[PATCH] PCI: epf-mhi: Fix potential NULL dereference in pci_epf_mhi_bind()

[Zhongqiu Han]

If platform_get_resource_byname() fails and returns NULL, 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")
Signed-off-by: Zhongqiu Han <quic_zhonhan@xxxxxxxxxxx>
---
 drivers/pci/endpoint/functions/pci-epf-mhi.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
index 7d070b1def11..2712026733ab 100644
--- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
+++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
@@ -873,6 +873,11 @@ static int pci_epf_mhi_bind(struct pci_epf *epf)
 
 	/* Get MMIO base address from Endpoint controller */
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "mmio");
+	if (!res) {
+		dev_err(&pdev->dev, "Failed to get MMIO base address\n");
+		return -ENODEV;
+	}
+
 	epf_mhi->mmio_phys = res->start;
 	epf_mhi->mmio_size = resource_size(res);
 
-- 
2.25.1