From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933424AbcI1WzL (ORCPT ); Wed, 28 Sep 2016 18:55:11 -0400 Received: from thejh.net ([37.221.195.125]:52523 "EHLO thejh.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753162AbcI1Wy4 (ORCPT ); Wed, 28 Sep 2016 18:54:56 -0400 From: Jann Horn To: security@kernel.org, Alexander Viro , Paul Moore , Stephen Smalley , Eric Paris , James Morris , "Serge E. Hallyn" Cc: Nick Kralevich , Janis Danisevskis , linux-security-module@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/3] fs/exec: don't force writing memory access Date: Thu, 29 Sep 2016 00:54:39 +0200 Message-Id: <1475103281-7989-2-git-send-email-jann@thejh.net> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1475103281-7989-1-git-send-email-jann@thejh.net> References: <1475103281-7989-1-git-send-email-jann@thejh.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This shouldn't change behavior in any way - at this point, there should be no non-writable mappings, only the initial stack mapping -, but this change makes it easier to reason about the correctness of the following commits that place restrictions on forced memory writes. Signed-off-by: Jann Horn Reviewed-by: Janis Danisevskis --- fs/exec.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/exec.c b/fs/exec.c index 6fcfb3f..d607da8 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -204,7 +204,7 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos, * doing the exec and bprm->mm is the new process's mm. */ ret = get_user_pages_remote(current, bprm->mm, pos, 1, write, - 1, &page, NULL); + 0, &page, NULL); if (ret <= 0) return NULL; -- 2.1.4