Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...

[linux-2.6-block.git] / fs / namespace.c

diff --git a/fs/namespace.c b/fs/namespace.c
index fe1c77145a78491b0dc124cdb7f4ca22d8eba275..820af6a1dd6b15f9f1b479b17a2c03634c40f16c 100644 (file)
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1573,17 +1573,13 @@ SYSCALL_DEFINE1(oldumount, char __user *, name)
 static bool is_mnt_ns_file(struct dentry *dentry)
 {
        /* Is this a proxy for a mount namespace? */
-       struct inode *inode = dentry->d_inode;
-       struct proc_ns *ei;
-
-       if (!proc_ns_inode(inode))
-               return false;
-
-       ei = get_proc_ns(inode);
-       if (ei->ns_ops != &mntns_operations)
-               return false;
+       return dentry->d_op == &ns_dentry_operations &&
+              dentry->d_fsdata == &mntns_operations;
+}
 
-       return true;
+struct mnt_namespace *to_mnt_ns(struct ns_common *ns)
+{
+       return container_of(ns, struct mnt_namespace, ns);
 }
 
 static bool mnt_ns_loop(struct dentry *dentry)
@@ -1595,7 +1591,7 @@ static bool mnt_ns_loop(struct dentry *dentry)
        if (!is_mnt_ns_file(dentry))
                return false;
 
-       mnt_ns = get_proc_ns(dentry->d_inode)->ns;
+       mnt_ns = to_mnt_ns(get_proc_ns(dentry->d_inode));
        return current->nsproxy->mnt_ns->seq >= mnt_ns->seq;
 }
 
@@ -2023,7 +2019,10 @@ static int do_loopback(struct path *path, const char *old_name,
        if (IS_MNT_UNBINDABLE(old))
                goto out2;
 
-       if (!check_mnt(parent) || !check_mnt(old))
+       if (!check_mnt(parent))
+               goto out2;
+
+       if (!check_mnt(old) && old_path.dentry->d_op != &ns_dentry_operations)
                goto out2;
 
        if (!recurse && has_locked_children(old, old_path.dentry))
@@ -2649,7 +2648,7 @@ dput_out:
 
 static void free_mnt_ns(struct mnt_namespace *ns)
 {
-       proc_free_inum(ns->proc_inum);
+       ns_free_inum(&ns->ns);
        put_user_ns(ns->user_ns);
        kfree(ns);
 }
@@ -2671,11 +2670,12 @@ static struct mnt_namespace *alloc_mnt_ns(struct user_namespace *user_ns)
        new_ns = kmalloc(sizeof(struct mnt_namespace), GFP_KERNEL);
        if (!new_ns)
                return ERR_PTR(-ENOMEM);
-       ret = proc_alloc_inum(&new_ns->proc_inum);
+       ret = ns_alloc_inum(&new_ns->ns);
        if (ret) {
                kfree(new_ns);
                return ERR_PTR(ret);
        }
+       new_ns->ns.ops = &mntns_operations;
        new_ns->seq = atomic64_add_return(1, &mnt_ns_seq);
        atomic_set(&new_ns->count, 1);
        new_ns->root = NULL;
@@ -3156,31 +3156,31 @@ found:
        return visible;
 }
 
-static void *mntns_get(struct task_struct *task)
+static struct ns_common *mntns_get(struct task_struct *task)
 {
-       struct mnt_namespace *ns = NULL;
+       struct ns_common *ns = NULL;
        struct nsproxy *nsproxy;
 
        task_lock(task);
        nsproxy = task->nsproxy;
        if (nsproxy) {
-               ns = nsproxy->mnt_ns;
-               get_mnt_ns(ns);
+               ns = &nsproxy->mnt_ns->ns;
+               get_mnt_ns(to_mnt_ns(ns));
        }
        task_unlock(task);
 
        return ns;
 }
 
-static void mntns_put(void *ns)
+static void mntns_put(struct ns_common *ns)
 {
-       put_mnt_ns(ns);
+       put_mnt_ns(to_mnt_ns(ns));
 }
 
-static int mntns_install(struct nsproxy *nsproxy, void *ns)
+static int mntns_install(struct nsproxy *nsproxy, struct ns_common *ns)
 {
        struct fs_struct *fs = current->fs;
-       struct mnt_namespace *mnt_ns = ns;
+       struct mnt_namespace *mnt_ns = to_mnt_ns(ns);
        struct path root;
 
        if (!ns_capable(mnt_ns->user_ns, CAP_SYS_ADMIN) ||
@@ -3210,17 +3210,10 @@ static int mntns_install(struct nsproxy *nsproxy, void *ns)
        return 0;
 }
 
-static unsigned int mntns_inum(void *ns)
-{
-       struct mnt_namespace *mnt_ns = ns;
-       return mnt_ns->proc_inum;
-}
-
 const struct proc_ns_operations mntns_operations = {
        .name           = "mnt",
        .type           = CLONE_NEWNS,
        .get            = mntns_get,
        .put            = mntns_put,
        .install        = mntns_install,
-       .inum           = mntns_inum,
 };