proc/*: add launch option to disable ASLR (#2202)

Fixes #1847

Documentation/usage/dlv.md

@@ -25,6 +25,7 @@ Pass flags to the program you are debugging using `--`, for example:
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_attach.md

@@ -31,6 +31,7 @@ dlv attach pid [executable]
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_backend.md

@@ -24,6 +24,7 @@ are:
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_connect.md

@@ -20,6 +20,7 @@ dlv connect addr
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_core.md

@@ -26,6 +26,7 @@ dlv core <executable> <core>
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_dap.md

@@ -27,6 +27,7 @@ dlv dap
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_debug.md

@@ -33,6 +33,7 @@ dlv debug [package]
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_exec.md

@@ -33,6 +33,7 @@ dlv exec <path/to/binary>
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_log.md

@@ -39,6 +39,7 @@ and dap modes.
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_redirect.md

@@ -27,6 +27,7 @@ File redirects can also be changed using the 'restart' command.
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_replay.md

@@ -24,6 +24,7 @@ dlv replay [trace directory]
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_run.md

@@ -20,6 +20,7 @@ dlv run
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_test.md

@@ -31,6 +31,7 @@ dlv test [package]
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_trace.md

@@ -38,6 +38,7 @@ dlv trace [package] regexp
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

Documentation/usage/dlv_version.md

@@ -20,6 +20,7 @@ dlv version
       --backend string                   Backend selection (see 'dlv help backend'). (default "default")
       --build-flags string               Build flags, to be passed to the compiler.
       --check-go-version                 Checks that the version of Go in use is compatible with Delve. (default true)
+      --disable-aslr                     Disables address space randomization
       --headless                         Run debug server only, in headless mode.
       --init string                      Init file, executed by the terminal client.
   -l, --listen string                    Debugging server listen address. (default "127.0.0.1:0")

cmd/dlv/cmds/commands.go

@@ -58,6 +58,8 @@ var (
 	checkLocalConnUser bool
 	// tty is used to provide an alternate TTY for the program you wish to debug.
 	tty string
+	// disableASLR is used to disable ASLR
+	disableASLR bool
 
 	// backend selection
 	backend string
@@ -131,6 +133,7 @@ func New(docCall bool) *cobra.Command {
 	rootCommand.PersistentFlags().StringVar(&backend, "backend", "default", `Backend selection (see 'dlv help backend').`)
 	rootCommand.PersistentFlags().StringArrayVarP(&redirects, "redirect", "r", []string{}, "Specifies redirect rules for target process (see 'dlv help redirect')")
 	rootCommand.PersistentFlags().BoolVar(&allowNonTerminalInteractive, "allow-non-terminal-interactive", false, "Allows interactive sessions of Delve that don't have a terminal as stdin, stdout and stderr")
+	rootCommand.PersistentFlags().BoolVar(&disableASLR, "disable-aslr", false, "Disables address space randomization")
 
 	// 'attach' subcommand.
 	attachCommand := &cobra.Command{
@@ -842,6 +845,7 @@ func execute(attachPid int, processArgs []string, conf *config.Config, coreFile
 				CheckGoVersion:       checkGoVersion,
 				TTY:                  tty,
 				Redirects:            redirects,
+				DisableASLR:          disableASLR,
 			},
 		})
 	default:

pkg/proc/gdbserial/gdbserver.go

@@ -342,11 +342,13 @@ func getLdEnvVars() []string {
 // LLDBLaunch starts an instance of lldb-server and connects to it, asking
 // it to launch the specified target program with the specified arguments
 // (cmd) on the specified directory wd.
-func LLDBLaunch(cmd []string, wd string, foreground bool, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
+func LLDBLaunch(cmd []string, wd string, flags proc.LaunchFlags, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
 	if runtime.GOOS == "windows" {
 		return nil, ErrUnsupportedOS
 	}
 
+	foreground := flags&proc.LaunchForeground != 0
+
 	if foreground {
 		// Disable foregrounding if we can't open /dev/tty or debugserver will
 		// crash. See issue #1215.
@@ -400,6 +402,9 @@ func LLDBLaunch(cmd []string, wd string, foreground bool, debugInfoDirs []string
 		if logflags.LLDBServerOutput() {
 			args = append(args, "-g", "-l", "stdout")
 		}
+		if flags&proc.LaunchDisableASLR != 0 {
+			args = append(args, "-D")
+		}
 		args = append(args, "-F", "-R", fmt.Sprintf("127.0.0.1:%d", listener.Addr().(*net.TCPAddr).Port), "--")
 		args = append(args, cmd...)
 

pkg/proc/native/nonative_darwin.go

@@ -12,7 +12,7 @@ import (
 var ErrNativeBackendDisabled = errors.New("native backend disabled during compilation")
 
