[PATCH] small fix for not releasing the mmap semaphore in i386/arch_setup_additional_pages

the VDSO randomization code on i386 fails to release the mmap semaphore
if insert_vm_struct() fails.

[ Made the conditional unlikely. -- Linus ]
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

arch/i386/kernel/sysenter.c

@@ -148,8 +148,10 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 	vma->vm_mm = mm;
 
 	ret = insert_vm_struct(mm, vma);
-	if (ret)
-		goto free_vma;
+	if (unlikely(ret)) {
+		kmem_cache_free(vm_area_cachep, vma);
+		goto up_fail;
+	}
 
 	current->mm->context.vdso = (void *)addr;
 	current_thread_info()->sysenter_return =
@@ -158,10 +160,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int exstack)
 up_fail:
 	up_write(&mm->mmap_sem);
 	return ret;
-
-free_vma:
-	kmem_cache_free(vm_area_cachep, vma);
-	return ret;
 }
 
 const char *arch_vma_name(struct vm_area_struct *vma)