[PATCH] ACPI: pfr_telemetry: Fix info leak in pfrt_log_ioctl()

From: Dan Carpenter
Date: Fri Jan 07 2022 - 02:34:29 EST


The "data_info" struct is copied to the user. It has a 4 byte struct
hole after the last struct member so we need to memset that to avoid
copying uninitialized stack data to the user.

Fixes: b0013e037a8b ("ACPI: Introduce Platform Firmware Runtime Telemetry driver")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
When you're adding a new driver to the kernel then please use the new
driver's prefix instead of just the subsystem prefix.

Bad: ACPI: Introduce Platform Firmware Runtime Telemetry driver
Good: ACPI / pfr_telemetry: Introduce Platform Firmware Runtime Telemetry driver

Otherwise it's just up to me to guess what prefix you wanted.

drivers/acpi/pfr_telemetry.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/acpi/pfr_telemetry.c b/drivers/acpi/pfr_telemetry.c
index da50dd80192c..9abf350bd7a5 100644
--- a/drivers/acpi/pfr_telemetry.c
+++ b/drivers/acpi/pfr_telemetry.c
@@ -83,6 +83,7 @@ static int get_pfrt_log_data_info(struct pfrt_log_data_info *data_info,
union acpi_object *out_obj, in_obj, in_buf;
int ret = -EBUSY;

+ memset(data_info, 0, sizeof(*data_info));
memset(&in_obj, 0, sizeof(in_obj));
memset(&in_buf, 0, sizeof(in_buf));
in_obj.type = ACPI_TYPE_PACKAGE;
--
2.20.1