diff options
Diffstat (limited to 'pkg/sentry/fs/inode_overlay_test.go')
| -rw-r--r-- | pkg/sentry/fs/inode_overlay_test.go | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/pkg/sentry/fs/inode_overlay_test.go b/pkg/sentry/fs/inode_overlay_test.go new file mode 100644 index 000000000..684d54bd2 --- /dev/null +++ b/pkg/sentry/fs/inode_overlay_test.go @@ -0,0 +1,251 @@ +// Copyright 2018 Google Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package fs_test + +import ( + "testing" + + "gvisor.googlesource.com/gvisor/pkg/sentry/context" + "gvisor.googlesource.com/gvisor/pkg/sentry/context/contexttest" + "gvisor.googlesource.com/gvisor/pkg/sentry/fs" + ramfstest "gvisor.googlesource.com/gvisor/pkg/sentry/fs/ramfs/test" + "gvisor.googlesource.com/gvisor/pkg/syserror" +) + +func TestLookup(t *testing.T) { + ctx := contexttest.Context(t) + for _, test := range []struct { + // Test description. + desc string + + // Lookup parameters. + dir *fs.Inode + name string + + // Want from lookup. + err error + found bool + hasUpper bool + hasLower bool + }{ + { + desc: "no upper, lower has name", + dir: fs.NewTestOverlayDir(ctx, + nil, /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: false, + hasLower: true, + }, + { + desc: "no lower, upper has name", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* upper */ + nil, /* lower */ + ), + name: "a", + found: true, + hasUpper: true, + hasLower: false, + }, + { + desc: "upper and lower, only lower has name", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, []dirContent{ + { + name: "b", + dir: false, + }, + }, nil), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: false, + hasLower: true, + }, + { + desc: "upper and lower, only upper has name", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "b", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: true, + hasLower: false, + }, + { + desc: "upper and lower, both have file", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: true, + hasLower: false, + }, + { + desc: "upper and lower, both have directory", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: true, + }, + }, nil), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: true, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: true, + hasLower: true, + }, + { + desc: "upper and lower, upper negative masks lower file", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, nil, []string{"a"}), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: false, + hasUpper: false, + hasLower: false, + }, + { + desc: "upper and lower, upper negative does not mask lower file", + dir: fs.NewTestOverlayDir(ctx, + newTestRamfsDir(ctx, nil, []string{"b"}), /* upper */ + newTestRamfsDir(ctx, []dirContent{ + { + name: "a", + dir: false, + }, + }, nil), /* lower */ + ), + name: "a", + found: true, + hasUpper: false, + hasLower: true, + }, + } { + t.Run(test.desc, func(t *testing.T) { + dirent, err := test.dir.Lookup(ctx, test.name) + if err != test.err { + t.Fatalf("lookup got error %v, want %v", err, test.err) + } + if test.found && dirent.IsNegative() { + t.Fatalf("lookup expected to find %q, got negative dirent", test.name) + } + if !test.found { + return + } + if hasUpper := dirent.Inode.TestHasUpperFS(); hasUpper != test.hasUpper { + t.Fatalf("lookup got upper filesystem %v, want %v", hasUpper, test.hasUpper) + } + if hasLower := dirent.Inode.TestHasLowerFS(); hasLower != test.hasLower { + t.Errorf("lookup got lower filesystem %v, want %v", hasLower, test.hasLower) + } + }) + } +} + +type dir struct { + fs.InodeOperations + + // list of negative child names. + negative []string +} + +func (d *dir) Getxattr(inode *fs.Inode, name string) ([]byte, error) { + for _, n := range d.negative { + if name == fs.XattrOverlayWhiteout(n) { + return []byte("y"), nil + } + } + return nil, syserror.ENOATTR +} + +type dirContent struct { + name string + dir bool +} + +func newTestRamfsDir(ctx context.Context, contains []dirContent, negative []string) *fs.Inode { + msrc := fs.NewCachingMountSource(nil, fs.MountSourceFlags{}) + contents := make(map[string]*fs.Inode) + for _, c := range contains { + if c.dir { + contents[c.name] = newTestRamfsDir(ctx, nil, nil) + } else { + contents[c.name] = fs.NewInode(ramfstest.NewFile(ctx, fs.FilePermissions{}), msrc, fs.StableAttr{Type: fs.RegularFile}) + } + } + dops := ramfstest.NewDir(ctx, contents, fs.FilePermissions{ + User: fs.PermMask{Read: true, Execute: true}, + }) + return fs.NewInode(&dir{ + InodeOperations: dops, + negative: negative, + }, msrc, fs.StableAttr{Type: fs.Directory}) +} |