1 files changed, 53 insertions, 2 deletions

diff --git a/ipc/util.c b/ipc/util.c
index 5432b8e34c9b..910db7748199 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -248,7 +248,7 @@ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
  *      This routine is called by sys_msgget, sys_semget() and sys_shmget()
  *      when the key is IPC_PRIVATE.
  */
-int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
+static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids,
                 struct ipc_ops *ops, struct ipc_params *params)
 {
         int err;
@@ -312,7 +312,7 @@ static int ipc_check_perms(struct kern_ipc_perm *ipcp, struct ipc_ops *ops,
  *
  *      On success, the ipc id is returned.
  */
-int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
+static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids,
                 struct ipc_ops *ops, struct ipc_params *params)
 {
         struct kern_ipc_perm *ipcp;
@@ -710,6 +710,57 @@ struct kern_ipc_perm *ipc_lock_down(struct ipc_ids *ids, int id)
         return out;
 }
 
+struct kern_ipc_perm *ipc_lock_check_down(struct ipc_ids *ids, int id)
+{
+        struct kern_ipc_perm *out;
+
+        out = ipc_lock_down(ids, id);
+        if (IS_ERR(out))
+                return out;
+
+        if (ipc_checkid(out, id)) {
+                ipc_unlock(out);
+                return ERR_PTR(-EIDRM);
+        }
+
+        return out;
+}
+
+struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id)
+{
+        struct kern_ipc_perm *out;
+
+        out = ipc_lock(ids, id);
+        if (IS_ERR(out))
+                return out;
+
+        if (ipc_checkid(out, id)) {
+                ipc_unlock(out);
+                return ERR_PTR(-EIDRM);
+        }
+
+        return out;
+}
+
+/**
+ * ipcget - Common sys_*get() code
+ * @ns : namsepace
+ * @ids : IPC identifier set
+ * @ops : operations to be called on ipc object creation, permission checks
+ *        and further checks
+ * @params : the parameters needed by the previous operations.
+ *
+ * Common routine called by sys_msgget(), sys_semget() and sys_shmget().
+ */
+int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids,
+                        struct ipc_ops *ops, struct ipc_params *params)
+{
+        if (params->key == IPC_PRIVATE)
+                return ipcget_new(ns, ids, ops, params);
+        else
+                return ipcget_public(ns, ids, ops, params);
+}
+
 #ifdef __ARCH_WANT_IPC_PARSE_VERSION