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 CEB60C433EF for ; Thu, 20 Jan 2022 09:59:48 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3E0DF10E285; Thu, 20 Jan 2022 09:59:48 +0000 (UTC) Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by gabe.freedesktop.org (Postfix) with ESMTPS id A6CA310E243 for ; Thu, 20 Jan 2022 09:59:46 +0000 (UTC) X-UUID: fd05882b4df84d1e9a1d3b7ebbe5731f-20220120 X-UUID: fd05882b4df84d1e9a1d3b7ebbe5731f-20220120 Received: from mtkcas11.mediatek.inc [(172.21.101.40)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1198683157; Thu, 20 Jan 2022 17:59:40 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.3; Thu, 20 Jan 2022 17:59:38 +0800 Received: from mszswglt01.gcn.mediatek.inc (10.16.20.20) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Thu, 20 Jan 2022 17:59:37 +0800 From: To: Subject: [PATCH v6 RESEND] dma-buf: system_heap: Add a size check for allocation Date: Thu, 20 Jan 2022 18:00:36 +0800 Message-ID: <20220120100036.99867-1-guangming.cao@mediatek.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220120085259.98147-1-guangming.cao@mediatek.com> References: <20220120085259.98147-1-guangming.cao@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N 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: , Cc: linux-arm-kernel@lists.infradead.org, linaro-mm-sig@lists.linaro.org, Guangming , wsd_upstream@mediatek.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, caoguangming34@gmail.com, michael.j.ruhl@intel.com, yf.wang@mediatek.com, libo.kang@mediatek.com, benjamin.gaignard@linaro.org, bo.song@mediatek.com, matthias.bgg@gmail.com, linux-mediatek@lists.infradead.org, lmark@codeaurora.org, labbott@redhat.com, mingyuan.ma@mediatek.com, jianjiao.zeng@mediatek.com, linux-media@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Guangming Add a size check for allocation since the allocation size should be always less than the total DRAM size on system heap. Adding this check can prevent comsuming too much time for invalid allocations. Signed-off-by: Guangming Acked-by: John Stultz --- drivers/dma-buf/heaps/system_heap.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/drivers/dma-buf/heaps/system_heap.c b/drivers/dma-buf/heaps/system_heap.c index 23a7e74ef966..b65e597a742f 100644 --- a/drivers/dma-buf/heaps/system_heap.c +++ b/drivers/dma-buf/heaps/system_heap.c @@ -347,6 +347,14 @@ static struct dma_buf *system_heap_allocate(struct dma_heap *heap, struct page *page, *tmp_page; int i, ret = -ENOMEM; + /* + * Size check. The "len" should be less than totalram since system_heap + * memory is comes from system. Adding check here can prevent comsuming + * too much time for invalid allocations. + */ + if (PFN_DOWN(len) > totalram_pages()) + return ERR_PTR(-EINVAL); + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); if (!buffer) return ERR_PTR(-ENOMEM); -- 2.17.1