1 files changed, 12 insertions, 2 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index a31b823b3c2d..c535f33bbb9c 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1166,6 +1166,14 @@ static struct task_struct *copy_process(unsigned long clone_flags,
                                 current->signal->flags & SIGNAL_UNKILLABLE)
                 return ERR_PTR(-EINVAL);
 
+        /*
+         * If the new process will be in a different pid namespace
+         * don't allow the creation of threads.
+         */
+        if ((clone_flags & (CLONE_VM|CLONE_NEWPID)) &&
+            (task_active_pid_ns(current) != current->nsproxy->pid_ns))
+                return ERR_PTR(-EINVAL);
+
         retval = security_task_create(clone_flags);
         if (retval)
                 goto fork_out;
@@ -1660,8 +1668,10 @@ SYSCALL_DEFINE5(clone, unsigned long, clone_flags, unsigned long, newsp,
                  int, tls_val)
 #endif
 {
-        return do_fork(clone_flags, newsp, 0,
-                parent_tidptr, child_tidptr);
+        long ret = do_fork(clone_flags, newsp, 0, parent_tidptr, child_tidptr);
+        asmlinkage_protect(5, ret, clone_flags, newsp,
+                        parent_tidptr, child_tidptr, tls_val);
+        return ret;
 }
 #endif