From 794a8604fe6e4a311373cde57a86ad4aab9d32b8 Mon Sep 17 00:00:00 2001 From: Niklas Cassel Date: Mon, 3 Apr 2017 17:35:12 -0500 Subject: [PATCH] PCI: dwc: Fix dw_pcie_ops NULL pointer dereference Fix a crash from dereferencing a NULL dw_pcie_ops pointer. For example, on ARTPEC-6: Unable to handle kernel NULL pointer dereference at virtual address 00000004 pgd = c0204000 [00000004] *pgd=00000000 Internal error: Oops: 5 [#1] SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc3-next-20170321 #1 Hardware name: Axis ARTPEC-6 Platform task: db098000 task.stack: db096000 PC is at dw_pcie_writel_dbi+0x2c/0xd0 Prior to 442ec4c04d12 ("PCI: dwc: all: Split struct pcie_port into host-only and core structures"), every driver had a struct pcie_host_ops with function pointers, typically used as: if (pp->ops->readl_rc) return pp->ops->readl_rc(...); 442ec4c04d12 split struct pcie_host_ops into two pieces: struct dw_pcie_host_ops and struct dw_pcie_ops, so the above became: if (pci->ops->readl_dbi) return pci->ops->readl_dbi(...); But pcie-artpec6.c and pcie-designware-plat.c don't need the dw_pcie_ops pointers and didn't supply a pci->ops struct, which leads to NULL pointer dereferences. Supply an empty struct dw_pcie_ops to avoid the NULL pointer dereferences. [bhelgaas: changelog] Fixes: 442ec4c04d12 ("PCI: dwc: all: Split struct pcie_port into host-only and core structures") Signed-off-by: Niklas Cassel Signed-off-by: Bjorn Helgaas Acked-by: Kishon Vijay Abraham I Acked-by: Joao Pinto --- drivers/pci/dwc/pcie-artpec6.c | 4 ++++ drivers/pci/dwc/pcie-designware-plat.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/drivers/pci/dwc/pcie-artpec6.c b/drivers/pci/dwc/pcie-artpec6.c index fcd3ef845883..6d23683c0892 100644 --- a/drivers/pci/dwc/pcie-artpec6.c +++ b/drivers/pci/dwc/pcie-artpec6.c @@ -234,6 +234,9 @@ static int artpec6_add_pcie_port(struct artpec6_pcie *artpec6_pcie, return 0; } +static const struct dw_pcie_ops dw_pcie_ops = { +}; + static int artpec6_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -252,6 +255,7 @@ static int artpec6_pcie_probe(struct platform_device *pdev) return -ENOMEM; pci->dev = dev; + pci->ops = &dw_pcie_ops; artpec6_pcie->pci = pci; diff --git a/drivers/pci/dwc/pcie-designware-plat.c b/drivers/pci/dwc/pcie-designware-plat.c index b6c832ba39dd..f20d494922ab 100644 --- a/drivers/pci/dwc/pcie-designware-plat.c +++ b/drivers/pci/dwc/pcie-designware-plat.c @@ -86,6 +86,9 @@ static int dw_plat_add_pcie_port(struct pcie_port *pp, return 0; } +static const struct dw_pcie_ops dw_pcie_ops = { +}; + static int dw_plat_pcie_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; @@ -103,6 +106,7 @@ static int dw_plat_pcie_probe(struct platform_device *pdev) return -ENOMEM; pci->dev = dev; + pci->ops = &dw_pcie_ops; dw_plat_pcie->pci = pci; -- 2.34.1