diff --git a/docs/userguide/dockervolumes.md b/docs/userguide/dockervolumes.md index ef15fa0cbb..c08cf5c5c7 100644 --- a/docs/userguide/dockervolumes.md +++ b/docs/userguide/dockervolumes.md @@ -141,11 +141,18 @@ $ docker run -d -P --name web -v /src/webapp:/opt/webapp:ro training/webapp pyth Here we've mounted the same `/src/webapp` directory but we've added the `ro` option to specify that the mount should be read-only. +Because of [limitations in the `mount` +function](http://lists.linuxfoundation.org/pipermail/containers/2015-April/ +035788.html), moving subdirectories within the host's source directory can give +access from the container to the host's file system. This requires a malicious +user with access to host and its mounted directory. + >**Note**: The host directory is, by its nature, host-dependent. For this >reason, you can't mount a host directory from `Dockerfile` because built images >should be portable. A host directory wouldn't be available on all potential >hosts. + ### Mount a host file as a data volume The `-v` flag can also be used to mount a single file - instead of *just*