 // Launch returns ErrNativeBackendDisabled.
-func Launch(_ []string, _ string, _ bool, _ []string, _ string, _ [3]string) (*proc.Target, error) {
+func Launch(_ []string, _ string, _ proc.LaunchFlags, _ []string, _ string, _ [3]string) (*proc.Target, error) {
 	return nil, ErrNativeBackendDisabled
 }
 

pkg/proc/native/proc_darwin.go

@@ -37,7 +37,7 @@ type osProcessDetails struct {
 // custom fork/exec process in order to take advantage of
 // PT_SIGEXC on Darwin which will turn Unix signals into
 // Mach exceptions.
-func Launch(cmd []string, wd string, foreground bool, _ []string, _ string, _ [3]string) (*proc.Target, error) {
+func Launch(cmd []string, wd string, flags proc.LaunchFlags, _ []string, _ string, _ [3]string) (*proc.Target, error) {
 	argv0Go, err := filepath.Abs(cmd[0])
 	if err != nil {
 		return nil, err

pkg/proc/native/proc_freebsd.go

@@ -42,12 +42,14 @@ type osProcessDetails struct {
 // to be supplied to that process. `wd` is working directory of the program.
 // If the DWARF information cannot be found in the binary, Delve will look
 // for external debug files in the directories passed in.
-func Launch(cmd []string, wd string, foreground bool, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
+func Launch(cmd []string, wd string, flags proc.LaunchFlags, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
 	var (
 		process *exec.Cmd
 		err     error
 	)
 
+	foreground := flags&proc.LaunchForeground != 0
+
 	stdin, stdout, stderr, closefn, err := openRedirects(redirects, foreground)
 	if err != nil {
 		return nil, err

pkg/proc/native/proc_linux.go

@@ -36,6 +36,9 @@ const (
 	// version of the kernel ('T' is job control stop on modern 3.x+ kernels) we
 	// may want to differentiate at some point.
 	statusTraceStopT = 'T'
+
+	personalityGetPersonality = 0xffffffff // argument to pass to personality syscall to get the current personality
+	_ADDR_NO_RANDOMIZE        = 0x0040000  // ADDR_NO_RANDOMIZE linux constant
 )
 
 // osProcessDetails contains Linux specific
@@ -49,12 +52,14 @@ type osProcessDetails struct {
 // to be supplied to that process. `wd` is working directory of the program.
 // If the DWARF information cannot be found in the binary, Delve will look
 // for external debug files in the directories passed in.
-func Launch(cmd []string, wd string, foreground bool, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
+func Launch(cmd []string, wd string, flags proc.LaunchFlags, debugInfoDirs []string, tty string, redirects [3]string) (*proc.Target, error) {
 	var (
 		process *exec.Cmd
 		err     error
 	)
 
+	foreground := flags&proc.LaunchForeground != 0
+
 	stdin, stdout, stderr, closefn, err := openRedirects(redirects, foreground)
 	if err != nil {
 		return nil, err
@@ -73,6 +78,15 @@ func Launch(cmd []string, wd string, foreground bool, debugInfoDirs []string, tt
 		}
 	}()
 	dbp.execPtraceFunc(func() {
+		if flags&proc.LaunchDisableASLR != 0 {
+			oldPersonality, _, err := syscall.Syscall(sys.SYS_PERSONALITY, personalityGetPersonality, 0, 0)
+			if err == syscall.Errno(0) {
+				newPersonality := oldPersonality | _ADDR_NO_RANDOMIZE
+				syscall.Syscall(sys.SYS_PERSONALITY, newPersonality, 0, 0)
+				defer syscall.Syscall(sys.SYS_PERSONALITY, oldPersonality, 0, 0)
+			}
+		}
+
 		process = exec.Command(cmd[0])
 		process.Args = cmd
 		process.Stdin = stdin

pkg/proc/native/proc_windows.go

@@ -21,7 +21,7 @@ type osProcessDetails struct {
 }
 
 // Launch creates and begins debugging a new process.
-func Launch(cmd []string, wd string, foreground bool, _ []string, _ string, redirects [3]string) (*proc.Target, error) {
+func Launch(cmd []string, wd string, flags proc.LaunchFlags, _ []string, _ string, redirects [3]string) (*proc.Target, error) {
 	argv0Go, err := filepath.Abs(cmd[0])
 	if err != nil {
 		return nil, err

pkg/proc/proc_linux_test.go

@@ -14,7 +14,7 @@ func TestLoadingExternalDebugInfo(t *testing.T) {
 	fixture := protest.BuildFixture("locationsprog", 0)
 	defer os.Remove(fixture.Path)
 	stripAndCopyDebugInfo(fixture, t)
-	p, err := native.Launch(append([]string{fixture.Path}, ""), "", false, []string{filepath.Dir(fixture.Path)}, "", [3]string{})
+	p, err := native.Launch(append([]string{fixture.Path}, ""), "", 0, []string{filepath.Dir(fixture.Path)}, "", [3]string{})
 	if err != nil {
 		t.Fatal(err)
 	}

