehost.go b/src/cmd/go/internal/modfetch/codehost/codehost.go
index d8d4392baa..31dc811752 100644
--- a/src/cmd/go/internal/modfetch/codehost/codehost.go
+++ b/src/cmd/go/internal/modfetch/codehost/codehost.go
@@ -10,10 +10,10 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"fmt"
-	exec "internal/execabs"
 	"io"
 	"io/fs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"sync"
diff --git a/src/cmd/go/internal/modfetch/codehost/git.go b/src/cmd/go/internal/modfetch/codehost/git.go
index 34f453c855..9c8fd42833 100644
--- a/src/cmd/go/internal/modfetch/codehost/git.go
+++ b/src/cmd/go/internal/modfetch/codehost/git.go
@@ -8,11 +8,11 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	exec "internal/execabs"
 	"io"
 	"io/fs"
 	"net/url"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"sort"
 	"strconv"
diff --git a/src/cmd/go/internal/test/genflags.go b/src/cmd/go/internal/test/genflags.go
index 10f290090c..f50ae5c1e9 100644
--- a/src/cmd/go/internal/test/genflags.go
+++ b/src/cmd/go/internal/test/genflags.go
@@ -9,9 +9,9 @@ package main
 import (
 	"bytes"
 	"flag"
-	exec "internal/execabs"
 	"log"
 	"os"
+	"os/exec"
 	"strings"
 	"testing"
 	"text/template"
diff --git a/src/cmd/go/internal/test/internal/genflags/vetflag.go b/src/cmd/go/internal/test/internal/genflags/vetflag.go
index 2195cc3447..1448811af0 100644
--- a/src/cmd/go/internal/test/internal/genflags/vetflag.go
+++ b/src/cmd/go/internal/test/internal/genflags/vetflag.go
@@ -9,7 +9,7 @@ import (
 	"cmd/go/internal/base"
 	"encoding/json"
 	"fmt"
-	exec "internal/execabs"
+	"os/exec"
 	"regexp"
 	"sort"
 )
diff --git a/src/cmd/go/internal/test/test.go b/src/cmd/go/internal/test/test.go
index 50e6d5201b..4adf3acbe6 100644
--- a/src/cmd/go/internal/test/test.go
+++ b/src/cmd/go/internal/test/test.go
@@ -11,10 +11,10 @@ import (
 	"errors"
 	"fmt"
 	"go/build"
-	exec "internal/execabs"
 	"io"
 	"io/fs"
 	"os"
+	"os/exec"
 	"path"
 	"path/filepath"
 	"regexp"
diff --git a/src/cmd/go/internal/tool/tool.go b/src/cmd/go/internal/tool/tool.go
index e8b55092d8..d61b524863 100644
--- a/src/cmd/go/internal/tool/tool.go
+++ b/src/cmd/go/internal/tool/tool.go
@@ -8,8 +8,8 @@ package tool
 import (
 	"context"
 	"fmt"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"os/signal"
 	"sort"
 	"strings"
diff --git a/src/cmd/go/internal/vcs/vcs.go b/src/cmd/go/internal/vcs/vcs.go
index 7dbcfb7cc4..4f16bef90c 100644
--- a/src/cmd/go/internal/vcs/vcs.go
+++ b/src/cmd/go/internal/vcs/vcs.go
@@ -8,13 +8,13 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	exec "internal/execabs"
 	"internal/lazyregexp"
 	"internal/singleflight"
 	"io/fs"
 	"log"
 	urlpkg "net/url"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"strconv"
diff --git a/src/cmd/go/internal/vet/vetflag.go b/src/cmd/go/internal/vet/vetflag.go
index 8a55e9cca0..eb7af6508d 100644
--- a/src/cmd/go/internal/vet/vetflag.go
+++ b/src/cmd/go/internal/vet/vetflag.go
@@ -10,9 +10,9 @@ import (
 	"errors"
 	"flag"
 	"fmt"
-	exec "internal/execabs"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 
diff --git a/src/cmd/go/internal/work/build.go b/src/cmd/go/internal/work/build.go
index e9a8ee6cb3..2f3c8c7554 100644
--- a/src/cmd/go/internal/work/build.go
+++ b/src/cmd/go/internal/work/build.go
@@ -9,8 +9,8 @@ import (
 	"errors"
 	"fmt"
 	"go/build"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strconv"
diff --git a/src/cmd/go/internal/work/buildid.go b/src/cmd/go/internal/work/buildid.go
index ac98aa344c..846e2c8b77 100644
--- a/src/cmd/go/internal/work/buildid.go
+++ b/src/cmd/go/internal/work/buildid.go
@@ -7,8 +7,8 @@ package work
 import (
 	"bytes"
 	"fmt"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"strings"
 
