From 238abf6e2171f344bbb0ee2233a3e1f6b585ebb0 Mon Sep 17 00:00:00 2001 From: Valentin Rothberg Date: Mon, 7 Sep 2020 11:26:11 +0200 Subject: [PATCH] make image parent check more robust Follow up on issue #7444 and make the parent checks more robust. We can end up with an incoherent storage when, for instance, a build has been killed. Signed-off-by: Valentin Rothberg --- libpod/image/image.go | 13 ++++++++----- libpod/image/layer_tree.go | 4 +++- 2 files changed, 11 insertions(+), 6 deletions(-) diff --git a/libpod/image/image.go b/libpod/image/image.go index dee2ce0eee..2d055cc442 100644 --- a/libpod/image/image.go +++ b/libpod/image/image.go @@ -1247,11 +1247,14 @@ func areParentAndChild(parent, child *imgspecv1.Image) bool { // candidate parent's diff IDs, which together would have // controlled which layers were used - // issue #7444 describes a panic where the length of child.RootFS.DiffIDs - // is checked but child is nil. Adding a simple band-aid approach to prevent - // the problem until the origin of the problem can be worked out in the issue - // itself. - if child == nil || len(parent.RootFS.DiffIDs) > len(child.RootFS.DiffIDs) { + // Both, child and parent, may be nil when the storage is left in an + // incoherent state. Issue #7444 describes such a case when a build + // has been killed. + if child == nil || parent == nil { + return false + } + + if len(parent.RootFS.DiffIDs) > len(child.RootFS.DiffIDs) { return false } childUsesCandidateDiffs := true diff --git a/libpod/image/layer_tree.go b/libpod/image/layer_tree.go index 3699655fde..18101575e6 100644 --- a/libpod/image/layer_tree.go +++ b/libpod/image/layer_tree.go @@ -32,7 +32,9 @@ func (t *layerTree) toOCI(ctx context.Context, i *Image) (*ociv1.Image, error) { oci, exists := t.ociCache[i.ID()] if !exists { oci, err = i.ociv1Image(ctx) - t.ociCache[i.ID()] = oci + if err == nil { + t.ociCache[i.ID()] = oci + } } return oci, err }