This is a note to let you know that I've just added the patch titled
ACPI: video: check for error while searching for backlight device parent
to the 6.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
acpi-video-check-for-error-while-searching-for-backl.patch
and it can be found in the queue-6.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 94e94c596b218470362258ebbd5d8cf5d62d85ac
Author: Nikita Kiryushin <kiryushin@xxxxxxxx>
Date: Thu Nov 9 16:49:25 2023 +0300
ACPI: video: check for error while searching for backlight device parent
[ Upstream commit ccd45faf4973746c4f30ea41eec864e5cf191099 ]
If acpi_get_parent() called in acpi_video_dev_register_backlight()
fails, for example, because acpi_ut_acquire_mutex() fails inside
acpi_get_parent), this can lead to incorrect (uninitialized)
acpi_parent handle being passed to acpi_get_pci_dev() for detecting
the parent pci device.
Check acpi_get_parent() result and set parent device only in case of success.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 9661e92c10a9 ("acpi: tie ACPI backlight devices to PCI devices if possible")
Signed-off-by: Nikita Kiryushin <kiryushin@xxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/acpi/acpi_video.c b/drivers/acpi/acpi_video.c
index 6cee536c229a..375010e575d0 100644
--- a/drivers/acpi/acpi_video.c
+++ b/drivers/acpi/acpi_video.c
@@ -1713,12 +1713,12 @@ static void acpi_video_dev_register_backlight(struct acpi_video_device *device)
return;
count++;
- acpi_get_parent(device->dev->handle, &acpi_parent);
-
- pdev = acpi_get_pci_dev(acpi_parent);
- if (pdev) {
- parent = &pdev->dev;
- pci_dev_put(pdev);
+ if (ACPI_SUCCESS(acpi_get_parent(device->dev->handle, &acpi_parent))) {
+ pdev = acpi_get_pci_dev(acpi_parent);
+ if (pdev) {
+ parent = &pdev->dev;
+ pci_dev_put(pdev);
+ }
}
memset(&props, 0, sizeof(struct backlight_properties));
