[PATCH v4 5/5] PCI: endpoint: Verify that requested BAR size is a power of two

[Niklas Cassel <cassel@kernel.org>]

When allocating a BAR using pci_epf_alloc_space(), there are checks that
round up the size to a power of two.

However, there is no check in pci_epc_set_bar() which verifies that the
requested BAR size is a power of two.

Add a power of two check in pci_epc_set_bar(), so that we don't need to
add such a check in each and every PCI endpoint controller driver.

Signed-off-by: Niklas Cassel <cassel@kernel.org>
---
 drivers/pci/endpoint/pci-epc-core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/endpoint/pci-epc-core.c b/drivers/pci/endpoint/pci-epc-core.c
index c69c133701c9..6062677e9ffe 100644
--- a/drivers/pci/endpoint/pci-epc-core.c
+++ b/drivers/pci/endpoint/pci-epc-core.c
@@ -622,6 +622,9 @@ int pci_epc_set_bar(struct pci_epc *epc, u8 func_no, u8 vfunc_no,
 	    (epc_features->bar[bar].fixed_size != epf_bar->size))
 		return -EINVAL;
 
+	if (!is_power_of_2(epf_bar->size))
+		return -EINVAL;
+
 	if ((epf_bar->barno == BAR_5 && flags & PCI_BASE_ADDRESS_MEM_TYPE_64) ||
 	    (flags & PCI_BASE_ADDRESS_SPACE_IO &&
 	     flags & PCI_BASE_ADDRESS_IO_MASK) ||
-- 
2.47.0