From: Pali Rohár <pali@kernel.org>
Date: Thu, 25 Nov 2021 12:45:51 +0000 (+0100)
Subject: PCI: mvebu: Check for valid ports
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=8cdabfdd5a22ded53ab18f50df48e04dba744ad4;p=linux.git

PCI: mvebu: Check for valid ports

Some mvebu ports do not have to be initialized. So skip these uninitialized
mvebu ports in every port iteration function to prevent access to unmapped
memory or dereferencing NULL pointers. Uninitialized mvebu port has base
address set to NULL.

Link: https://lore.kernel.org/r/20211125124605.25915-2-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
---

diff --git a/drivers/pci/controller/pci-mvebu.c b/drivers/pci/controller/pci-mvebu.c
index f2180e4630a1b..51cf3ecb4121b 100644
--- a/drivers/pci/controller/pci-mvebu.c
+++ b/drivers/pci/controller/pci-mvebu.c
@@ -606,6 +606,9 @@ static struct mvebu_pcie_port *mvebu_pcie_find_port(struct mvebu_pcie *pcie,
 	for (i = 0; i < pcie->nports; i++) {
 		struct mvebu_pcie_port *port = &pcie->ports[i];
 
+		if (!port->base)
+			continue;
+
 		if (bus->number == 0 && port->devfn == devfn)
 			return port;
 		if (bus->number != 0 &&
@@ -781,6 +784,8 @@ static int mvebu_pcie_suspend(struct device *dev)
 	pcie = dev_get_drvdata(dev);
 	for (i = 0; i < pcie->nports; i++) {
 		struct mvebu_pcie_port *port = pcie->ports + i;
+		if (!port->base)
+			continue;
 		port->saved_pcie_stat = mvebu_readl(port, PCIE_STAT_OFF);
 	}
 
@@ -795,6 +800,8 @@ static int mvebu_pcie_resume(struct device *dev)
 	pcie = dev_get_drvdata(dev);
 	for (i = 0; i < pcie->nports; i++) {
 		struct mvebu_pcie_port *port = pcie->ports + i;
+		if (!port->base)
+			continue;
 		mvebu_writel(port, port->saved_pcie_stat, PCIE_STAT_OFF);
 		mvebu_pcie_setup_hw(port);
 	}