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 B73AFC433F5 for ; Thu, 13 Jan 2022 12:33:29 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5499510E934; Thu, 13 Jan 2022 12:33:28 +0000 (UTC) Received: from mailgw02.mediatek.com (unknown [210.61.82.184]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0340810E934 for ; Thu, 13 Jan 2022 12:33:26 +0000 (UTC) X-UUID: a357bcd85de4422e9e90e55554a8dd4d-20220113 X-UUID: a357bcd85de4422e9e90e55554a8dd4d-20220113 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 1167861225; Thu, 13 Jan 2022 20:33:19 +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, 13 Jan 2022 20:33:17 +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, 13 Jan 2022 20:33:16 +0800 From: To: Subject: [PATCH v3] dma-buf: dma-heap: Add a size check for allocation Date: Thu, 13 Jan 2022 20:34:06 +0800 Message-ID: <20220113123406.11520-1-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, mingyuan.ma@mediatek.com, Guangming , wsd_upstream@mediatek.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, 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, 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 is always less than the total DRAM size. Without this check, once the invalid size allocation runs on a process that can't be killed by OOM flow(such as "gralloc" on Android devices), it will cause a kernel exception, and to make matters worse, we can't find who are using so many memory with "dma_buf_debug_show" since the relevant dma-buf hasn't exported. To make OOM issue easier, maybe need dma-buf framework to dump the buffer size under allocating in "dma_buf_debug_show". Signed-off-by: Guangming Signed-off-by: jianjiao zeng --- v3: 1. update patch, use right shift to replace division. 2. update patch, add reason in code and commit message. v2: 1. update size limitation as total_dram page size. 2. update commit message --- drivers/dma-buf/dma-heap.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/dma-buf/dma-heap.c b/drivers/dma-buf/dma-heap.c index 56bf5ad01ad5..1fd382712584 100644 --- a/drivers/dma-buf/dma-heap.c +++ b/drivers/dma-buf/dma-heap.c @@ -55,6 +55,16 @@ static int dma_heap_buffer_alloc(struct dma_heap *heap, size_t len, struct dma_buf *dmabuf; int fd; + /* + * Invalid size check. The "len" should be less than totalram. + * + * Without this check, once the invalid size allocation runs on a process that + * can't be killed by OOM flow(such as "gralloc" on Android devices), it will + * cause a kernel exception, and to make matters worse, we can't find who are using + * so many memory with "dma_buf_debug_show" since the relevant dma-buf hasn't exported. + */ + if (len >> PAGE_SHIFT > totalram_pages()) + return -EINVAL; /* * Allocations from all heaps have to begin * and end on page boundaries. -- 2.17.1