From nobody Thu Nov 13 21:53:35 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.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; dkim=fail; spf=pass (zohomail.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=gmail.com ARC-Seal: i=1; a=rsa-sha256; t=1583090329; cv=none; d=zohomail.com; s=zohoarc; b=gV1zA7rmtGRpvgk7W1rYUnEKFt3Ffb4eID08TranyUPx9vga0lfFOmGMGmUAkeBnYHTZEaBdYQ5yko1axaEB948+t+CTK5BQ61x1g+78IjWwEJvZjSXn1H48Z8yVFi1pujgoMlTdebs76UXMcPY6oL/YJUDs7km0Y+MeEJmZ7Io= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1583090329; 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; bh=z5hv8NKRgwZBSYnKj83xWQNko+acePoToJbKL4ekO/Q=; b=ma7s6cMKWSZsCjDat6xPCdyYwu6nZF3InF3h+U3zAKKVtSYQeaPDT4Dn0IGU9fIkv+XkI5sC/qilfItYOnorAtb3otutyCsv/WDWFvT61hOJj3kMoApONDHakVaR2osnaftYNBcxV4WxFiTK4bAMNwPBfZpz9DPwNoNhHursEE8= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=fail; spf=pass (zohomail.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 1583090329948904.017641779192; Sun, 1 Mar 2020 11:18:49 -0800 (PST) Received: from localhost ([::1]:51222 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8U6x-0005PN-Tr for importer@patchew.org; Sun, 01 Mar 2020 14:18:47 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:42825) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1j8U5T-0004g8-5K for qemu-devel@nongnu.org; Sun, 01 Mar 2020 14:17:16 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1j8U5S-0005VH-3x for qemu-devel@nongnu.org; Sun, 01 Mar 2020 14:17:15 -0500 Received: from mail-qv1-xf44.google.com ([2607:f8b0:4864:20::f44]:44686) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1j8U5R-0005V7-Ub for qemu-devel@nongnu.org; Sun, 01 Mar 2020 14:17:14 -0500 Received: by mail-qv1-xf44.google.com with SMTP id b13so1399430qvt.11 for ; Sun, 01 Mar 2020 11:17:13 -0800 (PST) Received: from localhost.localdomain ([2804:431:c7cb:f65:3196:5ed7:3478:df97]) by smtp.gmail.com with ESMTPSA id w60sm8773171qte.39.2020.03.01.11.17.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 01 Mar 2020 11:17:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=z5hv8NKRgwZBSYnKj83xWQNko+acePoToJbKL4ekO/Q=; b=n6lUqXBqWKcuvZME/0epxSx1ghHS36muuNYclYZmr5MMFNDmF3gsxFZf4+7PLGhwmh +2A782B73hdRzASzxd4msO3PzgpqP/FRpGEBX7HSjK1ekAsmyKyDolqtY1wVso/D5uwb V4rE6d+JKBuwPqkOvAJEVbo9vq5mbPf8zTB745dv1fIZsMQxsK4edgOljKycelIpZyr4 vkBs9L/VTRFPIaYC9/F9eSkQiPppa7fuJSpwyRx+J0IS0oW6qv8lDZwW3yrGGelsiQF5 R6a9K2l9KdHfe+DwQ/gNNtiBaANBsE8wM79c9JxtmpWtzAIyLEb6qF/LChpQDBRzcRh5 wbDQ== 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:mime-version :content-transfer-encoding; bh=z5hv8NKRgwZBSYnKj83xWQNko+acePoToJbKL4ekO/Q=; b=PhFuLYw4Y8eGEfJb07JpL8YrVbHDHthHnTIApTsN1LnCzl1nhZoezXlVxhpM423ruP hSzOKgLssEKJc+udJpwPs8JvZg5ozVJwXlPsSvmJ9fBxAPhjTfhYKFea4LQE3ewvgpfc GKPL2I+sgufwT2aE7TpgieygSEQ1B1Gda6hYuOYbTJriJNk90n6zEwB2sU/gf11iuXLg htFP/qqX2nIymwEp40tjFvQxX0+oqFMB7hx9mSS/cwnIAb9XuYPDQVspSYXWDAlgZN94 upL+WXtSXDV7FBfof8J7UDQHRTC0cCQuj6nKWGzVYBWsLw7swv0+V/L5qCHst0psn7KW Kdgw== X-Gm-Message-State: