diff mbox series

[1/1] cxl/pci: Check dport->regs.rcd_pcie_cap availability before accessing

Message ID 20241129132825.569237-1-ming.li@zohomail.com
State New
Headers show
Series [1/1] cxl/pci: Check dport->regs.rcd_pcie_cap availability before accessing | expand

Commit Message

Li Ming Nov. 29, 2024, 1:28 p.m. UTC
RCD Upstream Port's PCI Express Capability is a component registers
block stored in RCD Upstream Port RCRB. CXL PCI driver helps to map it
during the RCD probing, but mapping failure is allowed for component
registers blocks in CXL PCI driver.

dport->regs.rcd_pcie_cap is used to store the virtual address of the RCD
Upstream Port's PCI Express Capability, add a dport->regs.rcd_pcie_cap
checking in rcd_pcie_cap_emit() just in case user accesses a invalid
address via RCD sysfs.

Fixes: c5eaec79fa43 ("cxl/pci: Add sysfs attribute for CXL 1.1 device link status")
Signed-off-by: Li Ming <ming.li@zohomail.com>
---
 drivers/cxl/pci.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index b2cb81f6d9e7..e53b1c95a248 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -836,6 +836,9 @@  static ssize_t rcd_pcie_cap_emit(struct device *dev, u16 offset, char *buf, size
 	if (!root_dev)
 		return -ENXIO;
 
+	if (!dport->regs.rcd_pcie_cap)
+		return -ENXIO;
+
 	guard(device)(root_dev);
 	if (!root_dev->driver)
 		return -ENXIO;