check for context canceled after competing for locks (#13239)

once we have competed for locks, verify if the
context is still valid - this is to ensure that
we do not start readdir() or read() calls on the
drives on canceled connections.

cmd/api-errors.go

@@ -1787,12 +1787,10 @@ func toAPIErrorCode(ctx context.Context, err error) (apiErr APIErrorCode) {
 
 	// Only return ErrClientDisconnected if the provided context is actually canceled.
 	// This way downstream context.Canceled will still report ErrOperationTimedOut
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		if ctx.Err() == context.Canceled {
 			return ErrClientDisconnected
 		}
-	default:
 	}
 
 	switch err {

cmd/metacache-set.go

@@ -351,10 +351,8 @@ func (er *erasureObjects) streamMetadataParts(ctx context.Context, o listPathOpt
 	rpc := globalNotificationSys.restClientFromHash(o.Bucket)
 
 	for {
-		select {
+		if contextCanceled(ctx) {
-		case <-ctx.Done():
 			return entries, ctx.Err()
-		default:
 		}
 
 		// If many failures, check the cache state.
@@ -424,10 +422,8 @@ func (er *erasureObjects) streamMetadataParts(ctx context.Context, o listPathOpt
 		// We got a stream to start at.
 		loadedPart := 0
 		for {
-			select {
+			if contextCanceled(ctx) {
-			case <-ctx.Done():
 				return entries, ctx.Err()
-			default:
 			}
 
 			if partN != loadedPart {

cmd/metacache-walk.go

@@ -87,7 +87,7 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 	// Fast exit track to check if we are listing an object with
 	// a trailing slash, this will avoid to list the object content.
 	if HasSuffix(opts.BaseDir, SlashSeparator) {
-		metadata, err := s.readMetadata(pathJoin(volumeDir,
+		metadata, err := s.readMetadata(ctx, pathJoin(volumeDir,
 			opts.BaseDir[:len(opts.BaseDir)-1]+globalDirSuffix,
 			xlStorageFormatFile))
 		if err == nil {
@@ -175,7 +175,7 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 			if HasSuffix(entry, xlStorageFormatFile) {
 				var meta metaCacheEntry
 				s.walkReadMu.Lock()
-				meta.metadata, err = s.readMetadata(pathJoin(volumeDir, current, entry))
+				meta.metadata, err = s.readMetadata(ctx, pathJoin(volumeDir, current, entry))
 				s.walkReadMu.Unlock()
 				if err != nil {
 					logger.LogIf(ctx, err)
@@ -250,7 +250,7 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 			}
 
 			s.walkReadMu.Lock()
-			meta.metadata, err = s.readMetadata(pathJoin(volumeDir, meta.name, xlStorageFormatFile))
+			meta.metadata, err = s.readMetadata(ctx, pathJoin(volumeDir, meta.name, xlStorageFormatFile))
 			s.walkReadMu.Unlock()
 			switch {
 			case err == nil:
@@ -300,9 +300,15 @@ func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writ
 
 func (p *xlStorageDiskIDCheck) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) error {
 	defer p.updateStorageMetrics(storageMetricWalkDir, opts.Bucket, opts.BaseDir)()
+
+	if contextCanceled(ctx) {
+		return ctx.Err()
+	}
+
 	if err := p.checkDiskStale(); err != nil {
 		return err
 	}
+
 	return p.storage.WalkDir(ctx, opts, wr)
 }
 

cmd/xl-storage-disk-id-check.go

@@ -159,10 +159,8 @@ func (p *xlStorageDiskIDCheck) Healing() *healingTracker {
 }
 
 func (p *xlStorageDiskIDCheck) NSScanner(ctx context.Context, cache dataUsageCache, updates chan<- dataUsageEntry) (dataUsageCache, error) {
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return dataUsageCache{}, ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -210,10 +208,8 @@ func (p *xlStorageDiskIDCheck) checkDiskStale() error {
 }
 
 func (p *xlStorageDiskIDCheck) DiskInfo(ctx context.Context) (info DiskInfo, err error) {
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return DiskInfo{}, ctx.Err()
-	default:
 	}
 
