6.6-stable review patch. If anyone has any objections, please let me know.
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From: Zhongqiu Han quic_zhonhan@quicinc.com
[ 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@quicinc.com Signed-off-by: Zhongqiu Han quic_zhonhan@quicinc.com [kwilczynski: error message update per the review feedback] Signed-off-by: Krzysztof Wilczyński kwilczynski@kernel.org [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas bhelgaas@google.com Reviewed-by: Niklas Cassel cassel@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- 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 34e7191f95086..87154992ea11b 100644 --- a/drivers/pci/endpoint/functions/pci-epf-mhi.c +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c @@ -600,12 +600,18 @@ 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);