In the Linux kernel, the following vulnerability has been resolved:

PCI: dwc: Avoid dwc_pcie_rasdes_debugfs_deinit() NULL dereference when no RAS DES capability

dwc_pcie_rasdes_debugfs_init() returns success when the controller has no
RAS DES capability, leaving pci->debugfs->rasdes_info unset. The common
debugfs teardown path still calls dwc_pcie_rasdes_debugfs_deinit(), which
dereferences rasdes_info unconditionally.

Return early when no RAS DES state was allocated. In that case no RAS DES
mutex was initialized, so there is nothing to destroy.

[mani: reworded subject]