[PATCH 4.14 120/185] ACPI / PCI: fix acpi_pci_irq_enable() memory leak

[Greg Kroah-Hartman]

From: Wenwen Wang <wenwen@xxxxxxxxxx>

[ 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@xxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 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 c576a6fe4ebb3..94ded9513c73b 100644
--- 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",
-- 
2.20.1