diff options
| -rw-r--r-- | pkg/sentry/fs/ext/BUILD | 1 | ||||
| -rw-r--r-- | pkg/sentry/fs/ext/ext_test.go | 103 |
2 files changed, 104 insertions, 0 deletions
diff --git a/pkg/sentry/fs/ext/BUILD b/pkg/sentry/fs/ext/BUILD index c6168da0a..64dc288c8 100644 --- a/pkg/sentry/fs/ext/BUILD +++ b/pkg/sentry/fs/ext/BUILD @@ -76,6 +76,7 @@ go_test( "//pkg/sentry/context/contexttest", "//pkg/sentry/fs/ext/disklayout", "//pkg/sentry/kernel/auth", + "//pkg/sentry/usermem", "//pkg/sentry/vfs", "//runsc/test/testutil", "@com_github_google_go-cmp//cmp:go_default_library", diff --git a/pkg/sentry/fs/ext/ext_test.go b/pkg/sentry/fs/ext/ext_test.go index f177dbd47..0b8311544 100644 --- a/pkg/sentry/fs/ext/ext_test.go +++ b/pkg/sentry/fs/ext/ext_test.go @@ -16,6 +16,7 @@ package ext import ( "fmt" + "io" "os" "path" "sort" @@ -27,6 +28,7 @@ import ( "gvisor.dev/gvisor/pkg/sentry/context/contexttest" "gvisor.dev/gvisor/pkg/sentry/fs/ext/disklayout" "gvisor.dev/gvisor/pkg/sentry/kernel/auth" + "gvisor.dev/gvisor/pkg/sentry/usermem" "gvisor.dev/gvisor/pkg/sentry/vfs" "gvisor.dev/gvisor/runsc/test/testutil" @@ -80,6 +82,107 @@ func setUp(t *testing.T, imagePath string) (context.Context, *vfs.VirtualFilesys return ctx, vfsObj, &root, tearDown, nil } +// TestRead tests the read functionality for vfs file descriptions. +func TestRead(t *testing.T) { + type readTest struct { + name string + image string + absPath string + } + + tests := []readTest{ + { + name: "ext4 read small file", + image: ext4ImagePath, + absPath: "/file.txt", + }, + { + name: "ext3 read small file", + image: ext3ImagePath, + absPath: "/file.txt", + }, + { + name: "ext2 read small file", + image: ext2ImagePath, + absPath: "/file.txt", + }, + { + name: "ext4 read big file", + image: ext4ImagePath, + absPath: "/bigfile.txt", + }, + { + name: "ext3 read big file", + image: ext3ImagePath, + absPath: "/bigfile.txt", + }, + { + name: "ext2 read big file", + image: ext2ImagePath, + absPath: "/bigfile.txt", + }, + } + + for _, test := range tests { + t.Run(test.name, func(t *testing.T) { + ctx, vfsfs, root, tearDown, err := setUp(t, test.image) + if err != nil { + t.Fatalf("setUp failed: %v", err) + } + defer tearDown() + + fd, err := vfsfs.OpenAt( + ctx, + auth.CredentialsFromContext(ctx), + &vfs.PathOperation{Root: *root, Start: *root, Pathname: test.absPath}, + &vfs.OpenOptions{}, + ) + if err != nil { + t.Fatalf("vfsfs.OpenAt failed: %v", err) + } + + // Get a local file descriptor and compare its functionality with a vfs file + // description for the same file. + localFile, err := testutil.FindFile(path.Join(assetsDir, test.absPath)) + if err != nil { + t.Fatalf("testutil.FindFile failed for %s: %v", test.absPath, err) + } + + f, err := os.Open(localFile) + if err != nil { + t.Fatalf("os.Open failed for %s: %v", localFile, err) + } + defer f.Close() + + // Read the entire file by reading one byte repeatedly. Doing this stress + // tests the underlying file reader implementation. + got := make([]byte, 1) + want := make([]byte, 1) + for { + n, err := f.Read(want) + fd.Impl().Read(ctx, usermem.BytesIOSequence(got), vfs.ReadOptions{}) + + if diff := cmp.Diff(got, want); diff != "" { + t.Errorf("file data mismatch (-want +got):\n%s", diff) + } + + // Make sure there is no more file data left after getting EOF. + if n == 0 || err == io.EOF { + if n, _ := fd.Impl().Read(ctx, usermem.BytesIOSequence(got), vfs.ReadOptions{}); n != 0 { + t.Errorf("extra unexpected file data in file %s in image %s", test.absPath, test.image) + } + + break + } + + if err != nil { + t.Fatalf("read failed: %v", err) + } + } + }) + } +} + // iterDirentsCb is a simple callback which just keeps adding the dirents to an // internal list. Implements vfs.IterDirentsCallback. type iterDirentsCb struct { |