Merge pull request #55018 from dims/use-real-bash-not-dash

Automatic merge from submit-queue (batch tested with PRs 56497, 56500, 55018, 56544, 56425). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Do not fake /bin/bash, just use the real bash

**What this PR does / why we need it**:

Looks like 0.6, we ended up with dash as the default shell, with
/bin/sh as well as /bin/dash ending up invoking dash.

We should not change the contract by faking a link to /bin/bash.
Let's install the actual bash package and make sure /bin/sh is
linked to /bin/bash as well.


**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #55012

**Special notes for your reviewer**:

**Release note**:

```release-note
Fix problem with /bin/bash ending up linked to dash 
```

build/debian-hyperkube-base/Dockerfile

@@ -14,10 +14,13 @@
 
 FROM BASEIMAGE
 
+RUN echo CACHEBUST>/dev/null && clean-install \
+    bash
+
 # The samba-common, cifs-utils, and nfs-common packages depend on
-# ucf, which itself depends on /bin/bash existing.
-# It doesn't seem to actually need bash, however.
-RUN ln -s /bin/sh /bin/bash
+# ucf, which itself depends on /bin/bash.
+RUN echo "dash dash/sh boolean false" | debconf-set-selections
+RUN DEBIAN_FRONTEND=noninteractive dpkg-reconfigure dash
 
 RUN echo CACHEBUST>/dev/null && clean-install \
     ca-certificates \

build/debian-hyperkube-base/Makefile

@@ -19,7 +19,7 @@
 
 REGISTRY?=gcr.io/google-containers
 IMAGE?=debian-hyperkube-base
-TAG=0.7
+TAG=0.8
 ARCH?=amd64
 CACHEBUST?=1
 

build/root/WORKSPACE

@@ -88,10 +88,10 @@ docker_pull(
 
 docker_pull(
     name = "debian-hyperkube-base-amd64",
-    digest = "sha256:1a05a58432254268c31ef5c8d9c21f3d01a40611b14707de6ac2772c0793bd13",
+    digest = "sha256:fc1b461367730660ac5a40c1eb2d1b23221829acf8a892981c12361383b3742b",
     registry = "gcr.io",
     repository = "google-containers/debian-hyperkube-base-amd64",
-    tag = "0.7",  # ignored, but kept here for documentation
+    tag = "0.8",  # ignored, but kept here for documentation
 )
 
 docker_pull(

cluster/images/hyperkube/Makefile

@@ -21,7 +21,7 @@ REGISTRY?=gcr.io/google-containers
 ARCH?=amd64
 HYPERKUBE_BIN?=_output/dockerized/bin/linux/$(ARCH)/hyperkube
 
-BASEIMAGE=gcr.io/google-containers/debian-hyperkube-base-$(ARCH):0.7
+BASEIMAGE=gcr.io/google-containers/debian-hyperkube-base-$(ARCH):0.8
 TEMP_DIR:=$(shell mktemp -d -t hyperkubeXXXXXX)
 
 all: build