From: "Rafael J. Wysocki" <[email protected]>
After commit 9b311b7313d6 ("ACPI: NFIT: Install Notify() handler before
getting NFIT table"), acpi_nfit_probe() installs an ACPI notify handler
for the NFIT device before checking the presence of the NFIT table. If
that table is not there, 0 is returned without allocating the acpi_desc
object and setting the driver data pointer of the NFIT device. If the
platform firmware triggers an NFIT_NOTIFY_UC_MEMORY_ERROR notification
on the NFIT device at that point, acpi_nfit_uc_error_notify() will
dereference a NULL pointer.
Prevent that from occurring by adding an acpi_desc check against NULL
to acpi_nfit_uc_error_notify().
Fixes: 9b311b7313d6 ("ACPI: NFIT: Install Notify() handler before getting NFIT
table")
Signed-off-by: Rafael J. Wysocki <[email protected]>
Cc: All applicable <[email protected]>
---
drivers/acpi/nfit/core.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 5cab62f618c8..8024cd3cad14 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -3442,6 +3442,9 @@ static void acpi_nfit_uc_error_notify(struct device *dev,
acpi_handle handle)
{
struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(dev);
+ if (!acpi_desc)
+ return;
+
if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON)
acpi_nfit_ars_rescan(acpi_desc, ARS_REQ_LONG);
else
--
2.51.0
