Hallyn 2024 03 18 test rmdir (#604)

* feat: test directory removals

Add some tests to make sure when a directory is removed, its
contents are not visible later on.

Signed-off-by: Serge Hallyn <[email protected]>

* test: fix the directory removals test

project-stacker/umoci#6

overlayfs may set 'user.overlay.opaque=y' for deleted directories.
The above PR fixes this handling in our fork of umoci.

Signed-off-by: Ramkumar Chinchani <[email protected]>

---------

Signed-off-by: Serge Hallyn <[email protected]>
Signed-off-by: Ramkumar Chinchani <[email protected]>
Co-authored-by: Serge Hallyn <[email protected]>

go.mod

@@ -285,6 +285,6 @@ require (
 )
 
 replace (
-	github.com/opencontainers/umoci => github.com/project-stacker/umoci v0.0.0-20240223003603-555a0af426e1
+	github.com/opencontainers/umoci => github.com/project-stacker/umoci v0.0.0-20240329154438-26d688b0d7c1
 	stackerbuild.io/stacker-bom => github.com/project-stacker/stacker-bom v0.0.6-0.20240227180605-9a3eb8f7f720
 )

go.sum

@@ -799,8 +799,8 @@ github.com/proglottis/gpgme v0.1.3 h1:Crxx0oz4LKB3QXc5Ea0J19K/3ICfy3ftr5exgUK1AU
 github.com/proglottis/gpgme v0.1.3/go.mod h1:fPbW/EZ0LvwQtH8Hy7eixhp1eF3G39dtx7GUN+0Gmy0=
 github.com/project-stacker/stacker-bom v0.0.6-0.20240227180605-9a3eb8f7f720 h1:7XxHKp0cb8NfDVzZeP+Dgkx4/hdP6bXagwIRcZJNQiw=
 github.com/project-stacker/stacker-bom v0.0.6-0.20240227180605-9a3eb8f7f720/go.mod h1:Z6NhOFXmg2+eBNU77lGAZkiJWyATXix3ZdEJ53Gbkws=
-github.com/project-stacker/umoci v0.0.0-20240223003603-555a0af426e1 h1:TtJDnPCi3mZU56pILbuQbXwmC3EEUJgOSop8NVkAKUE=
-github.com/project-stacker/umoci v0.0.0-20240223003603-555a0af426e1/go.mod h1:XUXUpCpA/Y8aJWezK1i8o4WDR0Y/vhMcWg+FUNQkKMQ=
+github.com/project-stacker/umoci v0.0.0-20240329154438-26d688b0d7c1 h1:7mz6NRnsINUr9yoYLxulCbkz3yFZZu0qZa7Sx8uV1nE=
+github.com/project-stacker/umoci v0.0.0-20240329154438-26d688b0d7c1/go.mod h1:XUXUpCpA/Y8aJWezK1i8o4WDR0Y/vhMcWg+FUNQkKMQ=
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
 github.com/prometheus/client_golang v1.4.0/go.mod h1:e9GMxYsXl05ICDXkRhurwBS4Q3OK1iX/F2sw+iXX5zU=

test/basic.bats

@@ -316,3 +316,77 @@ busybox:
 EOF
     stacker build --substitute "a=b,c" --substitute BUSYBOX_OCI=${BUSYBOX_OCI}
 }
+
+@test "Test whiteouts across layers" {
+    # /aaa is created in l1, removed in l2, re-created in l3
+    # /bbb is created in l2, removed in l3
+    # /ccc is created in l2, removed and recreated in l3
+    # /ddd is created in l1, removed and recreated in l2, and extended in l3
+    cat > stacker.yaml <<"EOF"
+l1:
+    from:
+       type: tar
+       url: .stacker/layer-bases/busybox.tar
+    run: |
+       mkdir -p /aaa/111/ab
+       mkdir -p /ddd/111/ab
+l2:
+    from:
+       type: built
+       tag: l1
+    run: |
+       rm -rf /aaa
+       mkdir -p /bbb/111/ab
+       mkdir -p /ccc/111/ab
+       rm -rf /ddd
+       mkdir -p /ddd/222/ab
+l3:
+    from:
+       type: built
+       tag: l2
+    run: |
+       rm -rf /bbb
+       rm -rf /ccc
+       mkdir -p /aaa/222/ab
+       mkdir -p /ccc/222/ab
+       mkdir -p /ddd/333/ab
+l4:
+    from:
+      type: built
+      tag: l3
+    run: |
+      [ ! -d /aaa/111 ]
+      [ -d /aaa/222/ab ]
+      [ -d /ccc/222 ]
+      [ ! -d /ccc/111 ]
+EOF
+    mkdir -p .stacker/layer-bases
+    chmod 777 .stacker/layer-bases
+    image_copy oci:$BUSYBOX_OCI oci:.stacker/layer-bases/oci:busybox
+    umoci unpack --image .stacker/layer-bases/oci:busybox dest
+    tar caf .stacker/layer-bases/busybox.tar -C dest/rootfs .
+    rm -rf dest
+    # did we really download the image to the right place?
+    [ -f .stacker/layer-bases/busybox.tar ]
+
+    stacker build
+    umoci unpack --image oci:l3 l3
+
+    # aaa/111 should be deleted, aaa/222 should exist
+    [ ! -d l3/rootfs/aaa/111 ]
+    [ -d l3/rootfs/aaa/222/ab ]
+
+    # bbb should be deleted entirely
+    [ ! -d l3/rootfs/bbb ]
+
+    # ccc should be like aaa - but doesn't have an intermediate layer
+    [ -d l3/rootfs/ccc/222 ]
+    [ ! -d l3/rootfs/ccc/111 ]
+
+    # ddd should have both 222 and 333 but not 111
+    # This is to test specifically that the opaque xattr is not copied
+    # up, causing 222 to be missed.
+    [ -d l3/rootfs/ddd/333 ]
+    [ -d l3/rootfs/ddd/222 ]
+    [ ! -d l3/rootfs/ddd/111 ]
+}