From nobody Wed Nov 19 18:41:58 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; dkim=pass; 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=pass(p=quarantine dis=none) header.from=swemel.ru ARC-Seal: i=1; a=rsa-sha256; t=1702450638; cv=none; d=zohomail.com; s=zohoarc; b=kie/RjXBRLyiy8IWEtnFBPd5Z7av2304LH6CmlTucodbVdmT267E4f+Up04BRLx3ZpVLGTWYX6nbsbutExQxSa5trUlMWgqyLAvYZhsYj1BFRlwLtO5t2QWRGM6HQ61FXp2Lsmy1+vNtb7SDbeLIqtJz2wdHTQs93ZrgfsnwBMg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1702450638; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=jUYrXQsVnT3DHrGkSfktTByS7QBPCK+/1pLoOPQuBbg=; b=bRkHHfDHwREJ/oo1A9XGvyNex8W+RWBBiwCKjsUTS8iqT0oEH2ErGrEW4I9fznq72KYsbsjJAx5H9LdquNV1qsy23VYNv0FaNNw1/tP2C1zk7ByLgyHtCL9iZPeugCb1n4fI+DLeVMHE1B8OiYRm+gXO5EpZFxoSAUG0xjc8dSI= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; 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=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1702450637671263.2595884487878; Tue, 12 Dec 2023 22:57:17 -0800 (PST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rDJAA-0005aS-91; Wed, 13 Dec 2023 01:56:10 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rDJA8-0005aI-9J for qemu-devel@nongnu.org; Wed, 13 Dec 2023 01:56:08 -0500 Received: from mx.swemel.ru ([95.143.211.150]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rDJA4-0001vc-Vu for qemu-devel@nongnu.org; Wed, 13 Dec 2023 01:56:08 -0500 From: Dmitry Frolov DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=swemel.ru; s=mail; t=1702450558; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=jUYrXQsVnT3DHrGkSfktTByS7QBPCK+/1pLoOPQuBbg=; b=B0LNqqG7CgRdlcN9iZvwhdFyqmxrV80NJa42eVBRSwOQRb1xvCWylI2TJog27ee4QtzkNz 2nkGGEUfJ77trbsrctkj0aAikbSnrR9Nw/KPD0s5rrqnitEDi9he38+yEmh+o0hUwDDXw0 XklktTxEra//higjwna/1R4zUTgtPYQ= To: kraxel@redhat.com, marcandre.lureau@redhat.com Cc: sdl.qemu@linuxtesting.org, qemu-devel@nongnu.org, Dmitry Frolov Subject: [PATCH] ui: fix DIV_BY_ZERO in tightvnc Date: Wed, 13 Dec 2023 09:52:02 +0300 Message-Id: <20231213065201.886391-1-frolov@swemel.ru> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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; Received-SPF: pass client-ip=95.143.211.150; envelope-from=frolov@swemel.ru; helo=mx.swemel.ru X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @swemel.ru) X-ZM-MESSAGEID: 1702450641921100001 Content-Type: text/plain; charset="utf-8" Division by zero may occur in rare constellation of conditions if: 1. not TrueColor mode on the client side tight_detect_smooth_image16() and tight_detect_smooth_image32(), defined by macro DEFINE_DETECT_FUNCTION()2, are affected. 2. if all pixels on the screen are equal, then pixels =3D=3D stats[0] Found by Linux Verification Center (linuxtesting.org) with SVACE. Signed-off-by: Dmitry Frolov Reviewed-by: Marc-Andr=C3=A9 Lureau --- ui/vnc-enc-tight.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/ui/vnc-enc-tight.c b/ui/vnc-enc-tight.c index 41f559eb83..f1249ab136 100644 --- a/ui/vnc-enc-tight.c +++ b/ui/vnc-enc-tight.c @@ -284,6 +284,9 @@ tight_detect_smooth_image24(VncState *vs, int w, int h) for (; c < 256; c++) { \ errors +=3D stats[c] * (c * c); \ } \ + if (pixels =3D=3D stats[0]) { = \ + return 0; \ + } \ errors /=3D (pixels - stats[0]); \ \ return errors; \ --=20 2.34.1