#include "util.h"
+/*
+ * The work queue is used to avoid the cost of synchronize_rcu in kern_unmount.
+ */
+static void free_ipc(struct work_struct *unused);
+static DECLARE_WORK(free_ipc_work, free_ipc);
+
static struct ucounts *inc_ipc_namespaces(struct user_namespace *ns)
{
return inc_ucount(ns, current_euid(), UCOUNT_IPC_NAMESPACES);
int err;
err = -ENOSPC;
+ again:
ucounts = inc_ipc_namespaces(user_ns);
- if (!ucounts)
+ if (!ucounts) {
+ /*
+ * IPC namespaces are freed asynchronously, by free_ipc_work.
+ * If frees were pending, flush_work will wait, and
+ * return true. Fail the allocation if no frees are pending.
+ */
+ if (flush_work(&free_ipc_work))
+ goto again;
goto fail;
+ }
err = -ENOMEM;
ns = kzalloc(sizeof(struct ipc_namespace), GFP_KERNEL_ACCOUNT);
}
/*
- * The work queue is used to avoid the cost of synchronize_rcu in kern_unmount.
- */
-static DECLARE_WORK(free_ipc_work, free_ipc);
-
-/*
* put_ipc_ns - drop a reference to an ipc namespace.
* @ns: the namespace to put
*