diff mbox series

[048/104] virtiofsd: move to an empty network namespace

Message ID 20191212163904.159893-49-dgilbert@redhat.com
State New
Headers show
Series virtiofs daemon [all] | expand

Commit Message

Dr. David Alan Gilbert Dec. 12, 2019, 4:38 p.m. UTC 
From: Stefan Hajnoczi <stefanha@redhat.com>

If the process is compromised there should be no network access.  Use an
empty network namespace to sandbox networking.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 tools/virtiofsd/passthrough_ll.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

Comments

Daniel P. Berrangé Jan. 6, 2020, 2:37 p.m. UTC | #1 
On Thu, Dec 12, 2019 at 04:38:08PM +0000, Dr. David Alan Gilbert (git) wrote:
> From: Stefan Hajnoczi <stefanha@redhat.com>
> 
> If the process is compromised there should be no network access.  Use an
> empty network namespace to sandbox networking.
> 
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
> ---
>  tools/virtiofsd/passthrough_ll.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

Regards,
Daniel
diff mbox series

Patch

diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index 606824f002..135a99f2fd 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -1926,6 +1926,19 @@  static void print_capabilities(void)
     printf("}\n");
 }
 
+/*
+ * Called after our UNIX domain sockets have been created, now we can move to
+ * an empty network namespace to prevent TCP/IP and other network activity in
+ * case this process is compromised.
+ */
+static void setup_net_namespace(void)
+{
+    if (unshare(CLONE_NEWNET) != 0) {
+        fuse_log(FUSE_LOG_ERR, "unshare(CLONE_NEWNET): %m\n");
+        exit(1);
+    }
+}
+
 /* This magic is based on lxc's lxc_pivot_root() */
 static void setup_pivot_root(const char *source)
 {
@@ -2017,6 +2030,7 @@  static void setup_mount_namespace(const char *source)
  */
 static void setup_sandbox(struct lo_data *lo)
 {
+    setup_net_namespace();
     setup_mount_namespace(lo->source);
 }