From patchwork Mon Jun 14 10:27:06 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 460362 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 228F4C48BE8 for ; Mon, 14 Jun 2021 10:53:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D6AB619AE for ; Mon, 14 Jun 2021 10:53:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234015AbhFNKzc (ORCPT ); Mon, 14 Jun 2021 06:55:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:58832 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234575AbhFNKxZ (ORCPT ); Mon, 14 Jun 2021 06:53:25 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3D3036148E; Mon, 14 Jun 2021 10:39:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1623667190; bh=VHAXdjdcllNCvOk3Jm+KgEHu0Sx0iGudak86gchl8V8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=G/eh3Mx36bEIlXHwjl8WwO5AWoTCIuYnfGkAp0fZQlsSJ0a4T6BzbvSYH4UyCKskE ynYxNnyZ8fbM+D7FtN3LAgERYVusTWlYnyyOhWKoHHz6QLBwL+5erbtKvOG8yMndwn L5NMDkFE1sPZrvqbblhNFAys3WKf+dHfrcB7Il+0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, John Keeping , Mike Snitzer , Sasha Levin Subject: [PATCH 5.4 28/84] dm verity: fix require_signatures module_param permissions Date: Mon, 14 Jun 2021 12:27:06 +0200 Message-Id: <20210614102647.311916724@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210614102646.341387537@linuxfoundation.org> References: <20210614102646.341387537@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: John Keeping [ Upstream commit 0c1f3193b1cdd21e7182f97dc9bca7d284d18a15 ] The third parameter of module_param() is permissions for the sysfs node but it looks like it is being used as the initial value of the parameter here. In fact, false here equates to omitting the file from sysfs and does not affect the value of require_signatures. Making the parameter writable is not simple because going from false->true is fine but it should not be possible to remove the requirement to verify a signature. But it can be useful to inspect the value of this parameter from userspace, so change the permissions to make a read-only file in sysfs. Signed-off-by: John Keeping Signed-off-by: Mike Snitzer Signed-off-by: Sasha Levin --- drivers/md/dm-verity-verify-sig.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/md/dm-verity-verify-sig.c b/drivers/md/dm-verity-verify-sig.c index 614e43db93aa..919154ae4cae 100644 --- a/drivers/md/dm-verity-verify-sig.c +++ b/drivers/md/dm-verity-verify-sig.c @@ -15,7 +15,7 @@ #define DM_VERITY_VERIFY_ERR(s) DM_VERITY_ROOT_HASH_VERIFICATION " " s static bool require_signatures; -module_param(require_signatures, bool, false); +module_param(require_signatures, bool, 0444); MODULE_PARM_DESC(require_signatures, "Verify the roothash of dm-verity hash tree");