diff options
| -rw-r--r-- | doc/godebug.md | 6 | ||||
| -rw-r--r-- | doc/next/6-stdlib/99-minor/os/63703.md | 11 | ||||
| -rw-r--r-- | doc/next/6-stdlib/99-minor/path/filepath/63703.md | 6 | ||||
| -rw-r--r-- | src/internal/godebugs/table.go | 1 | ||||
| -rw-r--r-- | src/os/file_windows.go | 10 | ||||
| -rw-r--r-- | src/os/os_windows_test.go | 210 | ||||
| -rw-r--r-- | src/path/filepath/path_windows_test.go | 14 | ||||
| -rw-r--r-- | src/runtime/metrics/doc.go | 4 |
8 files changed, 160 insertions, 102 deletions
diff --git a/doc/godebug.md b/doc/godebug.md index 83b4bda89a..2b8852a7ec 100644 --- a/doc/godebug.md +++ b/doc/godebug.md @@ -139,6 +139,12 @@ At previous versions (`winsymlink=0`), mount points are treated as symlinks, and other reparse points with non-default [`os.ModeType`](/pkg/os#ModeType) bits (such as [`os.ModeDir`](/pkg/os#ModeDir)) do not have the `ModeIrregular` bit set. +Go 1.23 changed [`os.Readlink`](/pkg/os#Readlink) and [`filepath.EvalSymlinks`](/pkg/path/filepath#EvalSymlinks) +to avoid trying to normalize volumes to drive letters, which was not always even possible. +This behavior is controlled by the `winreadlinkvolume` setting. +For Go 1.23, it defaults to `winreadlinkvolume=1`. +Previous versions default to `winreadlinkvolume=0`. + ### Go 1.22 Go 1.22 adds a configurable limit to control the maximum acceptable RSA key size diff --git a/doc/next/6-stdlib/99-minor/os/63703.md b/doc/next/6-stdlib/99-minor/os/63703.md new file mode 100644 index 0000000000..581ea142ab --- /dev/null +++ b/doc/next/6-stdlib/99-minor/os/63703.md @@ -0,0 +1,11 @@ +On Windows, the [`os.Readlink`](/os#Readlink) function no longer tries +to resolve mount points to a canonical path. +This behavior is controlled by the `winsymlink` setting. +For Go 1.23, it defaults to `winsymlink=1`. +Previous versions default to `winsymlink=0`. + +On Windows, [`os.Readlink`](/pkg/path/filepath#EvalSymlinks) no longer tries +to normalize volumes to drive letters, which was not always even possible. +This behavior is controlled by the `winreadlinkvolume` setting. +For Go 1.23, it defaults to `winreadlinkvolume=1`. +Previous versions default to `winreadlinkvolume=0`.
\ No newline at end of file diff --git a/doc/next/6-stdlib/99-minor/path/filepath/63703.md b/doc/next/6-stdlib/99-minor/path/filepath/63703.md index f5dc76c46a..0aa0ba6fe3 100644 --- a/doc/next/6-stdlib/99-minor/path/filepath/63703.md +++ b/doc/next/6-stdlib/99-minor/path/filepath/63703.md @@ -3,3 +3,9 @@ mount points, which was a source of many inconsistencies and bugs. This behavior is controlled by the `winsymlink` setting. For Go 1.23, it defaults to `winsymlink=1`. Previous versions default to `winsymlink=0`. + +On Windows, [`filepath.EvalSymlinks`](/pkg/path/filepath#EvalSymlinks) no longer tries +to normalize volumes to drive letters, which was not always even possible. +This behavior is controlled by the `winreadlinkvolume` setting. +For Go 1.23, it defaults to `winreadlinkvolume=1`. +Previous versions default to `winreadlinkvolume=0`.
