6.12-stable review patch. If anyone has any objections, please let me know.
------------------
From: Zhongqiu Han <quic_zhonhan@xxxxxxxxxxx>
[ Upstream commit 5089b3d874e9933d9842e90410d3af1520494757 ]
If platform_get_resource_byname() fails and returns NULL because DT lacks
an 'mmio' property for the MHI endpoint, dereferencing res->start will
cause a NULL pointer access. Add a check to prevent it.
Fixes: 1bf5f25324f7 ("PCI: endpoint: Add PCI Endpoint function driver for MHI bus")
Link: https://lore.kernel.org/r/20241105120735.1240728-1-quic_zhonhan@xxxxxxxxxxx
Signed-off-by: Zhongqiu Han <quic_zhonhan@xxxxxxxxxxx>
[kwilczynski: error message update per the review feedback]
Signed-off-by: Krzysztof Wilczyński <kwilczynski@xxxxxxxxxx>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Niklas Cassel <cassel@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pci/endpoint/functions/pci-epf-mhi.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 7d070b1def116..54286a40bdfbf 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -867,12 +867,18 @@ static int pci_epf_mhi_bind(struct pci_epf *epf)
{
struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
struct pci_epc *epc = epf->epc;
+ struct device *dev = &epf->dev;
struct platform_device *pdev = to_platform_device(epc->dev.parent);
struct resource *res;
int ret;
/* Get MMIO base address from Endpoint controller */
res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mmio");
+ if (!res) {
+ dev_err(dev, "Failed to get \"mmio\" resource\n");
+ return -ENODEV;
+ }
+
epf_mhi->mmio_phys = res->start;
epf_mhi->mmio_size = resource_size(res);
--
2.43.0
