natsemi: Avoid IntrStatus lossage if RX state machine resets.

[powerpc.git] / kernel / utsname.c

diff --git a/kernel/utsname.c b/kernel/utsname.c
index 1824384..c859164 100644 (file)
--- a/kernel/utsname.c
+++ b/kernel/utsname.c
@@ -14,6 +14,41 @@
 #include <linux/utsname.h>
 #include <linux/version.h>
 
+/*
+ * Clone a new ns copying an original utsname, setting refcount to 1
+ * @old_ns: namespace to clone
+ * Return NULL on error (failure to kmalloc), new ns otherwise
+ */
+static struct uts_namespace *clone_uts_ns(struct uts_namespace *old_ns)
+{
+       struct uts_namespace *ns;
+
+       ns = kmalloc(sizeof(struct uts_namespace), GFP_KERNEL);
+       if (ns) {
+               memcpy(&ns->name, &old_ns->name, sizeof(ns->name));
+               kref_init(&ns->kref);
+       }
+       return ns;
+}
+
+/*
+ * unshare the current process' utsname namespace.
+ * called only in sys_unshare()
+ */
+int unshare_utsname(unsigned long unshare_flags, struct uts_namespace **new_uts)
+{
+       if (unshare_flags & CLONE_NEWUTS) {
+               if (!capable(CAP_SYS_ADMIN))
+                       return -EPERM;
+
+               *new_uts = clone_uts_ns(current->nsproxy->uts_ns);
+               if (!*new_uts)
+                       return -ENOMEM;
+       }
+
+       return 0;
+}
+
 /*
  * Copy task tsk's utsname namespace, or clone it if flags
  * specifies CLONE_NEWUTS.  In latter case, changes to the
@@ -23,6 +58,7 @@
 int copy_utsname(int flags, struct task_struct *tsk)
 {
        struct uts_namespace *old_ns = tsk->nsproxy->uts_ns;
+       struct uts_namespace *new_ns;
        int err = 0;
 
        if (!old_ns)
@@ -30,6 +66,23 @@ int copy_utsname(int flags, struct task_struct *tsk)
 
        get_uts_ns(old_ns);
 
+       if (!(flags & CLONE_NEWUTS))
+               return 0;
+
+       if (!capable(CAP_SYS_ADMIN)) {
+               err = -EPERM;
+               goto out;
+       }
+
+       new_ns = clone_uts_ns(old_ns);
+       if (!new_ns) {
+               err = -ENOMEM;
+               goto out;
+       }
+       tsk->nsproxy->uts_ns = new_ns;
+
+out:
+       put_uts_ns(old_ns);
        return err;
 }