From patchwork Sat Sep 11 10:28:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Len Baker X-Patchwork-Id: 12537673 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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 80F85C4332F for ; Sat, 11 Sep 2021 10:28:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 618E8611F2 for ; Sat, 11 Sep 2021 10:28:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235513AbhIKKaH (ORCPT ); Sat, 11 Sep 2021 06:30:07 -0400 Received: from mout.gmx.net ([212.227.17.20]:39781 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235443AbhIKKaH (ORCPT ); Sat, 11 Sep 2021 06:30:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gmx.net; s=badeba3b8450; t=1631356120; bh=kW2/XFCgLeQJ8pAdiZHbaLLR//IPNQFMApFkxDIZUaU=; h=X-UI-Sender-Class:From:To:Cc:Subject:Date; b=WBtsBZQz4G7/paKCTF08Zb5U1QgauCNKCCBvanb6wH1x9zXRmsbI68y2CmpVblb5/ DCnuY6avzo55meTZwHv0/vgqPtrkqRNlAJueAHSe7z0z6mkbUrN8Tc0pa0mzBN+uOi +zB3F/2TIfN6gn2kHWDi6e/S20kgBRV0pNu75rko= X-UI-Sender-Class: 01bb95c1-4bf8-414a-932a-4f6e2808ef9c Received: from localhost.localdomain ([79.150.72.99]) by mail.gmx.net (mrgmx105 [212.227.17.174]) with ESMTPSA (Nemesis) id 1M1Hdq-1mNMcU11P0-002rAx; Sat, 11 Sep 2021 12:28:40 +0200 From: Len Baker To: "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , Dexuan Cui , "David S. Miller" , Jakub Kicinski , Sumit Semwal , =?utf-8?q?Christian_K=C3=B6nig?= , Kees Cook Cc: Len Baker , Colin Ian King , linux-hardening@vger.kernel.org, linux-hyperv@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Subject: [PATCH] net: mana: Prefer struct_size over open coded arithmetic Date: Sat, 11 Sep 2021 12:28:18 +0200 Message-Id: <20210911102818.3804-1-len.baker@gmx.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Provags-ID: V03:K1:dfVEWPwUfXk7WIDTAbTGVLjgPLhUDRc24p6xewK3GBqzbU6DrcU ykjnc9cNedQlmlg2HsTJDh+pa11ahYb6Y+2sPn51SUs8CNYG+ggGvmOsFmGmQQ77r9/a55S 635XjyqZv/kz30sj90ZoUxbIdPhLVdwaip4p8XoRizgjtM4u7JfPsXt8t4JOwK4SDCTUtrm 5Pzh+wyuAZy8g7EzyPK9w== X-UI-Out-Filterresults: notjunk:1;V03:K0:aaZQKqUHAsA=:5UH7+Vp9zv9Ebwsos2eXEL B9iNcka0v4OG7PMubbF6LdznXb4ErFlO61hZEhq9oGgckm3FJ5cKWQ6bC5ipCTI2+MA4SK92W caQsjELrtMbv2QGtFTKiDEXjhOrnNwJuRtMXY7SnPFkDvfQzrhvrnXPE4k8Dl6wZDlpOssnnB 7Md6XCXwhXb8UkN+julAy9NVlC1bD2ntsojt+gzru8JEvgQKl+FEgmFC4rMiabvgWEFdpk6YT vSLGf110Znb6tr18K7NJuNP0gYe3Xf0QSIUt3X3dmhQ5Z28f1APyaDisfGrvg5McuOpxiriox oNr5gWttuw+wWB0KBjT6gy09FhBv8Wa2Snh1pHG2PKdqU6mYe0C5Lxk4TzHaDqVxye1tL6Pg7 dO28z09KUC+EIgw6S8XgCQBVx7dm6oRNWqciRZxWO/7JgTCbaueHrnYtvOhaAhWIFpqM829r0 9v8XeeePZO7B4DYIylStJa4mfNvq6jmLF5djc5DCcvi/gaTaiYD3vNk9/dXpq+TkKy/g+aEfA Z6A473KvK+Vk/6cFyb+9UUEWfvN82lv0L3ds3h/Al3c+OODzmxfT9D9a1G0PleRnBt6JqNAtW SlGpWhwEbBo57JGu09iPWi96i2Unng+YUswRioMXwko49w3MoRSAYVeTpADhUhm9OMqiD+gt1 P+zM/eLcG2vo5UJ9FHqsJrek28qAXjmH4bp/2yHajA97YalRzcXzUvcXMYhWTAIjPP5LyDbO8 Bm2/KgO8boMYnKYDBfPQczPSGkgDm6UD+aj6shCY9KfHj6iBLr98XGbnZYH715DHm8uN507bJ dnIZUXqBE9qkNQqSXlyiWymtlJinnByOgJeOwuaYYmUlnh9CRyb/k/plz86cTGBiEHUd+XDUr IZXEg0c18VaopPD1wCJHhpN1xg+lIsALJ+Mbg2hf5JutDHfznaK7mqEzMJkQYY+KejZyp6QZ9 w0e5Nmfb7xkg3Al2NYG9jcEpuQFRTQP6OWFcEP5lAySuU5Y2cRE5He88sy4DYYaRprCEbEmCo 4/aUvhJqiRUfnu8/v+kmZp/aNk2DG+fTaQnpzNkRq+yWLhCvmmS/gbJGYPrimhWlGMUk7KF3y 4tVhgpYCBw4awQ= Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org As noted in the "Deprecated Interfaces, Language Features, Attributes, and Conventions" documentation [1], size calculations (especially multiplication) should not be performed in memory allocator (or similar) function arguments due to the risk of them overflowing. This could lead to values wrapping around and a smaller allocation being made than the caller was expecting. Using those allocations could lead to linear overflows of heap memory and other misbehaviors. So, use the struct_size() helper to do the arithmetic instead of the argument "size + count * size" in the kzalloc() function. [1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments Signed-off-by: Len Baker Reviewed-by: Haiyang Zhang --- drivers/net/ethernet/microsoft/mana/hw_channel.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) -- 2.25.1 diff --git a/drivers/net/ethernet/microsoft/mana/hw_channel.c b/drivers/net/ethernet/microsoft/mana/hw_channel.c index 1a923fd99990..0efdc6c3c32a 100644 --- a/drivers/net/ethernet/microsoft/mana/hw_channel.c +++ b/drivers/net/ethernet/microsoft/mana/hw_channel.c @@ -398,9 +398,7 @@ static int mana_hwc_alloc_dma_buf(struct hw_channel_context *hwc, u16 q_depth, int err; u16 i; - dma_buf = kzalloc(sizeof(*dma_buf) + - q_depth * sizeof(struct hwc_work_request), - GFP_KERNEL); + dma_buf = kzalloc(struct_size(dma_buf, reqs, q_depth), GFP_KERNEL); if (!dma_buf) return -ENOMEM;