From 1f73374acd3c33d1884e9383205c9f891a3552db Mon Sep 17 00:00:00 2001 From: Paul Holzinger Date: Thu, 3 Jun 2021 16:07:43 +0200 Subject: [PATCH] remote: always send resize before the container starts There is race condition in the remote client attach logic. Because the resize api call was handled in an extra goroutine the container was started before the resize call happend. To fix this we have to call resize in the same goroutine as attach. When the first resize is done start a goroutine to listen on SIGWINCH in the background and resize again if the signal is received. Fixes #9859 Signed-off-by: Paul Holzinger --- pkg/api/handlers/compat/resize.go | 15 ++---- pkg/api/server/register_containers.go | 2 + pkg/bindings/containers/attach.go | 54 ++++++++++--------- .../python/rest_api/fixtures/api_testcase.py | 2 +- .../python/rest_api/test_v2_0_0_container.py | 4 +- test/system/450-interactive.bats | 3 +- 6 files changed, 40 insertions(+), 40 deletions(-) diff --git a/pkg/api/handlers/compat/resize.go b/pkg/api/handlers/compat/resize.go index 23ed33a22c..f65e313fc7 100644 --- a/pkg/api/handlers/compat/resize.go +++ b/pkg/api/handlers/compat/resize.go @@ -46,20 +46,13 @@ func ResizeTTY(w http.ResponseWriter, r *http.Request) { utils.ContainerNotFound(w, name, err) return } - if state, err := ctnr.State(); err != nil { - utils.InternalServerError(w, errors.Wrapf(err, "cannot obtain container state")) - return - } else if state != define.ContainerStateRunning && !query.IgnoreNotRunning { - utils.Error(w, "Container not running", http.StatusConflict, - fmt.Errorf("container %q in wrong state %q", name, state.String())) - return - } - // If container is not running, ignore since this can be a race condition, and is expected if err := ctnr.AttachResize(sz); err != nil { - if errors.Cause(err) != define.ErrCtrStateInvalid || !query.IgnoreNotRunning { + if errors.Cause(err) != define.ErrCtrStateInvalid { utils.InternalServerError(w, errors.Wrapf(err, "cannot resize container")) - return + } else { + utils.Error(w, "Container not running", http.StatusConflict, err) } + return } // This is not a 204, even though we write nothing, for compatibility // reasons. diff --git a/pkg/api/server/register_containers.go b/pkg/api/server/register_containers.go index aa999905e7..88ebb4df5b 100644 --- a/pkg/api/server/register_containers.go +++ b/pkg/api/server/register_containers.go @@ -1364,6 +1364,8 @@ func (s *APIServer) registerContainersHandlers(r *mux.Router) error { // $ref: "#/responses/ok" // 404: // $ref: "#/responses/NoSuchContainer" + // 409: + // $ref: "#/responses/ConflictError" // 500: // $ref: "#/responses/InternalError" r.HandleFunc(VersionedPath("/libpod/containers/{name}/resize"), s.APIHandler(compat.ResizeTTY)).Methods(http.MethodPost) diff --git a/pkg/bindings/containers/attach.go b/pkg/bindings/containers/attach.go index fd8a7011dc..adef1e7c84 100644 --- a/pkg/bindings/containers/attach.go +++ b/pkg/bindings/containers/attach.go @@ -138,7 +138,7 @@ func Attach(ctx context.Context, nameOrID string, stdin io.Reader, stdout io.Wri winCtx, winCancel := context.WithCancel(ctx) defer winCancel() - go attachHandleResize(ctx, winCtx, winChange, false, nameOrID, file) + attachHandleResize(ctx, winCtx, winChange, false, nameOrID, file) } // If we are attaching around a start, we need to "signal" @@ -327,32 +327,38 @@ func (f *rawFormatter) Format(entry *logrus.Entry) ([]byte, error) { return append(buffer, '\r'), nil } -// This is intended to be run as a goroutine, handling resizing for a container -// or exec session. +// This is intended to not be run as a goroutine, handling resizing for a container +// or exec session. It will call resize once and then starts a goroutine which calls resize on winChange func