diff mbox series

[v3] ACPI: PCI: check if the root io space is page aligned

Message ID 20240814-check_pci_probe_res-v3-1-b6eaa6f99032@gmail.com
State Superseded
Headers show
Series [v3] ACPI: PCI: check if the root io space is page aligned | expand

Commit Message

Miao Wang via B4 Relay Aug. 14, 2024, 12:09 p.m. UTC 
From: Miao Wang <shankerwangmiao@gmail.com>

When the IO resource given by _CRS method is not page aligned, especially
when the page size is larger than 4KB, serious problems will happen
because the misaligned address is passed down to pci_remap_iospace(),
then to vmap_page_range(), and finally to vmap_pte_range(), where the
length between addr and end is expected to be divisible by PAGE_SIZE, or
the loop will overrun till the pfn_none check fails.

Signed-off-by: Miao Wang <shankerwangmiao@gmail.com>
---
Changes in v3:
- Adjust code formatting.
- Reword the commit message for further description of the possible reason
  leading to misaligned IO resource addresses.
- Link to v2: https://lore.kernel.org/r/20240814-check_pci_probe_res-v2-1-a03c8c9b498b@gmail.com

Changes in v2:
- Sorry for posting out the draft version in V1, fixed a silly compiling issue.
- Link to v1: https://lore.kernel.org/r/20240814-check_pci_probe_res-v1-1-122ee07821ab@gmail.com
---
 drivers/acpi/pci_root.c | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)


---
base-commit: 7c626ce4bae1ac14f60076d00eafe71af30450ba
change-id: 20240813-check_pci_probe_res-27e3e6df72b2

Best regards,
diff mbox series

Patch

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index d0bfb3706801..a425e93024f2 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -858,7 +858,7 @@  static void acpi_pci_root_validate_resources(struct device *dev,
 	}
 }
 
-static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
+static void acpi_pci_root_remap_iospace(struct acpi_device *device,
 			struct resource_entry *entry)
 {
 #ifdef PCI_IOBASE
@@ -868,7 +868,15 @@  static void acpi_pci_root_remap_iospace(struct fwnode_handle *fwnode,
 	resource_size_t length = resource_size(res);
 	unsigned long port;
 
-	if (pci_register_io_range(fwnode, cpu_addr, length))
+	if (!PAGE_ALIGNED(cpu_addr) || !PAGE_ALIGNED(length) ||
+	    !PAGE_ALIGNED(pci_addr)) {
+		dev_err(&device->dev,
+			FW_BUG "I/O resource %pR or its offset %pa is not page aligned\n",
+			res, &entry->offset);
+		goto err;
+	}
+
+	if (pci_register_io_range(&device->fwnode, cpu_addr, length))
 		goto err;
 
 	port = pci_address_to_pio(cpu_addr);
@@ -910,7 +918,7 @@  int acpi_pci_probe_root_resources(struct acpi_pci_root_info *info)
 	else {
 		resource_list_for_each_entry_safe(entry, tmp, list) {
 			if (entry->res->flags & IORESOURCE_IO)
-				acpi_pci_root_remap_iospace(&device->fwnode,
+				acpi_pci_root_remap_iospace(device,
 						entry);
 
 			if (entry->res->flags & IORESOURCE_DISABLED)