diff --git a/pkg/ioutils/readers.go b/pkg/ioutils/readers.go index de00b95e3f..e03d3fee75 100644 --- a/pkg/ioutils/readers.go +++ b/pkg/ioutils/readers.go @@ -3,11 +3,15 @@ package ioutils // import "github.com/docker/docker/pkg/ioutils" import ( "context" "io" + "runtime/debug" + "sync/atomic" // make sure crypto.SHA256, crypto.sha512 and crypto.SHA384 are registered // TODO remove once https://github.com/opencontainers/go-digest/pull/64 is merged. _ "crypto/sha256" _ "crypto/sha512" + + "github.com/containerd/log" ) // ReadCloserWrapper wraps an io.Reader, and implements an io.ReadCloser @@ -16,10 +20,15 @@ import ( type ReadCloserWrapper struct { io.Reader closer func() error + closed atomic.Bool } // Close calls back the passed closer function func (r *ReadCloserWrapper) Close() error { + if !r.closed.CompareAndSwap(false, true) { + subsequentCloseWarn("ReadCloserWrapper") + return nil + } return r.closer() } @@ -87,6 +96,7 @@ type cancelReadCloser struct { cancel func() pR *io.PipeReader // Stream to read from pW *io.PipeWriter + closed atomic.Bool } // NewCancelReadCloser creates a wrapper that closes the ReadCloser when the @@ -146,6 +156,17 @@ func (p *cancelReadCloser) closeWithError(err error) { // Close closes the wrapper its underlying reader. It will cause // future calls to Read to return io.EOF. func (p *cancelReadCloser) Close() error { + if !p.closed.CompareAndSwap(false, true) { + subsequentCloseWarn("cancelReadCloser") + return nil + } p.closeWithError(io.EOF) return nil } + +func subsequentCloseWarn(name string) { + log.G(context.TODO()).Error("subsequent attempt to close " + name) + if log.GetLevel() >= log.DebugLevel { + log.G(context.TODO()).Errorf("stack trace: %s", string(debug.Stack())) + } +} diff --git a/pkg/ioutils/writers.go b/pkg/ioutils/writers.go index 61c679497d..1f50602f28 100644 --- a/pkg/ioutils/writers.go +++ b/pkg/ioutils/writers.go @@ -1,6 +1,9 @@ package ioutils // import "github.com/docker/docker/pkg/ioutils" -import "io" +import ( + "io" + "sync/atomic" +) // NopWriter represents a type which write operation is nop. type NopWriter struct{} @@ -29,9 +32,14 @@ func (f *NopFlusher) Flush() {} type writeCloserWrapper struct { io.Writer closer func() error + closed atomic.Bool } func (r *writeCloserWrapper) Close() error { + if !r.closed.CompareAndSwap(false, true) { + subsequentCloseWarn("WriteCloserWrapper") + return nil + } return r.closer() }