• Eric W. Biederman's avatar
    vfs: Don't copy mount bind mounts of /proc/<pid>/ns/mnt between namespaces · 4ce5d2b1
    Eric W. Biederman authored
    Don't copy bind mounts of /proc/<pid>/ns/mnt between namespaces.
    These files hold references to a mount namespace and copying them
    between namespaces could result in a reference counting loop.
    
    The current mnt_ns_loop test prevents loops on the assumption that
    mounts don't cross between namespaces.  Unfortunately unsharing a
    mount namespace and shared substrees can both cause mounts to
    propogate between mount namespaces.
    
    Add two flags CL_COPY_UNBINDABLE and CL_COPY_MNT_NS_FILE are added to
    control this behavior, and CL_COPY_ALL is redefined as both of them.
    Signed-off-by: 's avatar"Eric W. Biederman" <ebiederm@xmission.com>
    4ce5d2b1
pnode.h 1.55 KB