[PATCH 4.19 181/346] PCI: Fix overflow in command-line resource alignment requests

[Greg Kroah-Hartman]

From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

[ Upstream commit cc73eb321d246776e5a9f7723d15708809aa3699 ]

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@xxxxxxxxxxxxx>
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reviewed-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/pci/pci.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 5103d4b140ee3..cd628dd73719b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -5854,7 +5854,7 @@ 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",
-- 
2.27.0