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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 498ABC433F5 for ; Thu, 13 Jan 2022 12:54:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=65LGSiSosTIAwiGSModP7lNjJm3R4Pa8YaR9799BbV8=; b=pLRkw9UxceQkvw OhDu8QXB79Gik08QD9M4D7VxmMAY1WGRCPoprYHWFfbz6YI+fXIxbbsfXvXYcqwKJs3txHEwgsHQc DvYagclt62337FPq3RTRlpovYgBbU6Eiq1XzGejFWggRr7qluIT0IY7Tbar5/BzU/mewp28N0qBe7 HNICwrpWsoSbE7nJ8TCw9BuH/2ERLqM72nvAuefoiQuUSAR/9tHctN86StxzHL3grBcxAsvqKnnVJ WbUtri3NhyHG1fTtnoA+tR3W6svz/AmX2d7LMtX25PSiB2ZanRDbxwpAqZ5T3+/k8QIptBc6hTYMv 8/TBkTI6K/4QYAcm3Gbg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7zcM-005x3k-NU; Thu, 13 Jan 2022 12:54:14 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1n7zRv-005t7G-QS; Thu, 13 Jan 2022 12:43:30 +0000 X-UUID: ea62b4b834ec40cbafa6ae23b6c4fe36-20220113 X-UUID: ea62b4b834ec40cbafa6ae23b6c4fe36-20220113 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1973514974; Thu, 13 Jan 2022 05:43:21 -0700 Received: from mtkmbs10n2.mediatek.inc (172.21.101.183) by MTKMBS62N2.mediatek.inc (172.29.193.42) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Thu, 13 Jan 2022 04:33:19 -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: CC: , , , , , , , , , , , , , , , , , , , , Guangming 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 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220113_044327_899106_1D893349 X-CRM114-Status: GOOD ( 12.31 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org 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 _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek