oci: Follow the OCI spec for cgroup paths

Getting an absolute path while not having a cgroup mount from the OCI spec is a valid case. In that case the path should be interpreted as a relative one to the system cgroup mount point. Fixes #552 Signed-off-by: Samuel Ortiz <[email protected]>
clearcontainers · Sep 14, 2017 · 6567493 · 6567493
1 parent 876e3fc
commit 6567493
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Showing 2 changed files with 8 additions and 11 deletions.
diff --git a/oci.go b/oci.go
@@ -228,13 +228,9 @@ func processCgroupsPathForResource(ociSpec oci.CompatOCISpec, resource string, i
 	}
 
 	if !cgroupMountFound {
-		if isPod {
-			return "", fmt.Errorf("cgroupsPath %q is absolute, cgroup mount MUST exist",
-				ociSpec.Linux.CgroupsPath)
-		}
-
-		// In case of container (CRI-O), if the mount point is not
-		// provided, we assume this is a relative path.
+		// According to the OCI spec, an absolute path should be
+		// interpreted as relative to the system cgroup mount point
+		// when there is no cgroup mount point.
 		return filepath.Join(cgroupsDirPath, resource, ociSpec.Linux.CgroupsPath), nil
 	}
 

diff --git a/oci_test.go b/oci_test.go
@@ -344,9 +344,10 @@ func TestProcessCgroupsPathRelativePathSuccessful(t *testing.T) {
 	}
 }
 
-func TestProcessCgroupsPathAbsoluteNoCgroupMountFailure(t *testing.T) {
+func TestProcessCgroupsPathAbsoluteNoCgroupMountSuccessful(t *testing.T) {
 	assert := assert.New(t)
 	absoluteCgroupsPath := "/absolute/cgroups/path"
+	cgroupsDirPath = "/foo/runtime/base"
 
 	ociSpec := oci.CompatOCISpec{}
 
@@ -357,9 +358,9 @@ func TestProcessCgroupsPathAbsoluteNoCgroupMountFailure(t *testing.T) {
 	for _, d := range cgroupTestData {
 		ociSpec.Linux.Resources = d.linuxSpec
 
-		_, err := processCgroupsPath(ociSpec, true)
-		assert.Error(err, "This test should fail because no cgroup mount provided (%+v)", d)
-		assert.False(vcMock.IsMockError(err))
+		p := filepath.Join(cgroupsDirPath, d.resource, relativeCgroupsPath)
+
+		testProcessCgroupsPath(t, ociSpec, []string{p})
 	}
 }