From patchwork Wed Apr 3 09:20:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Yannick FERTRE X-Patchwork-Id: 10883105 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C5EAD139A for ; Wed, 3 Apr 2019 09:20:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B0CCC28928 for ; Wed, 3 Apr 2019 09:20:42 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A45502892B; Wed, 3 Apr 2019 09:20:42 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 5826D28928 for ; Wed, 3 Apr 2019 09:20:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To :From:Reply-To:Cc:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=4iC6WX6BFh+njQA3vM0JLNM98SZTOHlQM1HPIRZiXIA=; b=M2RFidvGabgOZg r0/YWsEd9u+F/hzQwnmQF7B+yJcWU0TJE+iMXhZ68dGnq3Xkbi7JI3be9Dy1mWzoO7DKbFzX5CY7I EYYWzNG7UQWFnv6jiG9rqMuR99rkF4quLx40fM/JvNaTCz6kHiuw+RvqvZ9v8xWgFuIRQVC7zapk1 mUcQAnMiM4tkEdgTMKG4k02Ti56H1SXDAYFeaD5upRS7TPCfWUcDFpdNGz0sNfYgORVMXyPGnx2gB r5hzRObgQ84p5AYJzw+SJ/EgJhCZz2bDUIMR4cO5MOC+2qOFTpH/6K29pbbVeWuAIrgFy6x5K+Mg/ zViHlVjEYX7UHqyTaq2w==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hBc4W-0006gU-Td; Wed, 03 Apr 2019 09:20:40 +0000 Received: from mx08-00178001.pphosted.com ([91.207.212.93] helo=mx07-00178001.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hBc4S-0006g7-P3 for linux-arm-kernel@lists.infradead.org; Wed, 03 Apr 2019 09:20:38 +0000 Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx08-00178001.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x3397F3d015828; Wed, 3 Apr 2019 11:20:30 +0200 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx08-00178001.pphosted.com with ESMTP id 2rmhar2tes-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 03 Apr 2019 11:20:30 +0200 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 0801931; Wed, 3 Apr 2019 09:20:30 +0000 (GMT) Received: from Webmail-eu.st.com (Safex1hubcas22.st.com [10.75.90.92]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id DBC641863; Wed, 3 Apr 2019 09:20:29 +0000 (GMT) Received: from SAFEX1HUBCAS23.st.com (10.75.90.47) by Safex1hubcas22.st.com (10.75.90.92) with Microsoft SMTP Server (TLS) id 14.3.361.1; Wed, 3 Apr 2019 11:20:29 +0200 Received: from localhost (10.201.23.97) by webmail-ga.st.com (10.75.90.48) with Microsoft SMTP Server (TLS) id 14.3.435.0; Wed, 3 Apr 2019 11:20:29 +0200 From: =?utf-8?q?Yannick_Fertr=C3=A9?= To: Yannick Fertre , Philippe Cornu , Benjamin Gaignard , Vincent Abriou , David Airlie , Daniel Vetter , Maxime Coquelin , Alexandre Torgue , , , , Subject: [PATCH] drm/stm: ltdc: limit number of layer to avoid memory overflow Date: Wed, 3 Apr 2019 11:20:16 +0200 Message-ID: <1554283216-2700-1-git-send-email-yannick.fertre@st.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-Originating-IP: [10.201.23.97] X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-04-03_05:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190403_022037_097570_EDE0BF31 X-CRM114-Status: UNSURE ( 9.79 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP If the number of layer is greater than LTDC_MAX_LAYER, we can have memory overflow when reading plane_fpsi[]. Signed-off-by: Yannick Fertré Acked-by: Philippe Cornu --- drivers/gpu/drm/stm/ltdc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 32fd6a3..05bd4b6 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -1021,10 +1021,13 @@ static int ltdc_get_caps(struct drm_device *ddev) struct ltdc_device *ldev = ddev->dev_private; u32 bus_width_log2, lcr, gc2r; - /* at least 1 layer must be managed */ + /* + * at least 1 layer must be managed & the number of layers + * must not exceed LTDC_MAX_LAYER + */ lcr = reg_read(ldev->regs, LTDC_LCR); - ldev->caps.nb_layers = max_t(int, lcr, 1); + ldev->caps.nb_layers = clamp((int)lcr, 1, LTDC_MAX_LAYER); /* set data bus width */ gc2r = reg_read(ldev->regs, LTDC_GC2R);