PCI: Fix overflow in command-line resource alignment requests

The shift of 1 by align_order is evaluated using 32 bit arithmetic and the
result is assigned to a resource_size_t type variable that is a 64 bit
unsigned integer on 64 bit platforms. Fix an overflow before widening issue
by making the 1 a ULL.

Addresses-Coverity: ("Unintentional integer overflow")
Fixes: 32a9a682bef2 ("PCI: allow assignment of memory resources with a specified alignment")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7112687763715637fcbd538c4018c20d134279e0..dd4bbb699abdc613e9c256afa4d9ed2bb5d491ee 100644 (file)
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -6216,7 +6216,7 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
                ret = pci_dev_str_match(dev, p, &p);
                if (ret == 1) {
                        *resize = true;
-                       align = 1 << align_order;
+                       align = 1ULL << align_order;
                        break;
                } else if (ret < 0) {
                        pr_err("PCI: Can't parse resource_alignment parameter: %s\n",