From 0297dce758a021ccf2c0f4e164d5403ef722961c Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Tue, 9 Dec 2025 14:37:56 -0800 Subject: [PATCH] PCI: cadence: Avoid signed 64-bit truncation and invalid sort The cdns_pcie_host_dma_ranges_cmp() element comparison function used by list_sort() is of type list_cmp_func_t, so it returns a 32-bit int. cdns_pcie_host_dma_ranges_cmp() computes a resource_size_t difference that may be a 64-bit value, and truncating that difference to a 32-bit return value may change the sign and result in an invalid sort order. Avoid the truncation and invalid sort order by returning -1, 0, or 1. Signed-off-by: Ian Rogers Signed-off-by: Manivannan Sadhasivam [bhelgaas: commit log] Signed-off-by: Bjorn Helgaas Link: https://patch.msgid.link/20251209223756.2321578-1-irogers@google.com --- .../controller/cadence/pcie-cadence-host-common.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/pci/controller/cadence/pcie-cadence-host-common.c b/drivers/pci/controller/cadence/pcie-cadence-host-common.c index 15415d7f35ee9..2b0211870f02a 100644 --- a/drivers/pci/controller/cadence/pcie-cadence-host-common.c +++ b/drivers/pci/controller/cadence/pcie-cadence-host-common.c @@ -173,11 +173,21 @@ int cdns_pcie_host_dma_ranges_cmp(void *priv, const struct list_head *a, const struct list_head *b) { struct resource_entry *entry1, *entry2; + u64 size1, size2; entry1 = container_of(a, struct resource_entry, node); entry2 = container_of(b, struct resource_entry, node); - return resource_size(entry2->res) - resource_size(entry1->res); + size1 = resource_size(entry1->res); + size2 = resource_size(entry2->res); + + if (size1 > size2) + return -1; + + if (size1 < size2) + return 1; + + return 0; } EXPORT_SYMBOL_GPL(cdns_pcie_host_dma_ranges_cmp); -- 2.47.3