copier: add NoOverwriteNonDirDir option

Similar to the `NoOverwriteDirNonDir` one, add an option that disables non-directories from being overwritten by directories. Required-for: containers/podman/issues/14420 Signed-off-by: Valentin Rothberg <[email protected]>
vrothberg · Jun 7, 2022 · 7cc5f19 · 7cc5f19
1 parent b94d4ce
commit 7cc5f19
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Showing 2 changed files with 36 additions and 4 deletions.
diff --git a/copier/copier.go b/copier/copier.go
@@ -344,6 +344,7 @@ type PutOptions struct {
 	IgnoreXattrErrors    bool              // ignore any errors encountered when attempting to set extended attributes
 	IgnoreDevices        bool              // ignore items which are character or block devices
 	NoOverwriteDirNonDir bool              // instead of quietly overwriting directories with non-directories, return an error
+	NoOverwriteNonDirDir bool              // instead of quietly overwriting non-directories with directories, return an error
 	Rename               map[string]string // rename items with the specified names, or under the specified names
 }
 
@@ -1794,12 +1795,15 @@ func copierHandlerPut(bulkReader io.Reader, req request, idMappings *idtools.IDM
 				}
 			case tar.TypeDir:
 				if err = os.Mkdir(path, 0700); err != nil && os.IsExist(err) {
-					var st os.FileInfo
-					if st, err = os.Lstat(path); err == nil && !st.IsDir() {
-						// it's not a directory, so remove it and mkdir
+					if st, stErr := os.Lstat(path); stErr == nil && !st.IsDir() {
+						if req.PutOptions.NoOverwriteNonDirDir {
+							break
+						}
 						if err = os.Remove(path); err == nil {
 							err = os.Mkdir(path, 0700)
 						}
+					} else {
+						err = stErr
 					}
 					// either we removed it and retried, or it was a directory,
 					// in which case we want to just add the new stuff under it

diff --git a/copier/copier_test.go b/copier/copier_test.go
@@ -536,9 +536,10 @@ func testPut(t *testing.T) {
 		}
 	}
 
+	// Overwrite directory
 	for _, overwrite := range []bool{false, true} {
 		for _, typeFlag := range []byte{tar.TypeReg, tar.TypeLink, tar.TypeSymlink, tar.TypeChar, tar.TypeBlock, tar.TypeFifo} {
-			t.Run(fmt.Sprintf("overwrite=%v,type=%c", overwrite, typeFlag), func(t *testing.T) {
+			t.Run(fmt.Sprintf("overwrite (dir)=%v,type=%c", overwrite, typeFlag), func(t *testing.T) {
 				archive := makeArchiveSlice([]tar.Header{
 					{Name: "target", Typeflag: tar.TypeSymlink, Mode: 0755, Linkname: "target", ModTime: testDate},
 					{Name: "target", Typeflag: tar.TypeDir, Mode: 0755, ModTime: testDate},
@@ -563,6 +564,33 @@ func testPut(t *testing.T) {
 		}
 	}
 
+	// Overwrite non-directory
+	for _, overwrite := range []bool{false, true} {
+		for _, typeFlag := range []byte{tar.TypeReg, tar.TypeLink, tar.TypeSymlink, tar.TypeChar, tar.TypeBlock, tar.TypeFifo} {
+			t.Run(fmt.Sprintf("overwrite (non-dir)=%v,type=%c", overwrite, typeFlag), func(t *testing.T) {
+				archive := makeArchiveSlice([]tar.Header{
+					{Name: "target", Typeflag: tar.TypeSymlink, Mode: 0755, Linkname: "target", ModTime: testDate},
+					{Name: "target", Typeflag: tar.TypeReg, Mode: 0755, ModTime: testDate},
+					{Name: "target", Typeflag: tar.TypeSymlink, Mode: 0755, Linkname: "target", ModTime: testDate},
+					{Name: "target", Typeflag: tar.TypeReg, Size: 123, Mode: 0755, ModTime: testDate},
+					{Name: "test", Typeflag: typeFlag, Size: 0, Mode: 0755, Linkname: "target", ModTime: testDate},
+					{Name: "test", Typeflag: tar.TypeDir, Size: 0, Mode: 0755, ModTime: testDate},
+					{Name: "test/content", Typeflag: tar.TypeReg, Size: 0, Mode: 0755, ModTime: testDate},
+				})
+				tmp, err := ioutil.TempDir("", "copier-test-")
+				require.NoErrorf(t, err, "error creating temporary directory")
+				defer os.RemoveAll(tmp)
+				err = Put(tmp, tmp, PutOptions{UIDMap: uidMap, GIDMap: gidMap, NoOverwriteNonDirDir: !overwrite}, bytes.NewReader(archive))
+				if overwrite {
+					if unwrapError(err) != syscall.EPERM {
+						assert.Nilf(t, err, "expected to overwrite file with type %c: %v", typeFlag, err)
+					}
+				} else {
+					assert.Errorf(t, err, "expected an error trying to overwrite file of type %c", typeFlag)
+				}
+			})
+		}
+	}
 	for _, ignoreDevices := range []bool{false, true} {
 		for _, typeFlag := range []byte{tar.TypeChar, tar.TypeBlock} {
 			t.Run(fmt.Sprintf("ignoreDevices=%v,type=%c", ignoreDevices, typeFlag), func(t *testing.T) {