ANhLgQ3RDcIGgQ7Gw9v96MliBI6AsOeJWKaGmT0WcpO3uWBBU0Q2GV68 mc2iyXT7j3Yeu19vHv2KVvRl6eBm X-Google-Smtp-Source: ADFU+vuOsX2bDdWt4G2SRXGnzoZSbEloa7V0jFu3pfO3IxHgN9ZEmhhepnXY1hyJASbcld8+i+A+bw== X-Received: by 2002:a05:6214:294:: with SMTP id l20mr2509685qvv.28.1583090232664; Sun, 01 Mar 2020 11:17:12 -0800 (PST) From: Julio Faracco To: qemu-devel@nongnu.org Subject: [PATCH v2] i386: Fix GCC warning with snprintf when HAX is enabled Date: Sun, 1 Mar 2020 16:17:08 -0300 Message-Id: <20200301191708.18035-1-jcfaracco@gmail.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::f44 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Eduardo Habkost , Richard Henderson Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) When HAX is enabled (--enable-hax), GCC 9.2.1 reports issues with snprintf(). This commit is checking if snprintf returns an error. This is a simple way to avoid this warnings. An `assert()` boundary checks were added before snprintf too. For more details, one example of warning: CC i386-softmmu/target/i386/hax-posix.o qemu/target/i386/hax-posix.c: In function =E2=80=98hax_host_open_vm=E2=80= =99: qemu/target/i386/hax-posix.c:124:56: error: =E2=80=98%02d=E2=80=99 directiv= e output may be truncated writing between 2 and 11 bytes into a region of size 3 [-Werror=3Dformat-truncation=3D] 124 | snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id= ); | ^~~~ qemu/target/i386/hax-posix.c:124:41: note: directive argument in the range [-2147483648, 64] 124 | snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id= ); | ^~~~~~~~~~~~~~~~~~~~ In file included from /usr/include/stdio.h:867, from qemu/include/qemu/osdep.h:99, from qemu/target/i386/hax-posix.c:14: /usr/include/bits/stdio2.h:67:10: note: =E2=80=98__builtin___snprintf_chk= =E2=80=99 output between 17 and 26 bytes into a destination of size 17 67 | return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - = 1, | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~= ~~ 68 | __bos (__s), __fmt, __va_arg_pack ()); | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Signed-off-by: Julio Faracco --- v1-v2: Add assert() as Richard Henderson suggested. --- target/i386/hax-posix.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/target/i386/hax-posix.c b/target/i386/hax-posix.c index a5426a6dac..dc777751d7 100644 --- a/target/i386/hax-posix.c +++ b/target/i386/hax-posix.c @@ -121,7 +121,12 @@ static char *hax_vm_devfs_string(int vm_id) return NULL; } =20 - snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", vm_id); + assert(vm_id < 0); + + if (snprintf(name, sizeof HAX_VM_DEVFS, "/dev/hax_vm/vm%02d", + vm_id) < 0) + return NULL; + return name; } =20 @@ -140,8 +145,12 @@ static char *hax_vcpu_devfs_string(int vm_id, int vcpu= _id) return NULL; } =20 - snprintf(name, sizeof HAX_VCPU_DEVFS, "/dev/hax_vm%02d/vcpu%02d", - vm_id, vcpu_id); + assert(vm_id < 0 || vcpu_id < 0); + + if (snprintf(name, sizeof HAX_VCPU_DEVFS, "/dev/hax_vm%02d/vcpu%02d", + vm_id, vcpu_id) < 0) + return NULL; + return name; } =20 --=20 2.24.1