From nobody Mon Nov 10 12:45:34 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1556722132; cv=none; d=zoho.com; s=zohoarc; b=Bg8WItS1Gg4Pmh+N2K/zYy3bcxvHa52psL66jfElFtTkeesfAxyG9wLexPT2Fs+0lYLAFczUjrj2KzCCoqwb6lZLcv1oztVafuJAnigpZlL7u5vFyKu2603sdOG21lQ4PI5o4Qrs7O7wJV0YeJ53ltLXSS4VD5XKy9tFLGwqGHw= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1556722132; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To:ARC-Authentication-Results; bh=jWuGg9iKPGE2FiQOfN88ljkULaLlwzcKax7isfo1Sdc=; b=dvd4OIY3zSDLrNuLbU486vyYG0FcELfQAQ30zsVn7ww1H7h3BxgAjQ2j6aYcW9i/KKV18uHdpiRSrWRrnZdzvtHCtEBC/okgsAaJ0RTWoXFrZPW1qVN+A4A3wz302dKLIaWzBwyzIJ314c+I1OHTl8dhLi9hVwPaHCSUFDmqLuo= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1556722132423132.8431414538909; Wed, 1 May 2019 07:48:52 -0700 (PDT) Received: from localhost ([127.0.0.1]:60110 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hLqXL-0003Wm-AI for importer@patchew.org; Wed, 01 May 2019 10:48:43 -0400 Received: from eggs.gnu.org ([209.51.188.92]:54232) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hLqVe-0002fA-2j for qemu-devel@nongnu.org; Wed, 01 May 2019 10:47:01 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hLqVa-0001wS-DT for qemu-devel@nongnu.org; Wed, 01 May 2019 10:46:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35882) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hLqVa-0001vX-8R for qemu-devel@nongnu.org; Wed, 01 May 2019 10:46:54 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 98EF959451; Wed, 1 May 2019 14:46:50 +0000 (UTC) Received: from localhost.localdomain.com (ovpn-112-28.ams2.redhat.com [10.36.112.28]) by smtp.corp.redhat.com (Postfix) with ESMTP id D657A85882; Wed, 1 May 2019 14:46:48 +0000 (UTC) From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= To: qemu-devel@nongnu.org Date: Wed, 1 May 2019 15:46:46 +0100 Message-Id: <20190501144646.4851-1-berrange@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Wed, 01 May 2019 14:46:50 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH v2] linux-user: avoid string truncation warnings in uname field copying X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Riku Voipio , Laurent Vivier Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" In file included from /usr/include/string.h:494, from include/qemu/osdep.h:101, from linux-user/uname.c:20: In function =E2=80=98strncpy=E2=80=99, inlined from =E2=80=98sys_uname=E2=80=99 at linux-user/uname.c:94:3: /usr/include/bits/string_fortified.h:106:10: warning: =E2=80=98__builtin_st= rncpy=E2=80=99 output may be truncated copying 64 bytes from a string of le= ngth 64 [-Wstringop-truncation] 106 | return __builtin___strncpy_chk (__dest, __src, __len, __bos (__de= st)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~= ~~~~ We don't care where the NUL terminator in the original uname field was. It suffices to copy the entire original field and simply force a NUL terminator at the end of the new field. Signed-off-by: Daniel P. Berrang=C3=A9 Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- Changed in v2: - Always use sizeof() in preference to __NEW_UTS_LEN linux-user/uname.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/linux-user/uname.c b/linux-user/uname.c index 313b79dbad..1c05f95387 100644 --- a/linux-user/uname.c +++ b/linux-user/uname.c @@ -72,9 +72,8 @@ const char *cpu_to_uname_machine(void *cpu_env) =20 #define COPY_UTSNAME_FIELD(dest, src) \ do { \ - /* __NEW_UTS_LEN doesn't include terminating null */ \ - (void) strncpy((dest), (src), __NEW_UTS_LEN); \ - (dest)[__NEW_UTS_LEN] =3D '\0'; \ + memcpy((dest), (src), MIN(sizeof(src), sizeof(dest))); \ + (dest)[sizeof(dest) - 1] =3D '\0'; \ } while (0) =20 int sys_uname(struct new_utsname *buf) --=20 2.21.0