From patchwork Sat Jun 20 03:30:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kees Cook X-Patchwork-Id: 11615447 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BB4AE14E3 for ; Sat, 20 Jun 2020 03:30:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 883382073E for ; Sat, 20 Jun 2020 03:30:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="NXIjEZzm" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 883382073E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 42BAF6B00A6; Fri, 19 Jun 2020 23:30:27 -0400 (EDT) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id 38C256B00A7; Fri, 19 Jun 2020 23:30:27 -0400 (EDT) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 203396B00A8; Fri, 19 Jun 2020 23:30:27 -0400 (EDT) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0172.hostedemail.com [216.40.44.172]) by kanga.kvack.org (Postfix) with ESMTP id EC5CB6B00A6 for ; Fri, 19 Jun 2020 23:30:26 -0400 (EDT) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id ADAB61EE6 for ; Sat, 20 Jun 2020 03:30:26 +0000 (UTC) X-FDA: 76948162452.03.wash72_400691226e1e Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin03.hostedemail.com (Postfix) with ESMTP id 8A48A28A4E8 for ; Sat, 20 Jun 2020 03:30:26 +0000 (UTC) X-Spam-Summary: 2,0,0,326ba75c8a589cb6,d41d8cd98f00b204,keescook@chromium.org,,RULES_HIT:41:355:379:541:800:960:967:968:973:988:989:1260:1311:1314:1345:1437:1515:1535:1542:1711:1730:1747:1777:1792:2393:2525:2559:2566:2570:2682:2685:2703:2859:2933:2937:2939:2942:2945:2947:2951:2954:3022:3352:3865:3866:3867:3868:3870:3871:3872:3934:3936:3938:3941:3944:3947:3950:3953:3956:3959:4321:4605:5007:6261:7875:8957:9025:10004:11658:13149:13230,0,RBL:209.85.210.195:@chromium.org:.lbl8.mailshell.net-66.100.201.201 62.2.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fp,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: wash72_400691226e1e X-Filterd-Recvd-Size: 5492 Received: from mail-pf1-f195.google.com (mail-pf1-f195.google.com [209.85.210.195]) by imf38.hostedemail.com (Postfix) with ESMTP for ; Sat, 20 Jun 2020 03:30:26 +0000 (UTC) Received: by mail-pf1-f195.google.com with SMTP id x22so5383831pfn.3 for ; Fri, 19 Jun 2020 20:30:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=7ExlyNd4C6Vtqo5InL4xGzXnaPAWUSdxdUBoxlRz8EM=; b=NXIjEZzmAlY5fdC/DwXct9GYDHogfeUCrjSkTO4JXjF9UTv+cR2dEUWt3FWlTNaAHp ArVHLS7GaAaX0GRdppC6MVL4iulBAnXl0RDRkmjEpohR99AIp9TcfcZKNXy8KweQ5j+M qKbddjlMm6r/UiOtSlPQhvc966Inhn9BIPgP4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=7ExlyNd4C6Vtqo5InL4xGzXnaPAWUSdxdUBoxlRz8EM=; b=aBph7B3a+5+VxlXtFUQ9uIMVt1L3iLP3+UOD2NY5VHWLhBMHm0Ir6WWrbOeEdwe0Y4 YkfcDfanIrv7kGcdNNNMSX015nNEqKGsee7+2X7G2loPXhpCFWauELPQJ/V6sqEuPEEl OMeamfmz0kK30wUUYDwKL5lgYZ7lSv7l15BwfjkdQ2bywTcLPb1paWXxiGX0UQ5Zjz1S 8b2ke0pMHgfSQrEh0SgS4g8vVm9qhzTh0/v9T65hAFIhG8giBO4QocwgqSJC0ARhwbdS Fq39PFXzMglkruH0VMSg1EP1L7wGmoxUC9q0dqSX3vdZZU5RDgT264TiFRH8vjmyyYgO M6ig== X-Gm-Message-State: AOAM533zN2Vkb2A0ORUQcIeDA5JD5EUQOlMjimNPJglaYTokc1KmNNqa jLT9tqfBl+2Q9Cav3SNc2w5SSQ== X-Google-Smtp-Source: ABdhPJyAJ8Da6kpj1cpdp7acRpdjHPEasdxnBrzutMhIZjw6K4AKJtCbSzx12+H3IHWiTttzpZGpTg== X-Received: by 2002:a63:dd42:: with SMTP id g2mr5615212pgj.442.1592623825373; Fri, 19 Jun 2020 20:30:25 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id n69sm7060385pjc.25.2020.06.19.20.30.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Jun 2020 20:30:20 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Linus Torvalds , Miguel Ojeda , Alexander Potapenko , Joe Perches , Andy Whitcroft , x86@kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org, linux-clk@vger.kernel.org, linux-spi@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com Subject: [PATCH v2 11/16] media: sur40: Remove uninitialized_var() usage Date: Fri, 19 Jun 2020 20:30:02 -0700 Message-Id: <20200620033007.1444705-12-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200620033007.1444705-1-keescook@chromium.org> References: <20200620033007.1444705-1-keescook@chromium.org> MIME-Version: 1.0 X-Rspamd-Queue-Id: 8A48A28A4E8 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam03 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. As a precursor to removing[2] this[3] macro[4], just remove this variable since it was actually unused: drivers/input/touchscreen/sur40.c:459:6: warning: variable 'packet_id' set but not used [-Wunused-but-set-variable] 459 | u32 packet_id; | ^~~~~~~~~ However, in keeping with the documentation desires outlined in commit 335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output"), comment out the assignment instead of removing it. [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Fixes: 335abaea7a27 ("Input: sur40 - silence unnecessary noisy debug output") Signed-off-by: Kees Cook Reviewed-by: Nick Desaulniers --- drivers/input/touchscreen/sur40.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c index 34d31c7ec8ba..620cdd7d214a 100644 --- a/drivers/input/touchscreen/sur40.c +++ b/drivers/input/touchscreen/sur40.c @@ -456,8 +456,6 @@ static void sur40_poll(struct input_dev *input) { struct sur40_state *sur40 = input_get_drvdata(input); int result, bulk_read, need_blobs, packet_blobs, i; - u32 uninitialized_var(packet_id); - struct sur40_header *header = &sur40->bulk_in_buffer->header; struct sur40_blob *inblob = &sur40->bulk_in_buffer->blobs[0]; @@ -491,7 +489,7 @@ static void sur40_poll(struct input_dev *input) if (need_blobs == -1) { need_blobs = le16_to_cpu(header->count); dev_dbg(sur40->dev, "need %d blobs\n", need_blobs); - packet_id = le32_to_cpu(header->packet_id); + /* packet_id = le32_to_cpu(header->packet_id); */ } /*