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

Greg Kroah-Hartman
2020-12-28T16:04:14Z

From: Colin Ian King <colin.king@canonical.com>

[ 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@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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