 	info, err = p.storage.DiskInfo(ctx)
@@ -235,10 +231,8 @@ func (p *xlStorageDiskIDCheck) DiskInfo(ctx context.Context) (info DiskInfo, err
 func (p *xlStorageDiskIDCheck) MakeVolBulk(ctx context.Context, volumes ...string) (err error) {
 	defer p.updateStorageMetrics(storageMetricMakeVolBulk, volumes...)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -250,10 +244,8 @@ func (p *xlStorageDiskIDCheck) MakeVolBulk(ctx context.Context, volumes ...strin
 func (p *xlStorageDiskIDCheck) MakeVol(ctx context.Context, volume string) (err error) {
 	defer p.updateStorageMetrics(storageMetricMakeVol, volume)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -265,10 +257,8 @@ func (p *xlStorageDiskIDCheck) MakeVol(ctx context.Context, volume string) (err
 func (p *xlStorageDiskIDCheck) ListVols(ctx context.Context) ([]VolInfo, error) {
 	defer p.updateStorageMetrics(storageMetricListVols, "/")()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return nil, ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -280,10 +270,8 @@ func (p *xlStorageDiskIDCheck) ListVols(ctx context.Context) ([]VolInfo, error)
 func (p *xlStorageDiskIDCheck) StatVol(ctx context.Context, volume string) (vol VolInfo, err error) {
 	defer p.updateStorageMetrics(storageMetricStatVol, volume)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return VolInfo{}, ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -295,10 +283,8 @@ func (p *xlStorageDiskIDCheck) StatVol(ctx context.Context, volume string) (vol
 func (p *xlStorageDiskIDCheck) DeleteVol(ctx context.Context, volume string, forceDelete bool) (err error) {
 	defer p.updateStorageMetrics(storageMetricDeleteVol, volume)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -310,10 +296,8 @@ func (p *xlStorageDiskIDCheck) DeleteVol(ctx context.Context, volume string, for
 func (p *xlStorageDiskIDCheck) ListDir(ctx context.Context, volume, dirPath string, count int) ([]string, error) {
 	defer p.updateStorageMetrics(storageMetricListDir, volume, dirPath)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return nil, ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -326,10 +310,8 @@ func (p *xlStorageDiskIDCheck) ListDir(ctx context.Context, volume, dirPath stri
 func (p *xlStorageDiskIDCheck) ReadFile(ctx context.Context, volume string, path string, offset int64, buf []byte, verifier *BitrotVerifier) (n int64, err error) {
 	defer p.updateStorageMetrics(storageMetricReadFile, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return 0, ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -342,10 +324,8 @@ func (p *xlStorageDiskIDCheck) ReadFile(ctx context.Context, volume string, path
 func (p *xlStorageDiskIDCheck) AppendFile(ctx context.Context, volume string, path string, buf []byte) (err error) {
 	defer p.updateStorageMetrics(storageMetricAppendFile, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -358,10 +338,8 @@ func (p *xlStorageDiskIDCheck) AppendFile(ctx context.Context, volume string, pa
 func (p *xlStorageDiskIDCheck) CreateFile(ctx context.Context, volume, path string, size int64, reader io.Reader) error {
 	defer p.updateStorageMetrics(storageMetricCreateFile, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -374,10 +352,8 @@ func (p *xlStorageDiskIDCheck) CreateFile(ctx context.Context, volume, path stri
 func (p *xlStorageDiskIDCheck) ReadFileStream(ctx context.Context, volume, path string, offset, length int64) (io.ReadCloser, error) {
 	defer p.updateStorageMetrics(storageMetricReadFileStream, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return nil, ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -390,10 +366,8 @@ func (p *xlStorageDiskIDCheck) ReadFileStream(ctx context.Context, volume, path
 func (p *xlStorageDiskIDCheck) RenameFile(ctx context.Context, srcVolume, srcPath, dstVolume, dstPath string) error {
 	defer p.updateStorageMetrics(storageMetricRenameFile, srcVolume, srcPath, dstVolume, dstPath)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -406,10 +380,8 @@ func (p *xlStorageDiskIDCheck) RenameFile(ctx context.Context, srcVolume, srcPat
 func (p *xlStorageDiskIDCheck) RenameData(ctx context.Context, srcVolume, srcPath string, fi FileInfo, dstVolume, dstPath string) error {
 	defer p.updateStorageMetrics(storageMetricRenameData, srcPath, fi.DataDir, dstVolume, dstPath)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -422,10 +394,8 @@ func (p *xlStorageDiskIDCheck) RenameData(ctx context.Context, srcVolume, srcPat
 func (p *xlStorageDiskIDCheck) CheckParts(ctx context.Context, volume string, path string, fi FileInfo) (err error) {
 	defer p.updateStorageMetrics(storageMetricCheckParts, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -438,10 +408,8 @@ func (p *xlStorageDiskIDCheck) CheckParts(ctx context.Context, volume string, pa
 func (p *xlStorageDiskIDCheck) Delete(ctx context.Context, volume string, path string, recursive bool) (err error) {
 	defer p.updateStorageMetrics(storageMetricDelete, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -464,13 +432,11 @@ func (p *xlStorageDiskIDCheck) DeleteVersions(ctx context.Context, volume string
 
