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 1052FC4332F for ; Thu, 20 Jan 2022 07:08:01 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D686E10E799; Thu, 20 Jan 2022 07:08:00 +0000 (UTC) Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by gabe.freedesktop.org (Postfix) with ESMTPS id A102810E796 for ; Thu, 20 Jan 2022 07:07:59 +0000 (UTC) X-UUID: 67f177b04d4f4e9dad3fc6fb74513b7a-20220120 X-UUID: 67f177b04d4f4e9dad3fc6fb74513b7a-20220120 Received: from mtkexhb01.mediatek.inc [(172.21.101.102)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1004976437; Thu, 20 Jan 2022 15:07:54 +0800 Received: from mtkexhb01.mediatek.inc (172.21.101.102) by mtkmbs10n1.mediatek.inc (172.21.101.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.2.792.15; Thu, 20 Jan 2022 15:07:54 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkexhb01.mediatek.inc (172.21.101.102) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 20 Jan 2022 15:07:53 +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 15:07:52 +0800 From: To: Subject: [PATCH v5] dma-buf: system_heap: Add a size check for allocation Date: Thu, 20 Jan 2022 15:08:50 +0800 Message-ID: <20220120070850.95495-1-guangming.cao@mediatek.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: 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, mingyuan.ma@mediatek.com, caoguangming34@gmail.com, michael.j.ruhl@intel.com, yf.wang@mediatek.com, linux-mediatek@lists.infradead.org, libo.kang@mediatek.com, benjamin.gaignard@linaro.org, bo.song@mediatek.com, matthias.bgg@gmail.com, lmark@codeaurora.org, labbott@redhat.com, christian.koenig@amd.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 --- 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..459dc18bc4a2 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 (len >> PAGE_SHIFT > totalram_pages()) + return ERR_PTR(-EINVAL); + buffer = kzalloc(sizeof(*buffer), GFP_KERNEL); if (!buffer) return ERR_PTR(-ENOMEM); -- 2.17.1