From patchwork Thu Sep 30 05:43:43 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gibson X-Patchwork-Id: 1534629 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: bilbo.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; secure) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.a=rsa-sha256 header.s=201602 header.b=ESXm3H0L; dkim-atps=neutral Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by bilbo.ozlabs.org (Postfix) with ESMTPS id 4HKj0V0Sprz9sP7 for ; Thu, 30 Sep 2021 15:46:16 +1000 (AEST) Received: from localhost ([::1]:46780 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mVotY-0000uF-Rh for incoming@patchwork.ozlabs.org; Thu, 30 Sep 2021 01:46:12 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:47168) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mVos1-0000tL-Q8; Thu, 30 Sep 2021 01:44:37 -0400 Received: from gandalf.ozlabs.org ([150.107.74.76]:54527) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mVorz-0003LF-Pu; Thu, 30 Sep 2021 01:44:37 -0400 Received: by gandalf.ozlabs.org (Postfix, from userid 1007) id 4HKhyQ6ry5z4xbP; Thu, 30 Sep 2021 15:44:30 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gibson.dropbear.id.au; s=201602; t=1632980670; bh=Hbf5PQQ1MXRc3VxbMWK0lcX0RKfAFcYUPhqyVBTMK/E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ESXm3H0LJw20q73ISEGdt3K4l0pGQYUImjnkmCSDdNCKjLxkV8xZSTCWh1loNgMeJ +XwPLz8B4ymq1Bvmsdy2pLzcrSv+qhFhzAAq2TmNw8O+B9CUS+2Vav4B90+nouAkzF 3g56WJfIMkPZPScEGBq8Dna1MvAf/SelFax2KQ3Q= From: David Gibson To: peter.maydell@linaro.org Subject: [PULL 01/44] host-utils: Fix overflow detection in divu128() Date: Thu, 30 Sep 2021 15:43:43 +1000 Message-Id: <20210930054426.357344-2-david@gibson.dropbear.id.au> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210930054426.357344-1-david@gibson.dropbear.id.au> References: <20210930054426.357344-1-david@gibson.dropbear.id.au> MIME-Version: 1.0 Received-SPF: pass client-ip=150.107.74.76; envelope-from=dgibson@gandalf.ozlabs.org; helo=gandalf.ozlabs.org X-Spam_score_int: -17 X-Spam_score: -1.8 X-Spam_bar: - X-Spam_report: (-1.8 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action 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: Richard Henderson , mark.cave-ayland@ilande.co.uk, qemu-devel@nongnu.org, groug@kaod.org, Luis Pires , hpoussin@reactos.org, clg@kaod.org, qemu-ppc@nongnu.org, philmd@redhat.com, David Gibson Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Luis Pires The previous code didn't detect overflows if the high 64-bit of the dividend were equal to the 64-bit divisor. In that case, 64 bits wouldn't be enough to hold the quotient. Signed-off-by: Luis Pires Reviewed-by: Richard Henderson Message-Id: <20210910112624.72748-2-luis.pires@eldorado.org.br> Signed-off-by: David Gibson --- util/host-utils.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/util/host-utils.c b/util/host-utils.c index 7b9322071d..a789a11b46 100644 --- a/util/host-utils.c +++ b/util/host-utils.c @@ -102,7 +102,7 @@ int divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor) *plow = dlo / divisor; *phigh = dlo % divisor; return 0; - } else if (dhi > divisor) { + } else if (dhi >= divisor) { return 1; } else {