attachHandleResize(ctx, winCtx context.Context, winChange chan os.Signal, isExec bool, id string, file *os.File) { - // Prime the pump, we need one reset to ensure everything is ready - winChange <- sig.SIGWINCH - for { - select { - case <-winCtx.Done(): - return - case <-winChange: - w, h, err := terminal.GetSize(int(file.Fd())) - if err != nil { - logrus.Warnf("failed to obtain TTY size: %v", err) - } + resize := func() { + w, h, err := terminal.GetSize(int(file.Fd())) + if err != nil { + logrus.Warnf("failed to obtain TTY size: %v", err) + } - var resizeErr error - if isExec { - resizeErr = ResizeExecTTY(ctx, id, new(ResizeExecTTYOptions).WithHeight(h).WithWidth(w)) - } else { - resizeErr = ResizeContainerTTY(ctx, id, new(ResizeTTYOptions).WithHeight(h).WithWidth(w)) - } - if resizeErr != nil { - logrus.Warnf("failed to resize TTY: %v", resizeErr) - } + var resizeErr error + if isExec { + resizeErr = ResizeExecTTY(ctx, id, new(ResizeExecTTYOptions).WithHeight(h).WithWidth(w)) + } else { + resizeErr = ResizeContainerTTY(ctx, id, new(ResizeTTYOptions).WithHeight(h).WithWidth(w)) + } + if resizeErr != nil { + logrus.Warnf("failed to resize TTY: %v", resizeErr) } } + + resize() + + go func() { + for { + select { + case <-winCtx.Done(): + return + case <-winChange: + resize() + } + } + }() } // Configure the given terminal for raw mode @@ -457,7 +463,7 @@ func ExecStartAndAttach(ctx context.Context, sessionID string, options *ExecStar winCtx, winCancel := context.WithCancel(ctx) defer winCancel() - go attachHandleResize(ctx, winCtx, winChange, true, sessionID, terminalFile) + attachHandleResize(ctx, winCtx, winChange, true, sessionID, terminalFile) } if options.GetAttachInput() { diff --git a/test/apiv2/python/rest_api/fixtures/api_testcase.py b/test/apiv2/python/rest_api/fixtures/api_testcase.py index 8b771774b7..155e939282 100644 --- a/test/apiv2/python/rest_api/fixtures/api_testcase.py +++ b/test/apiv2/python/rest_api/fixtures/api_testcase.py @@ -49,7 +49,7 @@ def tearDownClass(cls): def setUp(self): super().setUp() - APITestCase.podman.run("run", "alpine", "/bin/ls", check=True) + APITestCase.podman.run("run", "-d", "alpine", "top", check=True) def tearDown(self) -> None: APITestCase.podman.run("pod", "rm", "--all", "--force", check=True) diff --git a/test/apiv2/python/rest_api/test_v2_0_0_container.py b/test/apiv2/python/rest_api/test_v2_0_0_container.py index f670131174..b4b3af2df6 100644 --- a/test/apiv2/python/rest_api/test_v2_0_0_container.py +++ b/test/apiv2/python/rest_api/test_v2_0_0_container.py @@ -12,7 +12,7 @@ def test_list(self): r = requests.get(self.uri("/containers/json"), timeout=5) self.assertEqual(r.status_code, 200, r.text) obj = r.json() - self.assertEqual(len(obj), 0) + self.assertEqual(len(obj), 1) def test_list_all(self): r = requests.get(self.uri("/containers/json?all=true")) @@ -36,7 +36,7 @@ def test_stats(self): self.assertId(r.content) def test_delete(self): - r = requests.delete(self.uri(self.resolve_container("/containers/{}"))) + r = requests.delete(self.uri(self.resolve_container("/containers/{}?force=true"))) self.assertEqual(r.status_code, 204, r.text) def test_stop(self): diff --git a/test/system/450-interactive.bats b/test/system/450-interactive.bats index a9bf52ee8c..a2db39492c 100644 --- a/test/system/450-interactive.bats +++ b/test/system/450-interactive.bats @@ -56,8 +56,7 @@ function teardown() { stty rows $rows cols $cols <$PODMAN_TEST_PTY # ...and make sure stty under podman reads that. - # FIXME: 'sleep 1' is needed for podman-remote; without it, there's - run_podman run -it --name mystty $IMAGE sh -c 'sleep 1;stty size' <$PODMAN_TEST_PTY + run_podman run -it --name mystty $IMAGE stty size <$PODMAN_TEST_PTY is "$output" "$rows $cols" "stty under podman reads the correct dimensions" }