1 files changed, 24 insertions, 0 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index 50ca17d3cb45..a3035223d421 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -2732,6 +2732,30 @@ bool our_mnt(struct vfsmount *mnt)
         return check_mnt(real_mount(mnt));
 }
 
+bool current_chrooted(void)
+{
+        /* Does the current process have a non-standard root */
+        struct path ns_root;
+        struct path fs_root;
+        bool chrooted;
+
+        /* Find the namespace root */
+        ns_root.mnt = &current->nsproxy->mnt_ns->root->mnt;
+        ns_root.dentry = ns_root.mnt->mnt_root;
+        path_get(&ns_root);
+        while (d_mountpoint(ns_root.dentry) && follow_down_one(&ns_root))
+                ;
+
+        get_fs_root(current->fs, &fs_root);
+
+        chrooted = !path_equal(&fs_root, &ns_root);
+
+        path_put(&fs_root);
+        path_put(&ns_root);
+
+        return chrooted;
+}
+
 static void *mntns_get(struct task_struct *task)
 {
         struct mnt_namespace *ns = NULL;