From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932378Ab2FOPpj (ORCPT ); Fri, 15 Jun 2012 11:45:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48831 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932135Ab2FOPpd (ORCPT ); Fri, 15 Jun 2012 11:45:33 -0400 Date: Fri, 15 Jun 2012 17:43:25 +0200 From: Oleg Nesterov To: Ingo Molnar Cc: Ananth N Mavinakayanahalli , Anton Arapov , Peter Zijlstra , Srikar Dronamraju , linux-kernel@vger.kernel.org Subject: [PATCH 02/15] uprobes: __copy_insn() should ensure a_ops->readpage != NULL Message-ID: <20120615154325.GA9568@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120615154241.GA9524@redhat.com> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __copy_insn() blindly calls read_mapping_page(), this will crash the kernel if ->readpage == NULL, add the necessary check. For example, hugetlbfs_aops->readpage is NULL. Perhaps we should change read_mapping_page() instead. Signed-off-by: Oleg Nesterov Acked-by: Srikar Dronamraju --- kernel/events/uprobes.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index f0d0453..604930b 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -610,6 +610,9 @@ __copy_insn(struct address_space *mapping, struct vm_area_struct *vma, char *ins if (!filp) return -EINVAL; + if (!mapping->a_ops->readpage) + return -EIO; + idx = (unsigned long)(offset >> PAGE_CACHE_SHIFT); off1 = offset &= ~PAGE_MASK; -- 1.5.5.1