Remove resize race condition

Since podman-remote resize requests can come in at random times, this
generates a real potential for race conditions. We should only be
attempting to resize TTY on running containers, but the containers can
go from running to stopped at any time, and returning an error to the
caller is just causing noice.

This change will basically ignore requests to resize terminals if the
container is not running and return the caller to success.  All other
callers will still return failure.

Fixes: https://github.com/containers/podman/issues/9831

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

1 files changed, 14 insertions, 8 deletions

diff --git a/pkg/api/handlers/compat/resize.go b/pkg/api/handlers/compat/resize.go
index 1bf7ad460..23ed33a22 100644
--- a/pkg/api/handlers/compat/resize.go
+++ b/pkg/api/handlers/compat/resize.go
@@ -19,8 +19,9 @@ func ResizeTTY(w http.ResponseWriter, r *http.Request) {
 
 	// /containers/{id}/resize
 	query := struct {
-		Height uint16 `schema:"h"`
-		Width  uint16 `schema:"w"`
+		Height           uint16 `schema:"h"`
+		Width            uint16 `schema:"w"`
+		IgnoreNotRunning bool   `schema:"running"`
 	}{
 		// override any golang type defaults
 	}
@@ -48,14 +49,17 @@ func ResizeTTY(w http.ResponseWriter, r *http.Request) {
 		if state, err := ctnr.State(); err != nil {
 			utils.InternalServerError(w, errors.Wrapf(err, "cannot obtain container state"))
 			return
-		} else if state != define.ContainerStateRunning {
+		} 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 {
-			utils.InternalServerError(w, errors.Wrapf(err, "cannot resize container"))
-			return
+			if errors.Cause(err) != define.ErrCtrStateInvalid || !query.IgnoreNotRunning {
+				utils.InternalServerError(w, errors.Wrapf(err, "cannot resize container"))
+				return
+			}
 		}
 		// This is not a 204, even though we write nothing, for compatibility
 		// reasons.
@@ -70,14 +74,16 @@ func ResizeTTY(w http.ResponseWriter, r *http.Request) {
 		if state, err := ctnr.State(); err != nil {
 			utils.InternalServerError(w, errors.Wrapf(err, "cannot obtain session container state"))
 			return
-		} else if state != define.ContainerStateRunning {
+		} 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 err := ctnr.ExecResize(name, sz); err != nil {
-			utils.InternalServerError(w, errors.Wrapf(err, "cannot resize session"))
-			return
+			if errors.Cause(err) != define.ErrCtrStateInvalid || !query.IgnoreNotRunning {
+				utils.InternalServerError(w, errors.Wrapf(err, "cannot resize session"))
+				return
+			}
 		}
 		// This is not a 204, even though we write nothing, for compatibility
 		// reasons.