PCI: dwc: Protect root bus removal with rescan lock

Hold the pci_rescan_remove_lock lock while stopping and removing a root bus
to avoid racing with concurrent rescan or hotplug operations triggered via
sysfs.  Such races may lead to use-after-free issues or system crashes.

Signed-off-by: Hans Zhang <18255117159@163.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260521161822.132996-3-18255117159@163.com

diff --git a/drivers/pci/controller/dwc/pcie-designware-host.c b/drivers/pci/controller/dwc/pcie-designware-host.c
index c9517a34883686a37d63b33671dcedd544ac07da..f856ac2fb15d83a3ef4e2328c596932b9127bb52 100644 (file)
--- a/drivers/pci/controller/dwc/pcie-designware-host.c
+++ b/drivers/pci/controller/dwc/pcie-designware-host.c
@@ -703,8 +703,10 @@ void dw_pcie_host_deinit(struct dw_pcie_rp *pp)
 
        dwc_pcie_debugfs_deinit(pci);
 
+       pci_lock_rescan_remove();
        pci_stop_root_bus(pp->bridge->bus);
        pci_remove_root_bus(pp->bridge->bus);
+       pci_unlock_rescan_remove();
 
        dw_pcie_stop_link(pci);