Merge branch 'omap/multiplatform-fixes', tag 'v3.8-rc5' into next/multiplatform

[firefly-linux-kernel-4.4.55.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 85f6d536608d282c97988701951d82afb20d5ba7..c535f33bbb9c9ad108c394618474bbbce1f64f86 100644 (file)
--- 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;
@@ -1613,7 +1621,6 @@ long do_fork(unsigned long clone_flags,
        return nr;
 }
 
-#ifdef CONFIG_GENERIC_KERNEL_THREAD
 /*
  * Create a kernel thread.
  */
@@ -1622,7 +1629,6 @@ pid_t kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
        return do_fork(flags|CLONE_VM|CLONE_UNTRACED, (unsigned long)fn,
                (unsigned long)arg, NULL, NULL);
 }
-#endif
 
 #ifdef __ARCH_WANT_SYS_FORK
 SYSCALL_DEFINE0(fork)
@@ -1662,8 +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