 	errs = make([]error, len(versions))
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		for i := range errs {
 			errs[i] = ctx.Err()
 		}
 		return errs
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -486,10 +452,8 @@ func (p *xlStorageDiskIDCheck) DeleteVersions(ctx context.Context, volume string
 func (p *xlStorageDiskIDCheck) VerifyFile(ctx context.Context, volume, path string, fi FileInfo) error {
 	defer p.updateStorageMetrics(storageMetricVerifyFile, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err := p.checkDiskStale(); err != nil {
@@ -502,10 +466,8 @@ func (p *xlStorageDiskIDCheck) VerifyFile(ctx context.Context, volume, path stri
 func (p *xlStorageDiskIDCheck) WriteAll(ctx context.Context, volume string, path string, b []byte) (err error) {
 	defer p.updateStorageMetrics(storageMetricWriteAll, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -518,10 +480,8 @@ func (p *xlStorageDiskIDCheck) WriteAll(ctx context.Context, volume string, path
 func (p *xlStorageDiskIDCheck) DeleteVersion(ctx context.Context, volume, path string, fi FileInfo, forceDelMarker bool) (err error) {
 	defer p.updateStorageMetrics(storageMetricDeleteVersion, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -534,10 +494,8 @@ func (p *xlStorageDiskIDCheck) DeleteVersion(ctx context.Context, volume, path s
 func (p *xlStorageDiskIDCheck) UpdateMetadata(ctx context.Context, volume, path string, fi FileInfo) (err error) {
 	defer p.updateStorageMetrics(storageMetricUpdateMetadata, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -550,10 +508,8 @@ func (p *xlStorageDiskIDCheck) UpdateMetadata(ctx context.Context, volume, path
 func (p *xlStorageDiskIDCheck) WriteMetadata(ctx context.Context, volume, path string, fi FileInfo) (err error) {
 	defer p.updateStorageMetrics(storageMetricWriteMetadata, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -566,10 +522,8 @@ func (p *xlStorageDiskIDCheck) WriteMetadata(ctx context.Context, volume, path s
 func (p *xlStorageDiskIDCheck) ReadVersion(ctx context.Context, volume, path, versionID string, readData bool) (fi FileInfo, err error) {
 	defer p.updateStorageMetrics(storageMetricReadVersion, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return fi, ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -582,10 +536,8 @@ func (p *xlStorageDiskIDCheck) ReadVersion(ctx context.Context, volume, path, ve
 func (p *xlStorageDiskIDCheck) ReadAll(ctx context.Context, volume string, path string) (buf []byte, err error) {
 	defer p.updateStorageMetrics(storageMetricReadAll, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return nil, ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {
@@ -598,10 +550,8 @@ func (p *xlStorageDiskIDCheck) ReadAll(ctx context.Context, volume string, path
 func (p *xlStorageDiskIDCheck) StatInfoFile(ctx context.Context, volume, path string) (stat StatInfo, err error) {
 	defer p.updateStorageMetrics(storageStatInfoFile, volume, path)()
 
-	select {
+	if contextCanceled(ctx) {
-	case <-ctx.Done():
 		return StatInfo{}, ctx.Err()
-	default:
 	}
 
 	if err = p.checkDiskStale(); err != nil {

cmd/xl-storage.go

@@ -397,7 +397,11 @@ func (s *xlStorage) Healing() *healingTracker {
 	return &h
 }
 
-func (s *xlStorage) readMetadata(itemPath string) ([]byte, error) {
+func (s *xlStorage) readMetadata(ctx context.Context, itemPath string) ([]byte, error) {
+	if contextCanceled(ctx) {
+		return nil, ctx.Err()
+	}
+
 	if err := checkPathLength(itemPath); err != nil {
 		return nil, err
 	}
@@ -468,7 +472,7 @@ func (s *xlStorage) NSScanner(ctx context.Context, cache dataUsageCache, updates
 			return sizeSummary{}, errSkipFile
 		}
 
-		buf, err := s.readMetadata(item.Path)
+		buf, err := s.readMetadata(ctx, item.Path)
 		if err != nil {
 			if intDataUpdateTracker.debug {
 				console.Debugf(color.Green("scannerBucket:")+" object path missing: %v: %w\n", item.Path, err)
@@ -791,6 +795,10 @@ func (s *xlStorage) DeleteVol(ctx context.Context, volume string, forceDelete bo
 // ListDir - return all the entries at the given directory path.
 // If an entry is a directory it will be returned with a trailing SlashSeparator.
 func (s *xlStorage) ListDir(ctx context.Context, volume, dirPath string, count int) (entries []string, err error) {
+	if contextCanceled(ctx) {
+		return nil, ctx.Err()
+	}
+
 	// Verify if volume is valid and it exists.
 	volumeDir, err := s.getVolDir(volume)
 	if err != nil {
@@ -1090,7 +1098,7 @@ func (s *xlStorage) ReadVersion(ctx context.Context, volume, path, versionID str
 	if readData {
 		buf, err = s.ReadAll(ctx, volume, pathJoin(path, xlStorageFormatFile))
 	} else {
-		buf, err = s.readMetadata(pathJoin(volumeDir, path, xlStorageFormatFile))
+		buf, err = s.readMetadata(ctx, pathJoin(volumeDir, path, xlStorageFormatFile))
 		if err != nil {
 			if osIsNotExist(err) {
 				if err = Access(volumeDir); err != nil && osIsNotExist(err) {

cmd/xl-storage_test.go

@@ -1834,7 +1834,7 @@ func TestXLStorageReadMetadata(t *testing.T) {
 	}
 
 	disk.MakeVol(context.Background(), volume)
-	if _, err := disk.readMetadata(pathJoin(tmpDir, volume, object)); err != errFileNameTooLong {
+	if _, err := disk.readMetadata(context.Background(), pathJoin(tmpDir, volume, object)); err != errFileNameTooLong {
 		t.Fatalf("Unexpected error from readMetadata - expect %v: got %v", errFileNameTooLong, err)
 	}
 }