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[209.132.180.67]) by mx.google.com with ESMTP id d10si3588085pgf.910.2017.07.25.08.27.56; Tue, 25 Jul 2017 08:27:56 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752646AbdGYP1y (ORCPT + 26 others); Tue, 25 Jul 2017 11:27:54 -0400 Received: from mout.kundenserver.de ([212.227.17.24]:55055 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752144AbdGYP1x (ORCPT ); Tue, 25 Jul 2017 11:27:53 -0400 Received: from wuerfel.lan ([5.56.224.194]) by mrelayeu.kundenserver.de (mreue104 [212.227.15.145]) with ESMTPA (Nemesis) id 0LsywU-1dkW8t0FRa-012a58; Tue, 25 Jul 2017 17:27:41 +0200 From: Arnd Bergmann To: Andrey Ryabinin Cc: Arnd Bergmann , Dmitry Vyukov , Alexander Potapenko , Andrew Morton , Andrey Konovalov , Mark Rutland , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH] [v3] kasan: avoid -Wmaybe-uninitialized warning Date: Tue, 25 Jul 2017 17:27:29 +0200 Message-Id: <20170725152739.4176967-1-arnd@arndb.de> X-Mailer: git-send-email 2.9.0 X-Provags-ID: V03:K0:8Fr1N5CC6b3i4VA6XZ8gnbygr61ncv6KTSq7wItEWevkgp7EYbG yxTlkIKH0AnVe56z64gK04nEDRMRyBM/mIJojsnDCEdIwCoA0wsci2FT6rSDWzBBAUr+NWh YSFiiZNjH61UhXz4/ICNtmzFoKYBUdzpKTKyvBFaHeyqgYULMmx+yyWD7h6ylLUfD9TfN8m 8RW2Ghlt/2JyR79EUvfgg== X-UI-Out-Filterresults: notjunk:1; V01:K0:oXAiT7yTdvc=:5IYwKgGJCdobg8eO0M0MlF omB5NoGkr5IcNO/eKPAlZnpKZSwZ8ihNpdnLE9PT4wxZAusxigOQOy+9haT1gUG3Uq/igNDj1 jYMSUeaMNObYtO8Ebtb8WrGJjpdkQa5rFtDOXWRfDI3oMydynZ4TodL89BeWD4p/d5RZaL8IS NGg/jj+Hbw/FPLlWRtSOWcstev0dtJf1sgtCr9wOSYRGnNS5Rg/RwJkDDpcDgcYMSQEUbuoGJ zu3GKBcVgLR7/obus5SDBnyXTIPHsyymtojSoOA+at8LhWDoLHHFLejtnBYVAnx7F7MoMuqaq UlKKrUsK0lTd5krY/UwIsU9ujA36QWWFjB/lwpbmSQ6Ye6t/H/CN1yZcs4QcbdVOGrB83YO7o sSGf3iiASoLn9pVbhr6P83UsKJjLcNWiudn+N0KiTbmWCJTqVNI7ED4FwULE98uIOUg+7c1sS l2552/7fLWe+KZmA5V4OEwSgf28AAqDt2Q4l86KvovkPEipNx1gzFchp68Fs/Yvvj49GAcbW6 BMMdsv2RxkRsZYv1k5N/fEAaDTSzC+qV9y/toPMr3taqxokoI5hzBVoHauhu7nIEnlCy2G4hR Jbh4xDrJOx/lG1rGn1VpEb/pKb7I3cFbxTpEmHHxODNy7TPwmYjgONTVf5LCYkKlV/thblxXQ IbqgmKkrY4LZ6K7tYmyGfq4ultQJ8b34lvQQCWIkRJhXiAj/O1SiFpEIZGZjzhOj1aedQpBmU geLg2dN02xQ9o7gSAaIgvE7HlMVJ0exa8Vea/Q== Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org gcc-7 produces this warning: mm/kasan/report.c: In function 'kasan_report': mm/kasan/report.c:351:3: error: 'info.first_bad_addr' may be used uninitialized in this function [-Werror=maybe-uninitialized] print_shadow_for_address(info->first_bad_addr); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ mm/kasan/report.c:360:27: note: 'info.first_bad_addr' was declared here The code seems fine as we only print info.first_bad_addr when there is a shadow, and we always initialize it in that case, but this is relatively hard for gcc to figure out after the latest rework. Adding an intialization to the most likely value together with the other struct members shuts up that warning. Fixes: b235b9808664 ("kasan: unify report headers") Link: https://patchwork.kernel.org/patch/9641417/ Suggested-by: Alexander Potapenko Suggested-by: Andrey Ryabinin Cc: Dmitry Vyukov Signed-off-by: Arnd Bergmann --- Originally submitted on March 23, but unfortunately is still needed, as verified on 4.13-rc1, with aarch64-linux-gcc-7.1.1 v2: add a comment as Andrew suggested v3: move initialization as Alexander and Andrey suggested --- mm/kasan/report.c | 1 + 1 file changed, 1 insertion(+) -- 2.9.0 Acked-by: Andrey Ryabinin diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 04bb1d3eb9ec..6bcfb01ba038 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -401,6 +401,7 @@ void kasan_report(unsigned long addr, size_t size, disable_trace_on_warning(); info.access_addr = (void *)addr; + info.first_bad_addr = (void *)addr; info.access_size = size; info.is_write = is_write; info.ip = ip;