From patchwork Mon May 23 01:41:55 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: GUO Zihua X-Patchwork-Id: 12858394 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 62355C433F5 for ; Mon, 23 May 2022 01:43:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233689AbiEWBnq (ORCPT ); Sun, 22 May 2022 21:43:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37644 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232626AbiEWBnq (ORCPT ); Sun, 22 May 2022 21:43:46 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3CBC2201AC; Sun, 22 May 2022 18:43:44 -0700 (PDT) Received: from dggpemm500024.china.huawei.com (unknown [172.30.72.55]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4L60NL22GYzDqLY; Mon, 23 May 2022 09:38:42 +0800 (CST) Received: from huawei.com (10.67.175.31) by dggpemm500024.china.huawei.com (7.185.36.203) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Mon, 23 May 2022 09:43:31 +0800 From: GUO Zihua To: CC: , , , Subject: [PATCH v2] keys: Use struct_size and size_add helper with alloc Date: Mon, 23 May 2022 09:41:55 +0800 Message-ID: <20220523014155.27840-1-guozihua@huawei.com> X-Mailer: git-send-email 2.36.0 MIME-Version: 1.0 X-Originating-IP: [10.67.175.31] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemm500024.china.huawei.com (7.185.36.203) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org Use struct_size helper for calculating size of flexible struct, following the best practice. Reference: https://lore.kernel.org/all/CAHk-=wiGWjxs7EVUpccZEi6esvjpHJdgHQ=vtUeJ5crL62hx9A@mail.gmail.com/ Note: HASH_SIZE here is a SHA256_DIGEST_SIZE whoes value is 32, so adding 1 should be fine here. Signed-off-by: GUO Zihua Signed-off-by: GUO Zihua --- v2: Update the commit message, removing the part about "potential issue" following Jarkko's suggestion. --- security/keys/encrypted-keys/encrypted.c | 7 +++++-- security/keys/user_defined.c | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/security/keys/encrypted-keys/encrypted.c b/security/keys/encrypted-keys/encrypted.c index e05cfc2e49ae..37349580e855 100644 --- a/security/keys/encrypted-keys/encrypted.c +++ b/security/keys/encrypted-keys/encrypted.c @@ -613,6 +613,7 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, long dlen; int i; int ret; + size_t epayload_datalen = 0; ret = kstrtol(datalen, 10, &dlen); if (ret < 0 || dlen < MIN_DATA_SIZE || dlen > MAX_DATA_SIZE) @@ -667,8 +668,10 @@ static struct encrypted_key_payload *encrypted_key_alloc(struct key *key, if (ret < 0) return ERR_PTR(ret); - epayload = kzalloc(sizeof(*epayload) + payload_datalen + - datablob_len + HASH_SIZE + 1, GFP_KERNEL); + epayload_datalen = size_add(payload_datalen, datablob_len); + epayload_datalen = size_add(epayload_datalen, HASH_SIZE + 1); + epayload = kzalloc(struct_size(epayload, payload_data, + epayload_datalen), GFP_KERNEL); if (!epayload) return ERR_PTR(-ENOMEM); diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c index 749e2a4dcb13..334fed36e9f3 100644 --- a/security/keys/user_defined.c +++ b/security/keys/user_defined.c @@ -64,7 +64,7 @@ int user_preparse(struct key_preparsed_payload *prep) if (datalen <= 0 || datalen > 32767 || !prep->data) return -EINVAL; - upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL); + upayload = kmalloc(struct_size(upayload, data, datalen), GFP_KERNEL); if (!upayload) return -ENOMEM;