podman build: pass runtime to buildah

Make sure that Podman's default OCI runtime is passed to Buildah in
`podman build`.  In theory, Podman and Buildah should use the same
defaults but the projects move at different speeds and it turns out
we caused a regression in v3.0.

Fixes: #9365
Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

2 files changed, 30 insertions, 0 deletions

diff --git a/libpod/runtime_img.go b/libpod/runtime_img.go
index f56fa8cce..fcc52b392 100644
--- a/libpod/runtime_img.go
+++ b/libpod/runtime_img.go
@@ -166,6 +166,11 @@ func (r *Runtime) newImageBuildCompleteEvent(idOrName string) {
 
 // Build adds the runtime to the imagebuildah call
 func (r *Runtime) Build(ctx context.Context, options imagebuildah.BuildOptions, dockerfiles ...string) (string, reference.Canonical, error) {
+	if options.Runtime == "" {
+		// Make sure that build containers use the same runtime as Podman (see #9365).
+		conf := util.DefaultContainerConfig()
+		options.Runtime = conf.Engine.OCIRuntime
+	}
 	id, ref, err := imagebuildah.BuildDockerfiles(ctx, r.store, options, dockerfiles...)
 	// Write event for build completion
 	r.newImageBuildCompleteEvent(id)
diff --git a/test/system/070-build.bats b/test/system/070-build.bats
index 7a42a4c18..c18f3f7a7 100644
--- a/test/system/070-build.bats
+++ b/test/system/070-build.bats
@@ -46,6 +46,31 @@ EOF
     is "$output" ".*invalidflag" "failed when passing undefined flags to the runtime"
 }
 
+@test "podman build - set runtime" {
+    skip_if_remote "--runtime flag not supported for remote"
+    # Test on the CLI and via containers.conf
+
+    tmpdir=$PODMAN_TMPDIR/build-test
+    run mkdir -p $tmpdir
+    containerfile=$tmpdir/Containerfile
+    cat >$containerfile <<EOF
+FROM $IMAGE
+RUN echo $rand_content
+EOF
+
+    run_podman 125 --runtime=idonotexist build -t build_test $tmpdir
+    is "$output" ".*\"idonotexist\" not found.*" "failed when passing invalid OCI runtime via CLI"
+
+    containersconf=$tmpdir/containers.conf
+    cat >$containersconf <<EOF
+[engine]
+runtime="idonotexist"
+EOF
+
+    CONTAINERS_CONF="$containersconf" run_podman 125 build -t build_test $tmpdir
+    is "$output" ".*\"idonotexist\" not found.*" "failed when passing invalid OCI runtime via containers.conf"
+}
+
 # Regression from v1.5.0. This test passes fine in v1.5.0, fails in 1.6
 @test "podman build - cache (#3920)" {
     # Make an empty test directory, with a subdirectory used for tar