3 files changed, 23 insertions, 36 deletions

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index d3a588d0dcf6..56e811f9e5fa 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -896,22 +896,23 @@ static struct file *mqueue_file_open(struct filename *name,
 				     struct vfsmount *mnt, int oflag, bool ro,
 				     umode_t mode, struct mq_attr *attr)
 {
-	struct path path __free(path_put) = {};
 	struct dentry *dentry;
+	struct file *file;
 	int ret;
 
-	dentry = lookup_noperm(&QSTR(name->name), mnt->mnt_root);
+	dentry = start_creating_noperm(mnt->mnt_root, &QSTR(name->name));
 	if (IS_ERR(dentry))
 		return ERR_CAST(dentry);
 
-	path.dentry = dentry;
-	path.mnt = mntget(mnt);
-
-	ret = prepare_open(path.dentry, oflag, ro, mode, name, attr);
-	if (ret)
-		return ERR_PTR(ret);
+	ret = prepare_open(dentry, oflag, ro, mode, name, attr);
+	file = ERR_PTR(ret);
+	if (!ret) {
+		const struct path path = { .mnt = mnt, .dentry = dentry };
+		file = dentry_open(&path, oflag, current_cred());
+	}
 
-	return dentry_open(&path, oflag, current_cred());
+	end_creating(dentry);
+	return file;
 }
 
 static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
@@ -919,9 +920,7 @@ static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
 {
 	struct filename *name __free(putname) = NULL;;
 	struct vfsmount *mnt = current->nsproxy->ipc_ns->mq_mnt;
-	struct dentry *root = mnt->mnt_root;
-	int fd;
-	int ro;
+	int fd, ro;
 
 	audit_mq_open(oflag, mode, attr);
 
@@ -930,9 +929,7 @@ static int do_mq_open(const char __user *u_name, int oflag, umode_t mode,
 		return PTR_ERR(name);
 
 	ro = mnt_want_write(mnt);	/* we'll drop it in any case */
-	inode_lock(d_inode(root));
 	fd = FD_ADD(O_CLOEXEC, mqueue_file_open(name, mnt, oflag, ro, mode, attr));
-	inode_unlock(d_inode(root));
 	if (!ro)
 		mnt_drop_write(mnt);
 	return fd;
@@ -953,7 +950,7 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 	int err;
 	struct filename *name;
 	struct dentry *dentry;
-	struct inode *inode = NULL;
+	struct inode *inode;
 	struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
 	struct vfsmount *mnt = ipc_ns->mq_mnt;
 
@@ -965,26 +962,20 @@ SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
 	err = mnt_want_write(mnt);
 	if (err)
 		goto out_name;
-	inode_lock_nested(d_inode(mnt->mnt_root), I_MUTEX_PARENT);
-	dentry = lookup_noperm(&QSTR(name->name), mnt->mnt_root);
+	dentry = start_removing_noperm(mnt->mnt_root, &QSTR(name->name));
 	if (IS_ERR(dentry)) {
 		err = PTR_ERR(dentry);
-		goto out_unlock;
+		goto out_drop_write;
 	}
 
 	inode = d_inode(dentry);
-	if (!inode) {
-		err = -ENOENT;
-	} else {
-		ihold(inode);
-		err = vfs_unlink(&nop_mnt_idmap, d_inode(dentry->d_parent),
-				 dentry, NULL);
-	}
-	dput(dentry);
-
-out_unlock:
-	inode_unlock(d_inode(mnt->mnt_root));
+	ihold(inode);
+	err = vfs_unlink(&nop_mnt_idmap, d_inode(mnt->mnt_root),
+			 dentry, NULL);
+	end_removing(dentry);
 	iput(inode);
+
+out_drop_write:
 	mnt_drop_write(mnt);
 out_name:
 	putname(name);
diff --git a/ipc/msgutil.c b/ipc/msgutil.c
index 7a03f6d03de3..e28f0cecb2ec 100644
--- a/ipc/msgutil.c
+++ b/ipc/msgutil.c
@@ -27,13 +27,8 @@ DEFINE_SPINLOCK(mq_lock);
  * and not CONFIG_IPC_NS.
  */
 struct ipc_namespace init_ipc_ns = {
-	.ns.__ns_ref = REFCOUNT_INIT(1),
+	.ns = NS_COMMON_INIT(init_ipc_ns),
 	.user_ns = &init_user_ns,
-	.ns.inum = ns_init_inum(&init_ipc_ns),
-#ifdef CONFIG_IPC_NS
-	.ns.ops = &ipcns_operations,
-#endif
-	.ns.ns_type = ns_common_type(&init_ipc_ns),
 };
 
 struct msg_msgseg {
diff --git a/ipc/namespace.c b/ipc/namespace.c
index 59b12fcb40bd..c0dbfdd9015f 100644
--- a/ipc/namespace.c
+++ b/ipc/namespace.c
@@ -66,6 +66,7 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns,
 	if (err)
 		goto fail_free;
 
+	ns_tree_gen_id(ns);
 	ns->user_ns = get_user_ns(user_ns);
 	ns->ucounts = ucounts;
 
@@ -86,7 +87,7 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns,
 
 	sem_init_ns(ns);
 	shm_init_ns(ns);
-	ns_tree_add(ns);
+	ns_tree_add_raw(ns);
 
 	return ns;