Frank Filz has uploaded this change for review. ( https://review.gerrithub.io/c/ffilz/nfs-ganesha/+/502536 ) Change subject: Introduce fsal_lookup_path helper ...................................................................... Introduce fsal_lookup_path helper Instead of using FSAL API lookup_path method to accomplish subdir mounts (and 9P attach), do a path walk in fsal_helper.c using the normal lookup method. This brings that path walk into common code applicable to all FSALs and works if mount_path_pseudo is true (in which case the mount path may not be able to be looked up in the backend). The helper function checks that each component is not ".." and is a directory. This prevents security hacking by using ".." to escape the export or using a symlink to escape the export. It also neatly assures we never allow mounting a single file. We also allow extra '/' in the path beyond the export root and allow "." components. Change-Id: I301a7cf34185fd7f57c73c21a069366d92abd25f Signed-off-by: Frank S. Filz <ffilzlnx(a)mindspring.com&gt; --- M src/FSAL/fsal_helper.c M src/Protocols/9P/9p_attach.c M src/Protocols/NFS/mnt_Mnt.c M src/include/fsal.h 4 files changed, 181 insertions(+), 42 deletions(-) git pull ssh://review.gerrithub.io:29418/ffilz/nfs-ganesha refs/changes/36/502536/1 -- To view, visit https://review.gerrithub.io/c/ffilz/nfs-ganesha/+/502536 To unsubscribe, or for help writing mail filters, visit https://review.gerrithub.io/settings Gerrit-Project: ffilz/nfs-ganesha Gerrit-Branch: next Gerrit-Change-Id: I301a7cf34185fd7f57c73c21a069366d92abd25f Gerrit-Change-Number: 502536 Gerrit-PatchSet: 1 Gerrit-Owner: Frank Filz <ffilzlnx(a)mindspring.com&gt; Gerrit-MessageType: newchange