\ No newline at end of file diff --git a/src/internal/godebugs/table.go b/src/internal/godebugs/table.go index a944db39aa..d5ac707a18 100644 --- a/src/internal/godebugs/table.go +++ b/src/internal/godebugs/table.go @@ -49,6 +49,7 @@ var All = []Info{ {Name: "tlsmaxrsasize", Package: "crypto/tls"}, {Name: "tlsrsakex", Package: "crypto/tls", Changed: 22, Old: "1"}, {Name: "tlsunsafeekm", Package: "crypto/tls", Changed: 22, Old: "1"}, + {Name: "winreadlinkvolume", Package: "os", Changed: 22, Old: "0"}, {Name: "winsymlink", Package: "os", Changed: 22, Old: "0"}, {Name: "x509sha1", Package: "crypto/x509"}, {Name: "x509usefallbackroots", Package: "crypto/x509"}, diff --git a/src/os/file_windows.go b/src/os/file_windows.go index 22fd9e5d40..49fdd8d44d 100644 --- a/src/os/file_windows.go +++ b/src/os/file_windows.go @@ -6,6 +6,7 @@ package os import ( "errors" + "internal/godebug" "internal/poll" "internal/syscall/windows" "runtime" @@ -349,6 +350,8 @@ func openSymlink(path string) (syscall.Handle, error) { return h, nil } +var winreadlinkvolume = godebug.New("winreadlinkvolume") + // normaliseLinkPath converts absolute paths returned by // DeviceIoControl(h, FSCTL_GET_REPARSE_POINT, ...) // into paths acceptable by all Windows APIs. @@ -356,7 +359,7 @@ func openSymlink(path string) (syscall.Handle, error) { // // \??\C:\foo\bar into C:\foo\bar // \??\UNC\foo\bar into \\foo\bar -// \??\Volume{abc}\ into C:\ +// \??\Volume{abc}\ into \\?\Volume{abc}\ func normaliseLinkPath(path string) (string, error) { if len(path) < 4 || path[:4] != `\??\` { // unexpected path, return it as is @@ -371,7 +374,10 @@ func normaliseLinkPath(path string) (string, error) { return `\\` + s[4:], nil } - // handle paths, like \??\Volume{abc}\... + // \??\Volume{abc}\ + if winreadlinkvolume.Value() != "0" { + return `\\?\` + path[4:], nil + } h, err := openSymlink(path) if err != nil { diff --git a/src/os/os_windows_test.go b/src/os/os_windows_test.go index 09ccbaff3b..7e8b8bbf1f 100644 --- a/src/os/os_windows_test.go +++ b/src/os/os_windows_test.go @@ -29,6 +29,7 @@ import ( ) var winsymlink = godebug.New("winsymlink") +var winreadlinkvolume = godebug.New("winreadlinkvolume") // For TestRawConnReadWrite. type syscallDescriptor = syscall.Handle @@ -1252,110 +1253,123 @@ func TestRootDirAsTemp(t *testing.T) { } } -func testReadlink(t *testing.T, path, want string) { - got, err := os.Readlink(path) - if err != nil { - t.Error(err) - return - } - if got != want { - t.Errorf(`Readlink(%q): got %q, want %q`, path, got, want) - } -} - -func mklink(t *testing.T, link, target string) { - output, err := testenv.Command(t, "cmd", "/c", "mklink", link, target).CombinedOutput() - if err != nil { - t.Fatalf("failed to run mklink %v %v: %v %q", link, target, err, output) - } -} - -func mklinkj(t *testing.T, link, target string) { - output, err := testenv.Command(t, "cmd", "/c", "mklink", "/J", link, target).CombinedOutput() - if err != nil { - t.Fatalf("failed to run mklink %v %v: %v %q", link, target, err, output) - } -} - -func mklinkd(t *testing.T, link, target string) { - output, err := testenv.Command(t, "cmd", "/c", "mklink", "/D", link, target).CombinedOutput() +// replaceDriveWithVolumeID returns path with its volume name replaced with +// the mounted volume ID. E.g. C:\foo -> \\?