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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 CDC49C32789 for ; Fri, 2 Nov 2018 15:44:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8A58F20831 for ; Fri, 2 Nov 2018 15:44:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8A58F20831 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arndb.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727998AbeKCAwM (ORCPT ); Fri, 2 Nov 2018 20:52:12 -0400 Received: from mout.kundenserver.de ([212.227.126.130]:38253 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726229AbeKCAwM (ORCPT ); Fri, 2 Nov 2018 20:52:12 -0400 Received: from wuerfel.lan ([109.192.41.194]) by mrelayeu.kundenserver.de (mreue011 [212.227.15.129]) with ESMTPA (Nemesis) id 1MOzCW-1ftEZT48Ds-00PJNp; Fri, 02 Nov 2018 16:44:28 +0100 Received: from wuerfel.lan ([109.192.41.194]) by mrelayeu.kundenserver.de (mreue011 [212.227.15.129]) with ESMTPA (Nemesis) id 1MOzCW-1ftEZT48Ds-00PJNp; Fri, 02 Nov 2018 16:44:28 +0100 From: Arnd Bergmann To: Hannes Reinecke , "James E.J. Bottomley" , "Martin K. Petersen" Cc: Arnd Bergmann , James Bottomley , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] scsi: myrs: avoid stack overflow warning Date: Fri, 2 Nov 2018 16:44:13 +0100 Message-Id: <20181102154426.1951776-1-arnd@arndb.de> X-Mailer: git-send-email 2.18.0 X-Provags-ID: V03:K1:WPT/Ueqdsels/c/3nhc/ZnCHMhQZX/E1DafZp6Cw69G3O96kz2e n3+hIZ1lqoeiv0HTHUvAkt/jS7jwkA5AeOBPswXv+lUNEfTWu3KLTz2GdmXi5axe/PIGcVb uZfKjPe40mFAULsij7NAy9MadWCLIXyZhHukGeXJWWDs2M7ALovTFuyLYzNvMkjEIilHeGM uMZPZxm8PgVVNDCJNKr/g== X-UI-Out-Filterresults: notjunk:1;V01:K0:PaVVdk4xXzA=:HgKcRYpG4aNTtx05qg5jtw ABtmjGM316CNnQrY0+zosZyiaRwuTff4H8ehK8EljPyiLLJx95ZJ+6Xpz4ccDeY59xEqmGrR9 CFybR7HlP0uulWCeTHU9Rw+ORFWH9CkJsfunJbR1+b8AFYoIaI5nv2kqxsUfhUZrNoqiHOnfZ k45zX5J5c9SCng4xA3e8l4BmmpqUuREa4SOM6vjuHd9y2HPG23JJ3eJwtyUgGKtrNZkLnn2n/ jtdqu4jo+0+kLS7wbQC/SV1s4fVjPrp32m6zCWHYNPrn7wm4UZP/ql9FrYGExHYl+KfFM7XHe 0Mw9vf7E+HmOKkN53t6/0Hiso8VrGUlMHHvhL3G6eBW6QVpAbqJpilt6yhVTbpnBp03eF53Y3 mu9iZ9UbQ6G2ErVsRjo+HiQpXqTR1ego75Ot1Aj3jZq0ugq2zdxcM63zDQPhT1+m/v6P0XCO1 RPG6srb56alk2cguP3iEdvY2/NW7XanzSX7WgvSD0J0STbFJDhdiKdG4p5Tju8FKVkCiVKqeL jG532gEsdBgmUhHpJRf8E/ppiszcRN/UsQMGP2va+5NyTR2EicQobYMkXsixaETNecEfIWKbv 4P4mWcynnDXWmLftk+8pnjcKa2tZhwIN+fWA8tQsyMO5xGWsBB+ACTM3+3ZRXlHv5ZflQ9Pm5 mW3Pz6YnbzUZXyVX1FBt6T5wE5CtdzV7f4tfMbthcLjsVjgcNnd1BBEfChaLPpGMS0OqM3P54 4wZnAiIdbkw3tgXv7OuTspSjGJkpgANQR5B04NgZWAS+jxZGndtUj8Y7mgOvpg4pyi8KZc0Zd mmJdGYw Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Putting a 1024 byte data structure on the stack is generally a bad idea. On 32-bit systems, it also triggers a compile-time warning when building with -Og: drivers/scsi/myrs.c: In function 'myrs_get_ctlr_info': drivers/scsi/myrs.c:212:1: error: the frame size of 1028 bytes is larger than 1024 bytes [-Werror=frame-larger-than=] We only really need three members of the structure, so just read them manually here instead of copying the entire structure. Fixes: 77266186397c ("scsi: myrs: Add Mylex RAID controller (SCSI interface)") Signed-off-by: Arnd Bergmann --- drivers/scsi/myrs.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/scsi/myrs.c b/drivers/scsi/myrs.c index 0264a2e2bc19..b8d54ef8cf6d 100644 --- a/drivers/scsi/myrs.c +++ b/drivers/scsi/myrs.c @@ -163,9 +163,12 @@ static unsigned char myrs_get_ctlr_info(struct myrs_hba *cs) dma_addr_t ctlr_info_addr; union myrs_sgl *sgl; unsigned char status; - struct myrs_ctlr_info old; + unsigned short ldev_present, ldev_critical, ldev_offline; + + ldev_present = cs->ctlr_info->ldev_present; + ldev_critical = cs->ctlr_info->ldev_critical; + ldev_offline = cs->ctlr_info->ldev_offline; - memcpy(&old, cs->ctlr_info, sizeof(struct myrs_ctlr_info)); ctlr_info_addr = dma_map_single(&cs->pdev->dev, cs->ctlr_info, sizeof(struct myrs_ctlr_info), DMA_FROM_DEVICE); @@ -198,9 +201,9 @@ static unsigned char myrs_get_ctlr_info(struct myrs_hba *cs) cs->ctlr_info->rbld_active + cs->ctlr_info->exp_active != 0) cs->needs_update = true; - if (cs->ctlr_info->ldev_present != old.ldev_present || - cs->ctlr_info->ldev_critical != old.ldev_critical || - cs->ctlr_info->ldev_offline != old.ldev_offline) + if (cs->ctlr_info->ldev_present != ldev_present || + cs->ctlr_info->ldev_critical != ldev_critical || + cs->ctlr_info->ldev_offline != ldev_offline) shost_printk(KERN_INFO, cs->host, "Logical drive count changes (%d/%d/%d)\n", cs->ctlr_info->ldev_critical, -- 2.18.0