NFSv4: Fix a BAD_SEQUENCEID condition.

[safe/jmp/linux-2.6] / kernel / nsproxy.c

diff --git a/kernel/nsproxy.c b/kernel/nsproxy.c
index f5d332c..1d3ef29 100644 (file)
--- a/kernel/nsproxy.c
+++ b/kernel/nsproxy.c
@@ -14,7 +14,6 @@
  */
 
 #include <linux/module.h>
-#include <linux/version.h>
 #include <linux/nsproxy.h>
 #include <linux/init_task.h>
 #include <linux/mnt_namespace.h>
@@ -139,15 +138,21 @@ int copy_namespaces(unsigned long flags, struct task_struct *tsk)
                goto out;
        }
 
-       new_ns = create_new_namespaces(flags, tsk, tsk->fs);
-       if (IS_ERR(new_ns)) {
-               err = PTR_ERR(new_ns);
+       /*
+        * CLONE_NEWIPC must detach from the undolist: after switching
+        * to a new ipc namespace, the semaphore arrays from the old
+        * namespace are unreachable.  In clone parlance, CLONE_SYSVSEM
+        * means share undolist with parent, so we must forbid using
+        * it along with CLONE_NEWIPC.
+        */
+       if ((flags & CLONE_NEWIPC) && (flags & CLONE_SYSVSEM)) {
+               err = -EINVAL;
                goto out;
        }
 
-       err = ns_cgroup_clone(tsk);
-       if (err) {
-               put_nsproxy(new_ns);
+       new_ns = create_new_namespaces(flags, tsk, tsk->fs);
+       if (IS_ERR(new_ns)) {
+               err = PTR_ERR(new_ns);
                goto out;
        }
 
@@ -197,7 +202,7 @@ int unshare_nsproxy_namespaces(unsigned long unshare_flags,
                goto out;
        }
 
-       err = ns_cgroup_clone(current);
+       err = ns_cgroup_clone(current, task_pid(current));
        if (err)
                put_nsproxy(*new_nsp);