From patchwork Thu Jul 9 06:19:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tyler Hicks X-Patchwork-Id: 11653419 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 26DEA618 for ; Thu, 9 Jul 2020 06:20:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 03D0B20672 for ; Thu, 9 Jul 2020 06:20:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="g7f7y5H5" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726774AbgGIGUg (ORCPT ); Thu, 9 Jul 2020 02:20:36 -0400 Received: from linux.microsoft.com ([13.77.154.182]:38096 "EHLO linux.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726581AbgGIGUM (ORCPT ); Thu, 9 Jul 2020 02:20:12 -0400 Received: from sequoia.work.tihix.com (162-237-133-238.lightspeed.rcsntx.sbcglobal.net [162.237.133.238]) by linux.microsoft.com (Postfix) with ESMTPSA id ED52220B4909; Wed, 8 Jul 2020 23:20:10 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com ED52220B4909 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1594275611; bh=kdGo+g0Ug/+ndalVCdzuX/XIssnW7sZa5n/LdXUX1OM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=g7f7y5H5XpYSW/JqRJeaI3n/zw1XVmSYLKBZA3ZBwjh3RAvvCTvC6hDloRL5oNLGT 1ZTeusQjwRyMyX8hLF/RbnyRh9kx0ArCJoWQVWs8CB3V3xt6qevpWkxEMjlG2rTIiD MerMF1DJfyii9F7c6vAGHXSWuZtO3sf2EjsznJx8= From: Tyler Hicks To: Mimi Zohar , Dmitry Kasatkin Cc: James Morris , "Serge E . Hallyn" , Lakshmi Ramasubramanian , Prakhar Srivastava , linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org Subject: [PATCH v3 08/12] ima: Shallow copy the args_p member of ima_rule_entry.lsm elements Date: Thu, 9 Jul 2020 01:19:07 -0500 Message-Id: <20200709061911.954326-9-tyhicks@linux.microsoft.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200709061911.954326-1-tyhicks@linux.microsoft.com> References: <20200709061911.954326-1-tyhicks@linux.microsoft.com> MIME-Version: 1.0 Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: The args_p member is a simple string that is allocated by ima_rule_init(). Shallow copy it like other non-LSM references in ima_rule_entry structs. There are no longer any necessary error path cleanups to do in ima_lsm_copy_rule(). Signed-off-by: Tyler Hicks Reviewed-by: Konsta Karsisto --- * v3 - No change * v2 - Adjusted context to account for ima_lsm_copy_rule() directly calling ima_lsm_free_rule() and the lack of explicit reference ownership transfers - Added comment to ima_lsm_copy_rule() to document the args_p reference ownership transfer security/integrity/ima/ima_policy.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c index 9842e2e0bc6d..b02e1ffd10c9 100644 --- a/security/integrity/ima/ima_policy.c +++ b/security/integrity/ima/ima_policy.c @@ -300,10 +300,13 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) continue; nentry->lsm[i].type = entry->lsm[i].type; - nentry->lsm[i].args_p = kstrdup(entry->lsm[i].args_p, - GFP_KERNEL); - if (!nentry->lsm[i].args_p) - goto out_err; + nentry->lsm[i].args_p = entry->lsm[i].args_p; + /* + * Remove the reference from entry so that the associated + * memory will not be freed during a later call to + * ima_lsm_free_rule(entry). + */ + entry->lsm[i].args_p = NULL; security_filter_rule_init(nentry->lsm[i].type, Audit_equal, @@ -314,11 +317,6 @@ static struct ima_rule_entry *ima_lsm_copy_rule(struct ima_rule_entry *entry) (char *)entry->lsm[i].args_p); } return nentry; - -out_err: - ima_lsm_free_rule(nentry); - kfree(nentry); - return NULL; } static int ima_lsm_update_rule(struct ima_rule_entry *entry)