\Volume{GUID}\foo. +func replaceDriveWithVolumeID(t *testing.T, path string) string { + t.Helper() + cmd := testenv.Command(t, "cmd", "/c", "mountvol", filepath.VolumeName(path), "/L") + out, err := cmd.CombinedOutput() if err != nil { - t.Fatalf("failed to run mklink %v %v: %v %q", link, target, err, output) + t.Fatalf("%v: %v\n%s", cmd, err, out) } + vol := strings.Trim(string(out), " \n\r") + return filepath.Join(vol, path[len(filepath.VolumeName(path)):]) } -func TestWindowsReadlink(t *testing.T) { - tmpdir, err := os.MkdirTemp("", "TestWindowsReadlink") - if err != nil { - t.Fatal(err) - } - defer os.RemoveAll(tmpdir) - - // Make sure tmpdir is not a symlink, otherwise tests will fail. - tmpdir, err = filepath.EvalSymlinks(tmpdir) - if err != nil { - t.Fatal(err) - } - chdir(t, tmpdir) - - vol := filepath.VolumeName(tmpdir) - output, err := testenv.Command(t, "cmd", "/c", "mountvol", vol, "/L").CombinedOutput() - if err != nil { - t.Fatalf("failed to run mountvol %v /L: %v %q", vol, err, output) - } - ntvol := strings.Trim(string(output), " \n\r") - - dir := filepath.Join(tmpdir, "dir") - err = os.MkdirAll(dir, 0777) - if err != nil { - t.Fatal(err) - } - - absdirjlink := filepath.Join(tmpdir, "absdirjlink") - mklinkj(t, absdirjlink, dir) - testReadlink(t, absdirjlink, dir) - - ntdirjlink := filepath.Join(tmpdir, "ntdirjlink") - mklinkj(t, ntdirjlink, ntvol+absdirjlink[len(filepath.VolumeName(absdirjlink)):]) - testReadlink(t, ntdirjlink, absdirjlink) - - ntdirjlinktolink := filepath.Join(tmpdir, "ntdirjlinktolink") - mklinkj(t, ntdirjlinktolink, ntvol+absdirjlink[len(filepath.VolumeName(absdirjlink)):]) - testReadlink(t, ntdirjlinktolink, absdirjlink) - - mklinkj(t, "reldirjlink", "dir") - testReadlink(t, "reldirjlink", dir) // relative directory junction resolves to absolute path - - // Make sure we have sufficient privilege to run mklink command. - testenv.MustHaveSymlink(t) - - absdirlink := filepath.Join(tmpdir, "absdirlink") - mklinkd(t, absdirlink, dir) - testReadlink(t, absdirlink, dir) - - ntdirlink := filepath.Join(tmpdir, "ntdirlink") - mklinkd(t, ntdirlink, ntvol+absdirlink[len(filepath.VolumeName(absdirlink)):]) - testReadlink(t, ntdirlink, absdirlink) - - mklinkd(t, "reldirlink", "dir") - testReadlink(t, "reldirlink", "dir") +func TestReadlink(t *testing.T) { + tests := []struct { + junction bool + dir bool + drive bool + relative bool + }{ + {junction: true, dir: true, drive: true, relative: false}, + {junction: true, dir: true, drive: false, relative: false}, + {junction: true, dir: true, drive: false, relative: true}, + {junction: false, dir: true, drive: true, relative: false}, + {junction: false, dir: true, drive: false, relative: false}, + {junction: false, dir: true, drive: false, relative: true}, + {junction: false, dir: false, drive: true, relative: false}, + {junction: false, dir: false, drive: false, relative: false}, + {junction: false, dir: false, drive: false, relative: true}, + } + for _, tt := range tests { + tt := tt + var name string + if tt.junction { + name = "junction" + } else { + name = "symlink" + } + if tt.dir { + name += "_dir" + } else { + name += "_file" + } + if tt.drive { + name += "_drive" + } else { + name += "_volume" + } + if tt.relative { + name += "_relative" + } else { + name += "_absolute" + } - file := filepath.Join(tmpdir, "file") - err = os.WriteFile(file, []byte(""), 0666) - if err != nil { - t.Fatal(err) + t.Run(name, func(t *testing.T) { + if !tt.relative { + t.Parallel() + } + // Make sure tmpdir is not a symlink, otherwise tests will fail. + tmpdir, err := filepath.EvalSymlinks(t.TempDir()) + if err != nil { + t.Fatal(err) + } + link := filepath.Join(tmpdir, "link") + target := filepath.Join(tmpdir, "target") + if tt.dir { + if err := os.MkdirAll(target, 0777); err != nil { + t.Fatal(err) + } + } else { + if err := os.WriteFile(target, nil, 0666); err != nil { + t.Fatal(err) + } + } + var want string + if tt.relative { + relTarget := filepath.Base(target) + if tt.junction { + want = target // relative directory junction resolves to absolute path + } else { + want = relTarget + } + chdir(t, tmpdir) + link = filepath.Base(link) + target = relTarget + } else { + if tt.drive { + want = target + } else { + volTarget := replaceDriveWithVolumeID(t, target) + if winreadlinkvolume.Value() == "0" { + want = target + } else { + want = volTarget + } + target = volTarget + } + } + if tt.junction { + cmd := testenv.Command(t, "cmd", "/c", "mklink", "/J", link, target) + if out, err := cmd.CombinedOutput(); err != nil { + t.Fatalf("%v: %v\n%s", cmd, err, out) + } + } else { + if err := os.Symlink(target, link); err != nil { + t.Fatalf("Symlink(%#q, %#q): %v", target, link, err) + } + } + got, err := os.Readlink(link) + if err != nil { + t.Fatal(err) + } + if got != want { + t.Fatalf("Readlink(%#q) = %#q; want %#q", target, got, want) + } + }) } - - filelink := filepath.Join(tmpdir, "filelink") - mklink(t, filelink, file) - testReadlink(t, filelink, file) - - linktofilelink := filepath.Join(tmpdir, "linktofilelink") - mklink(t, linktofilelink, ntvol+filelink[len(filepath.VolumeName(filelink)):]) - testReadlink(t, linktofilelink, filelink) - - mklink(t, "relfilelink", "file") - testReadlink(t, "relfilelink", "file") } func TestOpenDirTOCTOU(t *testing.T) { diff --git a/src/path/filepath/path_windows_test.go b/src/path/filepath/path_windows_test.go index 524b0d0f92..2862f390d0 100644 --- a/src/path/filepath/path_windows_test.go +++ b/src/path/filepath/path_windows_test.go @@ -530,6 +530,7 @@ func createMountPartition(t *testing.T, vhd string, args string) []byte { } var winsymlink = godebug.New("winsymlink") +var winreadlinkvolume = godebug.New("winreadlinkvolume") func TestEvalSymlinksJunctionToVolumeID(t *testing.T) { // Test that EvalSymlinks resolves a directory junction which @@ -617,7 +618,11 @@ func TestNTNamespaceSymlink(t *testing.T) { } var want string if winsymlink.Value() == "0" { - want = vol + `\` + if winreadlinkvolume.Value() == "0" { + want = vol + `\` + } else { + want = target + } } else { want = dirlink } @@ -646,7 +651,12 @@ func TestNTNamespaceSymlink(t *testing.T) { if err != nil { t.Fatal(err) } - want = file + + if winreadlinkvolume.Value() == "0" { + want = file + } else { + want = target + } if got != want { t.Errorf(`EvalSymlinks(%q): got %q, want %q`, filelink, got, want) } diff --git a/src/runtime/metrics/doc.go b/src/runtime/metrics/doc.go index 2a1a3055fa..e63599e0d9 100644 --- a/src/runtime/metrics/doc.go +++ b/src/runtime/metrics/doc.go @@ -319,6 +319,10 @@ Below is the full list of supported metrics, ordered lexicographically. The number of non-default behaviors executed by the crypto/tls package due to a non-default GODEBUG=tlsunsafeekm=... setting. + /godebug/non-default-behavior/winreadlinkvolume:events + The number of non-default behaviors executed by the os package + due to a non-default GODEBUG=winreadlinkvolume=... setting. + /godebug/non-default-behavior/winsymlink:events The number of non-default behaviors executed by the os package due to a non-default GODEBUG=winsymlink=... setting. |