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=-8.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 14E6FC433B4 for ; Sat, 17 Apr 2021 18:02:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E406861026 for ; Sat, 17 Apr 2021 18:02:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236899AbhDQSCs (ORCPT ); Sat, 17 Apr 2021 14:02:48 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:43282 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236799AbhDQSCr (ORCPT ); Sat, 17 Apr 2021 14:02:47 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1618682540; h=Date: Message-Id: Cc: To: References: In-Reply-To: From: Subject: Content-Transfer-Encoding: MIME-Version: Content-Type: Sender; bh=C3QnJoRSnhvDwC+6O1+r8DxZ/vXB9t7O2U1Bylb6Rkc=; b=StFR3ufg3NbtgiRd2eTFv2QFw9W1LPjpiEJm5mf84wuzLgbs20BP+bbKN782+Q/ID93kPJVT AznLrXjY36kGhyW26dIfWkF60Jm827Yru1osQ7A7ksigM5BeW5rkB1sIzX6/5wu0vYmwyhBc gcuJIPYPk4hlaMEVw5SaRVIu3vg= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI3YTAwOSIsICJsaW51eC13aXJlbGVzc0B2Z2VyLmtlcm5lbC5vcmciLCAiYmU5ZTRhIl0= Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-west-2.postgun.com with SMTP id 607b22ab215b831afb35509c (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Sat, 17 Apr 2021 18:02:19 GMT Sender: kvalo=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 6A4D0C43460; Sat, 17 Apr 2021 18:02:19 +0000 (UTC) Received: from potku.adurom.net (88-114-240-156.elisa-laajakaista.fi [88.114.240.156]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: kvalo) by smtp.codeaurora.org (Postfix) with ESMTPSA id 786E1C433F1; Sat, 17 Apr 2021 18:02:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 786E1C433F1 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=kvalo@codeaurora.org Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: Re: [PATCH net-next] wlcore: fix overlapping snprintf arguments in debugfs From: Kalle Valo In-Reply-To: <20210323125723.1961432-1-arnd@kernel.org> References: <20210323125723.1961432-1-arnd@kernel.org> To: Arnd Bergmann Cc: "David S. Miller" , Jakub Kicinski , Luciano Coelho , Arik Nemtsov , Arnd Bergmann , Lee Jones , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org User-Agent: pwcli/0.1.0-git (https://github.com/kvalo/pwcli/) Python/3.5.2 Message-Id: <20210417180219.6A4D0C43460@smtp.codeaurora.org> Date: Sat, 17 Apr 2021 18:02:19 +0000 (UTC) Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Arnd Bergmann wrote: > From: Arnd Bergmann > > gcc complains about undefined behavior in calling snprintf() > with the same buffer as input and output: > > drivers/net/wireless/ti/wl18xx/debugfs.c: In function 'diversity_num_of_packets_per_ant_read': > drivers/net/wireless/ti/wl18xx/../wlcore/debugfs.h:86:3: error: 'snprintf' argument 4 overlaps destination object 'buf' [-Werror=restrict] > 86 | snprintf(buf, sizeof(buf), "%s[%d] = %d\n", \ > | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > 87 | buf, i, stats->sub.name[i]); \ > | ~~~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/wireless/ti/wl18xx/debugfs.c:24:2: note: in expansion of macro 'DEBUGFS_FWSTATS_FILE_ARRAY' > 24 | DEBUGFS_FWSTATS_FILE_ARRAY(a, b, c, wl18xx_acx_statistics) > | ^~~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/net/wireless/ti/wl18xx/debugfs.c:159:1: note: in expansion of macro 'WL18XX_DEBUGFS_FWSTATS_FILE_ARRAY' > 159 | WL18XX_DEBUGFS_FWSTATS_FILE_ARRAY(diversity, num_of_packets_per_ant, > > There are probably other ways of handling the debugfs file, without > using on-stack buffers, but a simple workaround here is to remember the > current position in the buffer and just keep printing in there. > > Fixes: bcca1bbdd412 ("wlcore: add debugfs macro to help print fw statistics arrays") > Signed-off-by: Arnd Bergmann Patch applied to wireless-drivers-next.git, thanks. 7b0e2c4f6be3 wlcore: fix overlapping snprintf arguments in debugfs -- https://patchwork.kernel.org/project/linux-wireless/patch/20210323125723.1961432-1-arnd@kernel.org/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches