1 files changed, 18 insertions, 28 deletions

diff --git a/fs/namespace.c b/fs/namespace.c
index d82910f33dc4..2bad25709b2c 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -132,16 +132,6 @@ EXPORT_SYMBOL_GPL(fs_kobj);
  */
 __cacheline_aligned_in_smp DEFINE_SEQLOCK(mount_lock);
 
-static inline struct mnt_namespace *node_to_mnt_ns(const struct rb_node *node)
-{
-	struct ns_common *ns;
-
-	if (!node)
-		return NULL;
-	ns = rb_entry(node, struct ns_common, ns_tree_node);
-	return container_of(ns, struct mnt_namespace, ns);
-}
-
 static void mnt_ns_release(struct mnt_namespace *ns)
 {
 	/* keep alive for {list,stat}mount() */
@@ -151,7 +141,8 @@ static void mnt_ns_release(struct mnt_namespace *ns)
 		kfree(ns);
 	}
 }
-DEFINE_FREE(mnt_ns_release, struct mnt_namespace *, if (_T) mnt_ns_release(_T))
+DEFINE_FREE(mnt_ns_release, struct mnt_namespace *,
+	    if (!IS_ERR(_T)) mnt_ns_release(_T))
 
 static void mnt_ns_release_rcu(struct rcu_head *rcu)
 {
@@ -5454,11 +5445,11 @@ static int statmount_string(struct kstatmount *s, u64 flag)
 		ret = statmount_sb_source(s, seq);
 		break;
 	case STATMOUNT_MNT_UIDMAP:
-		sm->mnt_uidmap = start;
+		offp = &sm->mnt_uidmap;
 		ret = statmount_mnt_uidmap(s, seq);
 		break;
 	case STATMOUNT_MNT_GIDMAP:
-		sm->mnt_gidmap = start;
+		offp = &sm->mnt_gidmap;
 		ret = statmount_mnt_gidmap(s, seq);
 		break;
 	default:
@@ -5736,7 +5727,7 @@ static int copy_mnt_id_req(const struct mnt_id_req __user *req,
 	ret = copy_struct_from_user(kreq, sizeof(*kreq), req, usize);
 	if (ret)
 		return ret;
-	if (kreq->spare != 0)
+	if (kreq->mnt_ns_fd != 0 && kreq->mnt_ns_id)
 		return -EINVAL;
 	/* The first valid unique mount id is MNT_UNIQUE_ID_OFFSET + 1. */
 	if (kreq->mnt_id <= MNT_UNIQUE_ID_OFFSET)
@@ -5753,16 +5744,12 @@ static struct mnt_namespace *grab_requested_mnt_ns(const struct mnt_id_req *kreq
 {
 	struct mnt_namespace *mnt_ns;
 
-	if (kreq->mnt_ns_id && kreq->spare)
-		return ERR_PTR(-EINVAL);
-
-	if (kreq->mnt_ns_id)
-		return lookup_mnt_ns(kreq->mnt_ns_id);
-
-	if (kreq->spare) {
+	if (kreq->mnt_ns_id) {
+		mnt_ns = lookup_mnt_ns(kreq->mnt_ns_id);
+	} else if (kreq->mnt_ns_fd) {
 		struct ns_common *ns;
 
-		CLASS(fd, f)(kreq->spare);
+		CLASS(fd, f)(kreq->mnt_ns_fd);
 		if (fd_empty(f))
 			return ERR_PTR(-EBADF);
 
@@ -5777,6 +5764,8 @@ static struct mnt_namespace *grab_requested_mnt_ns(const struct mnt_id_req *kreq
 	} else {
 		mnt_ns = current->nsproxy->mnt_ns;
 	}
+	if (!mnt_ns)
+		return ERR_PTR(-ENOENT);
 
 	refcount_inc(&mnt_ns->passive);
 	return mnt_ns;
@@ -5801,8 +5790,8 @@ SYSCALL_DEFINE4(statmount, const struct mnt_id_req __user *, req,
 		return ret;
 
 	ns = grab_requested_mnt_ns(&kreq);
-	if (!ns)
-		return -ENOENT;
+	if (IS_ERR(ns))
+		return PTR_ERR(ns);
 
 	if (kreq.mnt_ns_id && (ns != current->nsproxy->mnt_ns) &&
 	    !ns_capable_noaudit(ns->user_ns, CAP_SYS_ADMIN))
@@ -5912,8 +5901,8 @@ static void __free_klistmount_free(const struct klistmount *kls)
 static inline int prepare_klistmount(struct klistmount *kls, struct mnt_id_req *kreq,
 				     size_t nr_mnt_ids)
 {
-
 	u64 last_mnt_id = kreq->param;
+	struct mnt_namespace *ns;
 
 	/* The first valid unique mount id is MNT_UNIQUE_ID_OFFSET + 1. */
 	if (last_mnt_id != 0 && last_mnt_id <= MNT_UNIQUE_ID_OFFSET)
@@ -5927,9 +5916,10 @@ static inline int prepare_klistmount(struct klistmount *kls, struct mnt_id_req *
 	if (!kls->kmnt_ids)
 		return -ENOMEM;
 
-	kls->ns = grab_requested_mnt_ns(kreq);
-	if (!kls->ns)
-		return -ENOENT;
+	ns = grab_requested_mnt_ns(kreq);
+	if (IS_ERR(ns))
+		return PTR_ERR(ns);
+	kls->ns = ns;
 
 	kls->mnt_parent_id = kreq->mnt_id;
 	return 0;