pkg/proc/proc_test.go

@@ -97,9 +97,9 @@ func withTestProcessArgs(name string, t testing.TB, wd string, args []string, bu
 
 	switch testBackend {
 	case "native":
-		p, err = native.Launch(append([]string{fixture.Path}, args...), wd, false, []string{}, "", [3]string{})
+		p, err = native.Launch(append([]string{fixture.Path}, args...), wd, 0, []string{}, "", [3]string{})
 	case "lldb":
-		p, err = gdbserial.LLDBLaunch(append([]string{fixture.Path}, args...), wd, false, []string{}, "", [3]string{})
+		p, err = gdbserial.LLDBLaunch(append([]string{fixture.Path}, args...), wd, 0, []string{}, "", [3]string{})
 	case "rr":
 		protest.MustHaveRecordingAllowed(t)
 		t.Log("recording")
@@ -2108,9 +2108,9 @@ func TestUnsupportedArch(t *testing.T) {
 
 	switch testBackend {
 	case "native":
-		p, err = native.Launch([]string{outfile}, ".", false, []string{}, "", [3]string{})
+		p, err = native.Launch([]string{outfile}, ".", 0, []string{}, "", [3]string{})
 	case "lldb":
-		p, err = gdbserial.LLDBLaunch([]string{outfile}, ".", false, []string{}, "", [3]string{})
+		p, err = gdbserial.LLDBLaunch([]string{outfile}, ".", 0, []string{}, "", [3]string{})
 	default:
 		t.Skip("test not valid for this backend")
 	}

pkg/proc/target.go

@@ -23,6 +23,13 @@ var (
 	ErrProcessDetached = errors.New("detached from the process")
 )
 
+type LaunchFlags uint8
+
+const (
+	LaunchForeground LaunchFlags = 1 << iota
+	LaunchDisableASLR
+)
+
 // Target represents the process being debugged.
 type Target struct {
 	Process

service/debugger/debugger.go

@@ -120,6 +120,9 @@ type Config struct {
 
 	// Redirects specifies redirect rules for stdin, stdout and stderr
 	Redirects [3]string
+
+	// DisableASLR disables ASLR
+	DisableASLR bool
 }
 
 // New creates a new Debugger. ProcessArgs specify the commandline arguments for the
@@ -222,11 +225,20 @@ func (d *Debugger) Launch(processArgs []string, wd string) (*proc.Target, error)
 	if err := verifyBinaryFormat(processArgs[0]); err != nil {
 		return nil, err
 	}
+
+	launchFlags := proc.LaunchFlags(0)
+	if d.config.Foreground {
+		launchFlags |= proc.LaunchForeground
+	}
+	if d.config.DisableASLR {
+		launchFlags |= proc.LaunchDisableASLR
+	}
+
 	switch d.config.Backend {
 	case "native":
-		return native.Launch(processArgs, wd, d.config.Foreground, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects)
+		return native.Launch(processArgs, wd, launchFlags, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects)
 	case "lldb":
-		return betterGdbserialLaunchError(gdbserial.LLDBLaunch(processArgs, wd, d.config.Foreground, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects))
+		return betterGdbserialLaunchError(gdbserial.LLDBLaunch(processArgs, wd, launchFlags, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects))
 	case "rr":
 		if d.target != nil {
 			// restart should not call us if the backend is 'rr'
@@ -268,9 +280,9 @@ func (d *Debugger) Launch(processArgs []string, wd string) (*proc.Target, error)
 
 	case "default":
 		if runtime.GOOS == "darwin" {
-			return betterGdbserialLaunchError(gdbserial.LLDBLaunch(processArgs, wd, d.config.Foreground, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects))
+			return betterGdbserialLaunchError(gdbserial.LLDBLaunch(processArgs, wd, launchFlags, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects))
 		}
-		return native.Launch(processArgs, wd, d.config.Foreground, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects)
+		return native.Launch(processArgs, wd, launchFlags, d.config.DebugInfoDirectories, d.config.TTY, d.config.Redirects)
 	default:
 		return nil, fmt.Errorf("unknown backend %q", d.config.Backend)
 	}

service/test/variables_test.go

@@ -131,9 +131,9 @@ func withTestProcessArgs(name string, t *testing.T, wd string, args []string, bu
 	var tracedir string
 	switch testBackend {
 	case "native":
-		p, err = native.Launch(append([]string{fixture.Path}, args...), wd, false, []string{}, "", [3]string{})
+		p, err = native.Launch(append([]string{fixture.Path}, args...), wd, 0, []string{}, "", [3]string{})
 	case "lldb":
-		p, err = gdbserial.LLDBLaunch(append([]string{fixture.Path}, args...), wd, false, []string{}, "", [3]string{})
+		p, err = gdbserial.LLDBLaunch(append([]string{fixture.Path}, args...), wd, 0, []string{}, "", [3]string{})
 	case "rr":
 		protest.MustHaveRecordingAllowed(t)
 		t.Log("recording")