 	"cmd/go/internal/base"
diff --git a/src/cmd/go/internal/work/exec.go b/src/cmd/go/internal/work/exec.go
index 7c71d7e6e4..7f5fb774ea 100644
--- a/src/cmd/go/internal/work/exec.go
+++ b/src/cmd/go/internal/work/exec.go
@@ -12,13 +12,13 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	exec "internal/execabs"
 	"internal/lazyregexp"
 	"io"
 	"io/fs"
 	"log"
 	"math/rand"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"regexp"
 	"runtime"
diff --git a/src/cmd/go/internal/work/gccgo.go b/src/cmd/go/internal/work/gccgo.go
index 1499536932..cfd9bcc0c2 100644
--- a/src/cmd/go/internal/work/gccgo.go
+++ b/src/cmd/go/internal/work/gccgo.go
@@ -6,8 +6,8 @@ package work
 
 import (
 	"fmt"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"sync"
diff --git a/src/cmd/go/testdata/addmod.go b/src/cmd/go/testdata/addmod.go
index 41997a52ff..e378d7f31a 100644
--- a/src/cmd/go/testdata/addmod.go
+++ b/src/cmd/go/testdata/addmod.go
@@ -23,11 +23,11 @@ import (
 	"bytes"
 	"flag"
 	"fmt"
-	exec "internal/execabs"
 	"internal/txtar"
 	"io/fs"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 )
diff --git a/src/cmd/internal/browser/browser.go b/src/cmd/internal/browser/browser.go
index 577d31789f..6867c85d23 100644
--- a/src/cmd/internal/browser/browser.go
+++ b/src/cmd/internal/browser/browser.go
@@ -6,8 +6,8 @@
 package browser
 
 import (
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"runtime"
 	"time"
 )
diff --git a/src/cmd/internal/dwarf/dwarf.go b/src/cmd/internal/dwarf/dwarf.go
index be37641706..8ba57371e6 100644
--- a/src/cmd/internal/dwarf/dwarf.go
+++ b/src/cmd/internal/dwarf/dwarf.go
@@ -12,7 +12,7 @@ import (
 	"errors"
 	"fmt"
 	"internal/buildcfg"
-	exec "internal/execabs"
+	"os/exec"
 	"sort"
 	"strconv"
 	"strings"
diff --git a/src/cmd/internal/pkgpath/pkgpath.go b/src/cmd/internal/pkgpath/pkgpath.go
index 72e3bdb631..40a040a81a 100644
--- a/src/cmd/internal/pkgpath/pkgpath.go
+++ b/src/cmd/internal/pkgpath/pkgpath.go
@@ -10,9 +10,9 @@ import (
 	"bytes"
 	"errors"
 	"fmt"
-	exec "internal/execabs"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	"strings"
 )
 
diff --git a/src/cmd/link/internal/ld/execarchive.go b/src/cmd/link/internal/ld/execarchive.go
index 918b86cdc5..a9376e96a4 100644
--- a/src/cmd/link/internal/ld/execarchive.go
+++ b/src/cmd/link/internal/ld/execarchive.go
@@ -8,8 +8,8 @@
 package ld
 
 import (
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"syscall"
 )
diff --git a/src/cmd/link/internal/ld/lib.go b/src/cmd/link/internal/ld/lib.go
index d995f7676b..4aefa9991d 100644
--- a/src/cmd/link/internal/ld/lib.go
+++ b/src/cmd/link/internal/ld/lib.go
@@ -49,11 +49,11 @@ import (
 	"encoding/binary"
 	"fmt"
 	"internal/buildcfg"
-	exec "internal/execabs"
 	"io"
 	"io/ioutil"
 	"log"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
diff --git a/src/cmd/test2json/main.go b/src/cmd/test2json/main.go
index b1c2d0696d..5e17e0dec3 100644
--- a/src/cmd/test2json/main.go
+++ b/src/cmd/test2json/main.go
@@ -85,9 +85,9 @@ package main
 import (
 	"flag"
 	"fmt"
-	exec "internal/execabs"
 	"io"
 	"os"
+	"os/exec"
 
