Merge pull request #6449 from timthelion/host-net-docs

Document the potential insecurity of --net host

docs/sources/articles/networking.md

@@ -536,6 +536,11 @@ values.
     **not** let the container reconfigure the host network stack — that
     would require `--privileged=true` — but it does let container
     processes open low-numbered ports like any other root process.
+    It also allows the container to access local network services
+    like D-bus.  This can lead to processes in the container being
+    able to do unexpected things like
+    [restart your computer](https://github.com/dotcloud/docker/issues/6401).
+    You should use this option with caution.
 
  *  `--net=container:NAME_or_ID` — Tells Docker to put this container's
     processes inside of the network stack that has already been created

docs/sources/reference/run.md

@@ -152,7 +152,7 @@ Supported networking modes are:
 
 * none - no networking in the container
 * bridge - (default) connect the container to the bridge via veth interfaces
-* host - use the host's network stack inside the container
+* host - use the host's network stack inside the container.  Note: This gives the container full access to local system services such as D-bus and is therefore considered insecure.
 * container - use another container's network stack
 
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