Re: [PATCH v2] ACPI / PCI: fix acpi_pci_irq_enable() memory leak

From: Bjorn Helgaas
Date: Mon Sep 02 2019 - 18:34:30 EST


On Mon, Sep 02, 2019 at 11:19:58PM +0200, Rafael J. Wysocki wrote:
> On Wed, Aug 21, 2019 at 5:44 AM Wenwen Wang <wenwen@xxxxxxxxxx> wrote:
> >
> > In acpi_pci_irq_enable(), 'entry' is allocated by kzalloc() in
> > acpi_pci_irq_check_entry() (invoked from acpi_pci_irq_lookup()). However,
> > it is not deallocated if acpi_pci_irq_valid() returns false, leading to a
> > memory leak. To fix this issue, free 'entry' before returning 0.
> >
> > Fixes: e237a5518425 ("x86/ACPI/PCI: Recognize that Interrupt Line 255 means
> > "not connected"")
> >
> > Signed-off-by: Wenwen Wang <wenwen@xxxxxxxxxx>
>
> Bjorn, any more comments?

Nope, looks fine to me.

> > ---
> > drivers/acpi/pci_irq.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
> > index d2549ae..dea8a60 100644
> > --- a/drivers/acpi/pci_irq.c
> > +++ b/drivers/acpi/pci_irq.c
> > @@ -449,8 +449,10 @@ int acpi_pci_irq_enable(struct pci_dev *dev)
> > * No IRQ known to the ACPI subsystem - maybe the BIOS /
> > * driver reported one, then use it. Exit in any case.
> > */
> > - if (!acpi_pci_irq_valid(dev, pin))
> > + if (!acpi_pci_irq_valid(dev, pin)) {
> > + kfree(entry);
> > return 0;
> > + }
> >
> > if (acpi_isa_register_gsi(dev))
> > dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
> > --
> > 2.7.4
> >