1 files changed, 18 insertions, 6 deletions

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 7c08eb3c258d..12ad7860bb88 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -45,6 +45,7 @@
 
 struct mqueue_fs_context {
 	struct ipc_namespace	*ipc_ns;
+	bool			 newns;	/* Set if newly created ipc namespace */
 };
 
 #define MQUEUE_MAGIC	0x19800202
@@ -163,8 +164,6 @@ static void remove_notification(struct mqueue_inode_info *info);
 
 static struct kmem_cache *mqueue_inode_cachep;
 
-static struct ctl_table_header *mq_sysctl_table;
-
 static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
 {
 	return container_of(inode, struct mqueue_inode_info, vfs_inode);
@@ -427,6 +426,14 @@ static int mqueue_get_tree(struct fs_context *fc)
 {
 	struct mqueue_fs_context *ctx = fc->fs_private;
 
+	/*
+	 * With a newly created ipc namespace, we don't need to do a search
+	 * for an ipc namespace match, but we still need to set s_fs_info.
+	 */
+	if (ctx->newns) {
+		fc->s_fs_info = ctx->ipc_ns;
+		return get_tree_nodev(fc, mqueue_fill_super);
+	}
 	return get_tree_keyed(fc, mqueue_fill_super, ctx->ipc_ns);
 }
 
@@ -454,6 +461,10 @@ static int mqueue_init_fs_context(struct fs_context *fc)
 	return 0;
 }
 
+/*
+ * mq_init_ns() is currently the only caller of mq_create_mount().
+ * So the ns parameter is always a newly created ipc namespace.
+ */
 static struct vfsmount *mq_create_mount(struct ipc_namespace *ns)
 {
 	struct mqueue_fs_context *ctx;
@@ -465,6 +476,7 @@ static struct vfsmount *mq_create_mount(struct ipc_namespace *ns)
 		return ERR_CAST(fc);
 
 	ctx = fc->fs_private;
+	ctx->newns = true;
 	put_ipc_ns(ctx->ipc_ns);
 	ctx->ipc_ns = get_ipc_ns(ns);
 	put_user_ns(fc->user_ns);
@@ -1713,8 +1725,10 @@ static int __init init_mqueue_fs(void)
 	if (mqueue_inode_cachep == NULL)
 		return -ENOMEM;
 
-	/* ignore failures - they are not fatal */
-	mq_sysctl_table = mq_register_sysctl_table();
+	if (!setup_mq_sysctls(&init_ipc_ns)) {
+		pr_warn("sysctl registration failed\n");
+		return -ENOMEM;
+	}
 
 	error = register_filesystem(&mqueue_fs_type);
 	if (error)
@@ -1731,8 +1745,6 @@ static int __init init_mqueue_fs(void)
 out_filesystem:
 	unregister_filesystem(&mqueue_fs_type);
 out_sysctl:
-	if (mq_sysctl_table)
-		unregister_sysctl_table(mq_sysctl_table);
 	kmem_cache_destroy(mqueue_inode_cachep);
 	return error;
 }