 	"cmd/internal/test2json"
 )
diff --git a/src/cmd/trace/pprof.go b/src/cmd/trace/pprof.go
index c4d3742820..a73ff5336a 100644
--- a/src/cmd/trace/pprof.go
+++ b/src/cmd/trace/pprof.go
@@ -9,11 +9,11 @@ package main
 import (
 	"bufio"
 	"fmt"
-	exec "internal/execabs"
 	"internal/trace"
 	"io"
 	"net/http"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"sort"
diff --git a/src/go/build/build.go b/src/go/build/build.go
index bfa9cd60fb..cf8886c787 100644
--- a/src/go/build/build.go
+++ b/src/go/build/build.go
@@ -13,13 +13,13 @@ import (
 	"go/doc"
 	"go/token"
 	"internal/buildcfg"
-	exec "internal/execabs"
 	"internal/goroot"
 	"internal/goversion"
 	"io"
 	"io/fs"
 	"io/ioutil"
 	"os"
+	"os/exec"
 	pathpkg "path"
 	"path/filepath"
 	"runtime"
diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go
index 330973567d..8e24ca937b 100644
--- a/src/go/build/deps_test.go
+++ b/src/go/build/deps_test.go
@@ -203,15 +203,10 @@ var depsRules = `
 
 	log !< FMT;
 
-	OS, FMT
-	< internal/execabs;
-
-	OS, internal/execabs
-	< internal/goroot;
-
 	# Misc packages needing only FMT.
 	FMT
 	< html,
+	  internal/goroot,
 	  mime/quotedprintable,
 	  net/internal/socktest,
 	  net/url,
diff --git a/src/go/internal/gccgoimporter/gccgoinstallation.go b/src/go/internal/gccgoimporter/gccgoinstallation.go
index e90a3cc0b0..8fc7ce3232 100644
--- a/src/go/internal/gccgoimporter/gccgoinstallation.go
+++ b/src/go/internal/gccgoimporter/gccgoinstallation.go
@@ -7,8 +7,8 @@ package gccgoimporter
 import (
 	"bufio"
 	"go/types"
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 )
diff --git a/src/go/internal/srcimporter/srcimporter.go b/src/go/internal/srcimporter/srcimporter.go
index ea6f01280a..caf76a24de 100644
--- a/src/go/internal/srcimporter/srcimporter.go
+++ b/src/go/internal/srcimporter/srcimporter.go
@@ -13,9 +13,9 @@ import (
 	"go/parser"
 	"go/token"
 	"go/types"
-	exec "internal/execabs"
 	"io"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"sync"
diff --git a/src/internal/execabs/execabs.go b/src/internal/execabs/execabs.go
deleted file mode 100644
index 5f60fbb119..0000000000
--- a/src/internal/execabs/execabs.go
+++ /dev/null
@@ -1,36 +0,0 @@
-// Copyright 2021 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.
-
-// Package execabs is a drop-in replacement for os/exec
-// that requires PATH lookups to find absolute paths.
-// That is, execabs.Command("cmd") runs the same PATH lookup
-// as exec.Command("cmd"), but if the result is a path
-// which is relative, the Run and Start methods will report
-// an error instead of running the executable.
-package execabs
-
-import (
-	"context"
-	"os/exec"
-)
-
-var ErrNotFound = exec.ErrNotFound
-
-type (
-	Cmd       = exec.Cmd
-	Error     = exec.Error
-	ExitError = exec.ExitError
-)
-
-func LookPath(file string) (string, error) {
-	return exec.LookPath(file)
-}
-
-func CommandContext(ctx context.Context, name string, arg ...string) *exec.Cmd {
-	return exec.CommandContext(ctx, name, arg...)
-}
-
-func Command(name string, arg ...string) *exec.Cmd {
-	return exec.Command(name, arg...)
-}
diff --git a/src/internal/goroot/gc.go b/src/internal/goroot/gc.go
index 8c66cd13a8..79403d29fc 100644
--- a/src/internal/goroot/gc.go
+++ b/src/internal/goroot/gc.go
@@ -7,8 +7,8 @@
 package goroot
 
 import (
-	exec "internal/execabs"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"strings"
 	"sync"