workdir presence checks

A container's workdir can be specified via the CLI via `--workdir` and
via an image config with the CLI having precedence.

Since images have a tendency to specify workdirs without necessarily
shipping the paths with the root FS, make sure that Podman creates the
workdir.  When specified via the CLI, do not create the path, but check
for its existence and return a human-friendly error.

NOTE: `crun` is performing a similar check that would yield exit code
127.  With this change, however, Podman performs the check and yields
exit code 126.  Since this is specific to `crun`, I do not consider it
to be a breaking change of Podman.

Fixes: #9040
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

1 files changed, 10 insertions, 2 deletions

diff --git a/pkg/specgen/generate/container_create.go b/pkg/specgen/generate/container_create.go
index 4f36744ca..1bc050b00 100644
--- a/pkg/specgen/generate/container_create.go
+++ b/pkg/specgen/generate/container_create.go
@@ -272,10 +272,18 @@ func createContainerOptions(ctx context.Context, rt *libpod.Runtime, s *specgen.
 	if s.Entrypoint != nil {
 		options = append(options, libpod.WithEntrypoint(s.Entrypoint))
 	}
-	// If the user did not set an workdir but the image did, ensure it is
-	// created.
+	// If the user did not specify a workdir on the CLI, let's extract it
+	// from the image.
 	if s.WorkDir == "" && img != nil {
 		options = append(options, libpod.WithCreateWorkingDir())
+		wd, err := img.WorkingDir(ctx)
+		if err != nil {
+			return nil, err
+		}
+		s.WorkDir = wd
+	}
+	if s.WorkDir == "" {
+		s.WorkDir = "/"
 	}
 	if s.StopSignal != nil {
 		options = append(options, libpod.WithStopSignal(*s.StopSignal))