2 files changed, 21 insertions, 12 deletions

diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
index 478bad2745e3..eb00be205811 100644
--- a/kernel/pid_namespace.c
+++ b/kernel/pid_namespace.c
@@ -133,19 +133,26 @@ struct pid_namespace *copy_pid_ns(unsigned long flags, struct pid_namespace *old
         return create_pid_namespace(old_ns);
 }
 
-void free_pid_ns(struct kref *kref)
+static void free_pid_ns(struct kref *kref)
 {
-        struct pid_namespace *ns, *parent;
+        struct pid_namespace *ns;
 
         ns = container_of(kref, struct pid_namespace, kref);
-
-        parent = ns->parent;
         destroy_pid_namespace(ns);
+}
 
-        if (parent != NULL)
-                put_pid_ns(parent);
+void put_pid_ns(struct pid_namespace *ns)
+{
+        struct pid_namespace *parent;
+
+        while (ns != &init_pid_ns) {
+                parent = ns->parent;
+                if (!kref_put(&ns->kref, free_pid_ns))
+                        break;
+                ns = parent;
+        }
 }
-EXPORT_SYMBOL_GPL(free_pid_ns);
+EXPORT_SYMBOL_GPL(put_pid_ns);
 
 void zap_pid_ns_processes(struct pid_namespace *pid_ns)
 {
diff --git a/kernel/sys.c b/kernel/sys.c
index c5cb5b99cb81..01865c6fb6a0 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1265,15 +1265,16 @@ DECLARE_RWSEM(uts_sem);
  * Work around broken programs that cannot handle "Linux 3.0".
  * Instead we map 3.x to 2.6.40+x, so e.g. 3.0 would be 2.6.40
  */
-static int override_release(char __user *release, int len)
+static int override_release(char __user *release, size_t len)
 {
         int ret = 0;
-        char buf[65];
 
         if (current->personality & UNAME26) {
-                char *rest = UTS_RELEASE;
+                const char *rest = UTS_RELEASE;
+                char buf[65] = { 0 };
                 int ndots = 0;
                 unsigned v;
+                size_t copy;
 
                 while (*rest) {
                         if (*rest == '.' && ++ndots >= 3)
@@ -1283,8 +1284,9 @@ static int override_release(char __user *release, int len)
                         rest++;
                 }
                 v = ((LINUX_VERSION_CODE >> 8) & 0xff) + 40;
-                snprintf(buf, len, "2.6.%u%s", v, rest);
-                ret = copy_to_user(release, buf, len);
+                copy = min(sizeof(buf), max_t(size_t, 1, len));
+                copy = scnprintf(buf, copy, "2.6.%u%s", v, rest);
+                ret = copy_to_user(release, buf, copy + 1);
         }
         return ret;
 }