[PATCH 08/11] pci: Check region ranges are addressable

[Andrew Scull]

When parsing the `ranges` DT node, check that both extremes of the
regions are addressable without overflow. This assumption can then be
safely made when processing the regions.

Signed-off-by: Andrew Scull <ascull at google.com>
---
 drivers/pci/pci-uclass.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
index 33dda00002..54a05d7567 100644
--- a/drivers/pci/pci-uclass.c
+++ b/drivers/pci/pci-uclass.c
@@ -1013,7 +1013,22 @@ static void decode_regions(struct pci_controller *hose, ofnode parent_node,
 
 		if (!IS_ENABLED(CONFIG_SYS_PCI_64BIT) &&
 		    type == PCI_REGION_MEM && upper_32_bits(pci_addr)) {
-			debug(" - beyond the 32-bit boundary, ignoring\n");
+			debug(" - pci_addr beyond the 32-bit boundary, ignoring\n");
+			continue;
+		}
+
+		if (!IS_ENABLED(CONFIG_PHYS_64BIT) && upper_32_bits(addr)) {
+			debug(" - addr beyond the 32-bit boundary, ignoring\n");
+			continue;
+		}
+
+		if (~((pci_addr_t)0) - pci_addr < size) {
+			debug(" - PCI range exceeds max address, ignoring\n");
+			continue;
+		}
+
+		if (~((phys_addr_t)0) - addr < size) {
+			debug(" - phys range exceeds max address, ignoring\n");
 			continue;
 		}
 
-- 
2.35.1.894.gb6a874cedc-goog