From patchwork Wed Jun 3 12:47:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prasad Pandit X-Patchwork-Id: 11585655 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 80D3D618 for ; Wed, 3 Jun 2020 12:50:14 +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 26CEA2067B for ; Wed, 3 Jun 2020 12:50:14 +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="Gkpw0brt" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 26CEA2067B 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+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:55484 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jgSqT-00083s-8y for patchwork-qemu-devel@patchwork.kernel.org; Wed, 03 Jun 2020 08:50:13 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50514) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jgSq3-0007c3-Nq for qemu-devel@nongnu.org; Wed, 03 Jun 2020 08:49:47 -0400 Received: from us-smtp-1.mimecast.com ([207.211.31.81]:26540 helo=us-smtp-delivery-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 1jgSq2-0000YM-T4 for qemu-devel@nongnu.org; Wed, 03 Jun 2020 08:49:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591188585; 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=5EGQLuICNFeRjd9HJONtfAD5ly5gPefyS6jbVQcj0Ao=; b=Gkpw0brt9/NTK8dGpvwMPAQ13HNwALUdFh9oMbksJp0VQIpelN2RXvOQVHD2yxVIuCknMO eNfgrJAn8aApy1J2IkzFqU8fSOc0q89RSdAnHph9uv/HCcaHuGEMYUoaHlW0cMSWlDkZcx NNTY/900Mx5ylhdhp867yZ1e5nG3h+U= 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-109-p9hXp0puPC6A-xQpsBlGQg-1; Wed, 03 Jun 2020 08:49:43 -0400 X-MC-Unique: p9hXp0puPC6A-xQpsBlGQg-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4478E18A8225; Wed, 3 Jun 2020 12:49:42 +0000 (UTC) Received: from localhost.localdomain (unknown [10.74.8.119]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 012A25D9D3; Wed, 3 Jun 2020 12:49:35 +0000 (UTC) From: P J P To: Gerd Hoffmann Subject: [PATCH] ati-vga: increment mm_index in ati_mm_read/write Date: Wed, 3 Jun 2020 18:17:32 +0530 Message-Id: <20200603124732.1137892-1-ppandit@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=207.211.31.81; envelope-from=ppandit@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/03 01:12:11 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_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001 autolearn=_AUTOLEARN 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: Prasad J Pandit , Yi Ren , QEMU Developers , Ren Ding , Hanqing Zhao Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" From: Prasad J Pandit While accessing VGA registers via ati_mm_read/write routines, a guest may set 's->regs.mm_index' such that it leads to infinite recursion. Increment the mm_index value to avoid it. Reported-by: Ren Ding Reported-by: Hanqing Zhao Reported-by: Yi Ren Signed-off-by: Prasad J Pandit --- hw/display/ati.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/hw/display/ati.c b/hw/display/ati.c index 065f197678..fa9061ad0b 100644 --- a/hw/display/ati.c +++ b/hw/display/ati.c @@ -286,7 +286,8 @@ static uint64_t ati_mm_read(void *opaque, hwaddr addr, unsigned int size) val = ldn_le_p(s->vga.vram_ptr + idx, size); } } else { - val = ati_mm_read(s, s->regs.mm_index + addr - MM_DATA, size); + uint32_t idx = s->regs.mm_index++; + val = ati_mm_read(s, idx + addr - MM_DATA, size); } break; case BIOS_0_SCRATCH ... BUS_CNTL - 1: @@ -521,7 +522,8 @@ static void ati_mm_write(void *opaque, hwaddr addr, stn_le_p(s->vga.vram_ptr + idx, size, data); } } else { - ati_mm_write(s, s->regs.mm_index + addr - MM_DATA, data, size); + uint32_t idx = s->regs.mm_index++; + ati_mm_write(s, idx + addr - MM_DATA, data, size); } break; case BIOS_0_SCRATCH ... BUS_CNTL - 1: