Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752389AbdDCJwQ (ORCPT ); Mon, 3 Apr 2017 05:52:16 -0400 Received: from ozlabs.org ([103.22.144.67]:35365 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751431AbdDCJvv (ORCPT ); Mon, 3 Apr 2017 05:51:51 -0400 From: Alistair Popple To: mpe@ellerman.id.au Cc: linuxppc-dev@ozlabs.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, mhairgrove@nvidia.com, robh+dt@kernel.org, shailendras@nvidia.com, Alistair Popple Subject: [PATCH v2 2/3] powerpc/powernv: Add sanity checks to pnv_pci_get_{gpu|npu}_dev Date: Mon, 3 Apr 2017 19:51:43 +1000 Message-Id: <1491213104-24450-2-git-send-email-alistair@popple.id.au> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1491213104-24450-1-git-send-email-alistair@popple.id.au> References: <1491213104-24450-1-git-send-email-alistair@popple.id.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1349 Lines: 43 The pnv_pci_get_{gpu|npu}_dev functions are used to find associations between nvlink PCIe devices and standard PCIe devices. However they lacked basic sanity checking which results in NULL pointer dereferencing if they are incorrect called can be harder to spot than an explicit WARN_ON. Signed-off-by: Alistair Popple --- arch/powerpc/platforms/powernv/npu-dma.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/powerpc/platforms/powernv/npu-dma.c b/arch/powerpc/platforms/powernv/npu-dma.c index 1c383f3..050bd5d 100644 --- a/arch/powerpc/platforms/powernv/npu-dma.c +++ b/arch/powerpc/platforms/powernv/npu-dma.c @@ -37,6 +37,12 @@ struct pci_dev *pnv_pci_get_gpu_dev(struct pci_dev *npdev) struct device_node *dn; struct pci_dev *gpdev; + if (WARN_ON(!npdev)) + return NULL; + + if (WARN_ON(!npdev->dev.of_node)) + return NULL; + /* Get assoicated PCI device */ dn = of_parse_phandle(npdev->dev.of_node, "ibm,gpu", 0); if (!dn) @@ -55,6 +61,12 @@ struct pci_dev *pnv_pci_get_npu_dev(struct pci_dev *gpdev, int index) struct device_node *dn; struct pci_dev *npdev; + if (WARN_ON(!gpdev)) + return NULL; + + if (WARN_ON(!gpdev->dev.of_node)) + return NULL; + /* Get assoicated PCI device */ dn = of_parse_phandle(gpdev->dev.of_node, "ibm,npu", index); if (!dn) -- 2.1.4