From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1507DC433E2 for ; Tue, 1 Sep 2020 14:13:13 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id C1A14207D3 for ; Tue, 1 Sep 2020 14:13:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="CgCKSGEL" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C1A14207D3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:43696 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kD727-0002z3-TC for qemu-devel@archiver.kernel.org; Tue, 01 Sep 2020 10:13:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:55066) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kD6zF-0005C1-Cs for qemu-devel@nongnu.org; Tue, 01 Sep 2020 10:10:13 -0400 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:28257 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kD6zC-0003kK-7q for qemu-devel@nongnu.org; Tue, 01 Sep 2020 10:10:12 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1598969408; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=cNgVF9HWZy4RUr6DCucDvzASAeqTHl0TqesZxD7F8xs=; b=CgCKSGELaQASl2+mkUN3aHNiCDCq8j7bBiCEZibykwbNS8WEWnLP3nl+WJWU1ZoHtTcCTs 6nVrz1vUxs0Ms4oblHVKgo97LPjlwpOIy90hFxeJjbTOyCLhlKn+HB4L2Psw0vBYg8Hpe8 sxPKqbpf4+g3k0DtAGgAab8ACai9SGs= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-376-7XrF3pF1M8K0diA-ZOYiuA-1; Tue, 01 Sep 2020 10:09:53 -0400 X-MC-Unique: 7XrF3pF1M8K0diA-ZOYiuA-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3201818CBC41; Tue, 1 Sep 2020 14:09:52 +0000 (UTC) Received: from sirius.home.kraxel.org (ovpn-112-54.ams2.redhat.com [10.36.112.54]) by smtp.corp.redhat.com (Postfix) with ESMTP id 04E2A7C584; Tue, 1 Sep 2020 14:09:46 +0000 (UTC) Received: by sirius.home.kraxel.org (Postfix, from userid 1000) id C0D7D17447; Tue, 1 Sep 2020 16:09:44 +0200 (CEST) From: Gerd Hoffmann To: qemu-devel@nongnu.org Subject: [PATCH v2] cirrus: handle wraparound in cirrus_invalidate_region Date: Tue, 1 Sep 2020 16:09:44 +0200 Message-Id: <20200901140944.24101-1-kraxel@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=kraxel@redhat.com X-Mimecast-Spam-Score: 0.002 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=205.139.110.120; envelope-from=kraxel@redhat.com; helo=us-smtp-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/09/01 05:11:36 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] 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, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , Li Qiang , Gerd Hoffmann Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Code simply asserts that there is no wraparound instead of handling it properly. The assert() can be triggered by the guest (must be privilidged inside the guest though). Fix it. Buglink: https://bugs.launchpad.net/qemu/+bug/1880189 Cc: Li Qiang Reported-by: Philippe Mathieu-Daudé Signed-off-by: Gerd Hoffmann Reviewed-by: Philippe Mathieu-Daudé --- hw/display/cirrus_vga.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/hw/display/cirrus_vga.c b/hw/display/cirrus_vga.c index 212d6f5e6145..5d1f62e50e67 100644 --- a/hw/display/cirrus_vga.c +++ b/hw/display/cirrus_vga.c @@ -640,10 +640,16 @@ static void cirrus_invalidate_region(CirrusVGAState * s, int off_begin, } for (y = 0; y < lines; y++) { - off_cur = off_begin; + off_cur = off_begin & s->cirrus_addr_mask; off_cur_end = ((off_cur + bytesperline - 1) & s->cirrus_addr_mask) + 1; - assert(off_cur_end >= off_cur); - memory_region_set_dirty(&s->vga.vram, off_cur, off_cur_end - off_cur); + if (off_cur_end >= off_cur) { + memory_region_set_dirty(&s->vga.vram, off_cur, off_cur_end - off_cur); + } else { + /* wraparound */ + memory_region_set_dirty(&s->vga.vram, off_cur, + s->cirrus_addr_mask + 1 - off_cur); + memory_region_set_dirty(&s->vga.vram, 0, off_cur_end); + } off_begin += off_pitch; } } -- 2.27.0