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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id ADBFCCD4F54 for ; Tue, 19 May 2026 20:23:53 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1476810E31E; Tue, 19 May 2026 20:23:53 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=berkoc.com header.i=@berkoc.com header.b="pt/i+7jB"; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=berkoc.com header.i=@berkoc.com header.b="NtyDyKZ2"; dkim-atps=neutral Received: from mail-03.1984.is (mail-03.1984.is [93.95.224.70]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0164710E31E for ; Tue, 19 May 2026 20:23:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=berkoc.com; s=1984; h=Cc:To:Subject:Date:From:References:In-Reply-To:Message-ID:Sender: Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=Q+vEsl1LzqgZ9PXOM4pI7809um9+xqvACDkfc8DXhAs=; b=pt/i+7jB4o4acCY+GOX62c5oFO Olj3Wq65lCWKBvLt5SiwlfTbi+gcNf2g935qFdnvBL6mgW31y4EqZxLYDGy5muSNx/AGr+B0Etlns Xhs/zpxgF79USKMJIetXMdDv8xooyeNx6bFnW2VBC2iN4Hq8u5fEdBugopXWaS/vrXRwjC7QvMvSb l5dYFJSJ/6o3G/awid7vWs38W12N+tQug7ek4EXmh5A+Qo0LqFF9tLvR9T77EZL689JQTwK6QiZWC jfbhJkNlgeuedF8U93tKyFC85jyH5loeJTwkZQJtuQL1Zi1Dl8PF7hKx3h+3ZK+dADT2KLuUj3ogz Zfzsdw8w==; Received: from localhost by mail-03.1984.is with utf8esmtp (Exim 4.96) (envelope-from ) id 1wPQyj-007hQI-1k; Tue, 19 May 2026 20:23:50 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=berkoc.com; i=@berkoc.com; q=dns/txt; s=me; t=1779222219; h=message-id : date : subject : cc : to : from : sender : reply-to; bh=Q+vEsl1LzqgZ9PXOM4pI7809um9+xqvACDkfc8DXhAs=; b=NtyDyKZ2kLyQW22Raj9sviRBlW1//LR1ZvsiDciW7rfm0O0fb9tWJbFGgWq+jGDeXOjdh /hJCXSCl7EaEcEma+cXiJT1v7jdojexcVCX7K6XwacOW14ZdlpbyoxAYxnodB4HfozrmuJe osN7rf9ilwSflKZKFqdKaHSEaSIJ1VQlBHdx0aP5xSUkBzlFYSztA2JibpkebMa4zOIIvJg XfuT3zyazBL00qouvZdWLYkXLw193SSOvMeAEbrBdEETYVsohMUKykPJHvG7gf5mOyAu3PU Fl2m5jXH5pRUIyssrDDHnY08F9RmhmKSEktWY+o6oqQ+E27WPVou7Y+PYzmA== Message-ID: <1b88bc7edeb2f0153475225b67f19aaca629eca8.1779221799.git.me@berkoc.com> In-Reply-To: References: From: Berkant Koc Date: Tue, 19 May 2026 22:08:17 +0200 Subject: [PATCH v3 1/2] drm/hyperv: validate resolution_count and fix WIN8 fallback To: Saurabh Sengar , Dexuan Cui , Long Li Cc: linux-hyperv@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, K. Y. Srinivasan , Haiyang Zhang , Wei Liu , Michael Kelley , Thomas Zimmermann , Maarten Lankhorst , Maxime Ripard , Deepak Rawat X-Authenticated-User: me@berkoc.com X-Sender-Address: me@berkoc.com X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" A SYNTHVID_RESOLUTION_RESPONSE with resolution_count > 64 walks past the supported_resolution[SYNTHVID_MAX_RESOLUTION_COUNT] array in the parse loop. Bound resolution_count against the array size, folded into the existing zero-check. When the WIN10 resolution probe fails, the caller in hyperv_connect_vsp() left hv->screen_*_max / preferred_* unpopulated, which sets mode_config.max_width / max_height to 0 and makes drm_internal_framebuffer_create() reject every userspace framebuffer with -EINVAL. The pre-WIN10 branch had the same gap for preferred_width / preferred_height. Use a single post-probe fallback guarded by screen_width_max == 0 so both paths converge on the WIN8 defaults. Signed-off-by: Berkant Koc Assisted-by: Claude:claude-opus-4-7 berkoc-pipeline Fixes: 76c56a5affeb ("drm/hyperv: Add DRM driver for hyperv synthetic video device") Cc: stable@vger.kernel.org # 5.14+ --- drivers/gpu/drm/hyperv/hyperv_drm_proto.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c index 051ecc526..c3d0ff229 100644 --- a/drivers/gpu/drm/hyperv/hyperv_drm_proto.c +++ b/drivers/gpu/drm/hyperv/hyperv_drm_proto.c @@ -391,8 +391,11 @@ static int hyperv_get_supported_resolution(struct hv_device *hdev) return -ETIMEDOUT; } - if (msg->resolution_resp.resolution_count == 0) { - drm_err(dev, "No supported resolutions\n"); + if (msg->resolution_resp.resolution_count == 0 || + msg->resolution_resp.resolution_count > + SYNTHVID_MAX_RESOLUTION_COUNT) { + drm_err(dev, "Invalid resolution count: %d\n", + msg->resolution_resp.resolution_count); return -ENODEV; } @@ -508,9 +511,13 @@ int hyperv_connect_vsp(struct hv_device *hdev) ret = hyperv_get_supported_resolution(hdev); if (ret) drm_err(dev, "Failed to get supported resolution from host, use default\n"); - } else { + } + + if (!hv->screen_width_max) { hv->screen_width_max = SYNTHVID_WIDTH_WIN8; hv->screen_height_max = SYNTHVID_HEIGHT_WIN8; + hv->preferred_width = SYNTHVID_WIDTH_WIN8; + hv->preferred_height = SYNTHVID_HEIGHT_WIN8; } hv->mmio_megabytes = hdev->channel->offermsg.offer.mmio_megabytes; -- 2.47.3