From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754023Ab0DZRAF (ORCPT ); Mon, 26 Apr 2010 13:00:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35203 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753972Ab0DZRAD (ORCPT ); Mon, 26 Apr 2010 13:00:03 -0400 Date: Mon, 26 Apr 2010 12:33:03 -0400 From: Rik van Riel To: Dan Carpenter Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org Subject: [PATCH] mmap: check ->vm_ops before dereferencing Message-ID: <20100426123303.5ef4ac01@annuminas.surriel.com> In-Reply-To: <20100426100305.GP29093@bicker> References: <20100426100305.GP29093@bicker> Organization: Red Hat, Inc. Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Check whether the VMA has a vm_ops before calling close, just like we check vm_ops before calling open a few dozen lines higher up in the function. Signed-off-by: Rik van Riel Reported-by: Dan Carpenter diff --git a/mm/mmap.c b/mm/mmap.c index f90ea92..456ec6f 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1977,7 +1977,8 @@ static int __split_vma(struct mm_struct * mm, struct vm_area_struct * vma, return 0; /* Clean everything up if vma_adjust failed. */ - new->vm_ops->close(new); + if (new->vm_ops && new->vm_ops->close) + new->vm_ops->close(new); if (new->vm_file) { if (vma->vm_flags & VM_EXECUTABLE) removed_exe_file_vma(mm);