From mboxrd@z Thu Jan 1 00:00:00 1970 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 7E44CC433FE for ; Tue, 17 May 2022 21:26:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230153AbiEQV0s (ORCPT ); Tue, 17 May 2022 17:26:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229469AbiEQV0q (ORCPT ); Tue, 17 May 2022 17:26:46 -0400 Received: from mail-pj1-x1030.google.com (mail-pj1-x1030.google.com [IPv6:2607:f8b0:4864:20::1030]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A095251E52 for ; Tue, 17 May 2022 14:26:45 -0700 (PDT) Received: by mail-pj1-x1030.google.com with SMTP id l7-20020a17090aaa8700b001dd1a5b9965so101686pjq.2 for ; Tue, 17 May 2022 14:26:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=qLJg95t8R5cMqLU8BKOAsIibZzXFsrk9MeOVY0EHh98=; b=Zy3T4x476IYScnuQ4oQveqRGMhLKJZVxMoLu6uG6d99FerUglj29HdwnGrQ+ta7Q6O r6DA5/nGpi5QjRJppqsqbHpjqlifbw9JLXPNJj3p7XTLhBzsQnwi68BZX9dApNZ3+vpY G3wreieQn48yEHwfa0dh7kGMSGRHDFp33MbT4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=qLJg95t8R5cMqLU8BKOAsIibZzXFsrk9MeOVY0EHh98=; b=CVciY+u/PET9Q7/Z5AP/mmTlRLK+FLCH3DyWjeAmu84eBxLCpcd9DyvYfd4W7ZTt+M nP0LN2d6GAmrGsZx5qvjQXj5pN+hSQjLdU63beLpZDl76f6Vs/WDsXTWOvPGJHLRqvdn GeybHmeojCHo3QYWeYKdzj21qmi9Bzt0/CyQNC1YEmgCL8ADNpO7vj89H+Y7kKd7OhGY P4T/hrwsRUKlTKFut0Sk5i4mCdbS8fI6eo2iiFuPsZZNSXPjnGC00jx0ezWi6LN92tqL CotUmlPbMh4pfNIeC3TTovTMz7qyjp9c8w76b/0IyW1QyqTlWWtQY5+oM7sAss99Wzre 3RHw== X-Gm-Message-State: AOAM530UQm//jzwSQTSSJ90ehAMeYk/cICGqFvYFYiIdKsSIxtl2Afus M6nw8cw+btu5qtsvAXTCE0v9yQ== X-Google-Smtp-Source: ABdhPJw4YmKS8zJYnuDLhmLwpfwUIROVB9p9nPBNDBDH2YBY5Eqmnikjrzy/efi8Ky4G7rfprcjTmw== X-Received: by 2002:a17:902:f542:b0:15e:b6d2:88d9 with SMTP id h2-20020a170902f54200b0015eb6d288d9mr23741493plf.128.1652822805160; Tue, 17 May 2022 14:26:45 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id l1-20020a170902ec0100b0015e8d4eb267sm70065pld.177.2022.05.17.14.26.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 17 May 2022 14:26:44 -0700 (PDT) Date: Tue, 17 May 2022 14:26:44 -0700 From: Kees Cook To: GUO Zihua Cc: keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, davem@davemloft.net, dhowells@redhat.com, herbert@gondor.apana.org.au, gustavoars@kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] crypto: Use struct_size() helper in kmalloc() Message-ID: <202205171424.CF36CE58@keescook> References: <20220517080532.31015-1-guozihua@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220517080532.31015-1-guozihua@huawei.com> Precedence: bulk List-ID: X-Mailing-List: keyrings@vger.kernel.org On Tue, May 17, 2022 at 04:05:32PM +0800, GUO Zihua wrote: > Make use of struct_size() heler for structures containing flexible array > member instead of sizeof() which prevents potential issues as well as > addressing the following sparse warning: > > crypto/asymmetric_keys/asymmetric_type.c:155:23: warning: using sizeof > on a flexible structure > crypto/asymmetric_keys/asymmetric_type.c:247:28: warning: using sizeof > on a flexible structure > > Reference: https://github.com/KSPP/linux/issues/174 > > Signed-off-by: GUO Zihua > --- > crypto/asymmetric_keys/asymmetric_type.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c > index 41a2f0eb4ce4..96a99a91bf17 100644 > --- a/crypto/asymmetric_keys/asymmetric_type.c > +++ b/crypto/asymmetric_keys/asymmetric_type.c > @@ -152,7 +152,7 @@ struct asymmetric_key_id *asymmetric_key_generate_id(const void *val_1, > { > struct asymmetric_key_id *kid; > > - kid = kmalloc(sizeof(struct asymmetric_key_id) + len_1 + len_2, > + kid = kmalloc(struct_size(kid, data, len_1 + len_2), Please use the size_add() helper for this open-coded add here. > GFP_KERNEL); > if (!kid) > return ERR_PTR(-ENOMEM); > @@ -244,7 +244,7 @@ struct asymmetric_key_id *asymmetric_key_hex_to_key_id(const char *id) > if (asciihexlen & 1) > return ERR_PTR(-EINVAL); > > - match_id = kmalloc(sizeof(struct asymmetric_key_id) + asciihexlen / 2, > + match_id = kmalloc(struct_size(match_id, data, asciihexlen / 2), There is no size_div(), but that's ok here because the denominator is an constant expression. > GFP_KERNEL); > if (!match_id) > return ERR_PTR(-ENOMEM); > -- > 2.36.0 > -- Kees Cook