ACPI / PCI: fix acpi_pci_irq_enable() memory leak

BugLink: https://bugs.launchpad.net/bugs/1847155
[ Upstream commit 29b49958cf73b439b17fa29e9a25210809a6c01c ]

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@cs.uga.edu>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

diff --git a/drivers/acpi/pci_irq.c b/drivers/acpi/pci_irq.c
index c576a6fe4ebb3044fc8f268fe338d3a50084cd6f..94ded9513c73b0bede043e85448251813b32806c 100644 (file)
--- a/drivers/acpi/pci_irq.c
+++ b/drivers/acpi/pci_irq.c
@@ -462,8 +462,10 @@ 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",