In the Linux kernel, the following vulnerability has been resolved: serial: pch: Fix PCI device refcount leak in pchrequestdma() As comment of pcigetslot() says, it returns a pcidevice with its refcount increased. The caller must decrement the reference count by calling pcidevput(). Since 'dmadev' is only used to filter the channel in filter(), we can call pcidevput() before exiting from pchrequestdma(). Add the missing pcidevput() for the normal and error path.