Enable no_hosts from containers.conf

Since we have no good way to enable this on the server side, we will
just allow it to be set on the client side. This should solve almost all
cases.

Partially fixes: https://github.com/containers/podman/issues/9500

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

4 files changed, 29 insertions, 2 deletions

diff --git a/cmd/podman/common/netflags.go b/cmd/podman/common/netflags.go
index bc4d54de0..4d0a554a6 100644
--- a/cmd/podman/common/netflags.go
+++ b/cmd/podman/common/netflags.go
@@ -80,7 +80,7 @@ func DefineNetFlags(cmd *cobra.Command) {
 	_ = cmd.RegisterFlagCompletionFunc(publishFlagName, completion.AutocompleteNone)
 
 	netFlags.Bool(
-		"no-hosts", false,
+		"no-hosts", containerConfig.Containers.NoHosts,
 		"Do not create /etc/hosts within the container, instead use the version from the image",
 	)
 }
diff --git a/cmd/podman/containers/create.go b/cmd/podman/containers/create.go
index d7507775f..af9278ce1 100644
--- a/cmd/podman/containers/create.go
+++ b/cmd/podman/containers/create.go
@@ -166,7 +166,11 @@ func createInit(c *cobra.Command) error {
 		return errors.Errorf("--cpu-quota and --cpus cannot be set together")
 	}
 
-	if c.Flag("no-hosts").Changed && c.Flag("add-host").Changed {
+	noHosts, err := c.Flags().GetBool("no-hosts")
+	if err != nil {
+		return err
+	}
+	if noHosts && c.Flag("add-host").Changed {
 		return errors.Errorf("--no-hosts and --add-host cannot be set together")
 	}
 	cliVals.UserNS = c.Flag("userns").Value.String()
diff --git a/test/e2e/config/containers.conf b/test/e2e/config/containers.conf
index fdf679664..bbd712254 100644
--- a/test/e2e/config/containers.conf
+++ b/test/e2e/config/containers.conf
@@ -55,6 +55,7 @@ umask = "0002"
 
 annotations=["run.oci.keep_original_groups=1",]
 
+no_hosts=true
 [engine]
 
 network_cmd_options=["allow_host_loopback=true"]
diff --git a/test/e2e/containers_conf_test.go b/test/e2e/containers_conf_test.go
index 9c2260c5f..6b1a0d16e 100644
--- a/test/e2e/containers_conf_test.go
+++ b/test/e2e/containers_conf_test.go
@@ -331,4 +331,26 @@ var _ = Describe("Podman run", func() {
 		Expect(inspect.OutputToString()).To(ContainSubstring("run.oci.keep_original_groups:1"))
 	})
 
+	It("podman run with --add-host and no-hosts=true fails", func() {
+		session := podmanTest.Podman([]string{"run", "-dt", "--add-host", "test1:127.0.0.1", ALPINE, "top"})
+		session.WaitWithDefaultTimeout()
+		Expect(session).To(ExitWithError())
+		Expect(session.ErrorToString()).To(ContainSubstring("--no-hosts and --add-host cannot be set together"))
+
+		session = podmanTest.Podman([]string{"run", "-dt", "--add-host", "test1:127.0.0.1", "--no-hosts=false", ALPINE, "top"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+	})
+
+	It("podman run with no-hosts=true /etc/hosts does not include hostname", func() {
+		session := podmanTest.Podman([]string{"run", "--rm", "--name", "test", ALPINE, "cat", "/etc/hosts"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(session.OutputToString()).To(Not(ContainSubstring("test")))
+
+		session = podmanTest.Podman([]string{"run", "--rm", "--name", "test", "--no-hosts=false", ALPINE, "cat", "/etc/hosts"})
+		session.WaitWithDefaultTimeout()
+		Expect(session.ExitCode()).To(Equal(0))
+		Expect(session.OutputToString()).To(ContainSubstring("test"))
+	})
 })