In shared networkNS /etc/resolv.conf&/etc/hosts should be shared

We should just bind mount the original containers /etc/resolv.conf and /etchosts
into the new container.  Changes in the resolv.conf and hosts should be seen
by all containers,  This matches Docker behaviour.

In order to make this work the labels on these files need to have a shared
SELinux label.

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

1 files changed, 12 insertions, 13 deletions

diff --git a/libpod/container_internal_linux.go b/libpod/container_internal_linux.go
index 86f94477e..3c0c5c3cf 100644
--- a/libpod/container_internal_linux.go
+++ b/libpod/container_internal_linux.go
@@ -26,7 +26,6 @@ import (
 	"github.com/containers/libpod/pkg/rootless"
 	"github.com/containers/libpod/pkg/secrets"
 	"github.com/containers/storage/pkg/idtools"
-	"github.com/mrunalp/fileutils"
 	"github.com/opencontainers/runc/libcontainer/user"
 	spec "github.com/opencontainers/runtime-spec/specs-go"
 	"github.com/opencontainers/runtime-tools/generate"
@@ -677,20 +676,12 @@ func (c *Container) makeBindMounts() error {
 			// If it doesn't, don't copy them
 			resolvPath, exists := bindMounts["/etc/resolv.conf"]
 			if exists {
-				resolvDest := filepath.Join(c.state.RunDir, "resolv.conf")
-				if err := fileutils.CopyFile(resolvPath, resolvDest); err != nil {
-					return errors.Wrapf(err, "error copying resolv.conf from dependency container %s of container %s", depCtr.ID(), c.ID())
-				}
-				c.state.BindMounts["/etc/resolv.conf"] = resolvDest
-			}
 
+				c.state.BindMounts["/etc/resolv.conf"] = resolvPath
+			}
 			hostsPath, exists := bindMounts["/etc/hosts"]
 			if exists {
-				hostsDest := filepath.Join(c.state.RunDir, "hosts")
-				if err := fileutils.CopyFile(hostsPath, hostsDest); err != nil {
-					return errors.Wrapf(err, "error copying hosts file from dependency container %s of container %s", depCtr.ID(), c.ID())
-				}
-				c.state.BindMounts["/etc/hosts"] = hostsDest
+				c.state.BindMounts["/etc/hosts"] = hostsPath
 			}
 		} else {
 			newResolv, err := c.generateResolvConf()
@@ -705,6 +696,14 @@ func (c *Container) makeBindMounts() error {
 			}
 			c.state.BindMounts["/etc/hosts"] = newHosts
 		}
+
+		if err := label.Relabel(c.state.BindMounts["/etc/hosts"], c.config.MountLabel, true); err != nil {
+			return err
+		}
+
+		if err := label.Relabel(c.state.BindMounts["/etc/resolv.conf"], c.config.MountLabel, true); err != nil {
+			return err
+		}
 	}
 
 	// SHM is always added when we mount the container
@@ -809,7 +808,7 @@ func (c *Container) generateResolvConf() (string, error) {
 	}
 
 	// Relabel resolv.conf for the container
-	if err := label.Relabel(destPath, c.config.MountLabel, false); err != nil {
+	if err := label.Relabel(destPath, c.config.MountLabel, true); err != nil {
 		return "", err
 	}