asus-laptop: Fix an uninitialized variable

commit 6c683c6887e4addcd6bd1ddce08cafccb0a21e32 upstream.

The value returned by acpi_evaluate_integer() is not checked,
but the result is not always successful, so it is necessary to
add a check of the returned value.

If the result remains negative during three iterations of the loop,
then the uninitialized variable 'val' will be used in the clamp_val()
macro, so it must be initialized with the current value of the 'curr'
variable.

In this case, the algorithm should be less noisy.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: b23910c219 ("asus-laptop: Pegatron Lucid accelerometer")
Cc: stable@vger.kernel.org
Signed-off-by: Denis Arefev <arefev@swemel.ru>
Link: https://lore.kernel.org/r/20250403122603.18172-1-arefev@swemel.ru
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Denis Arefev
2025-04-03 15:26:01 +03:00
committed by Greg Kroah-Hartman
parent a12c145778
commit e446b60a2b

View File

@@ -427,11 +427,14 @@ static int asus_pega_lucid_set(struct asus_laptop *asus, int unit, bool enable)
static int pega_acc_axis(struct asus_laptop *asus, int curr, char *method)
{
unsigned long long val = (unsigned long long)curr;
acpi_status status;
int i, delta;
unsigned long long val;
for (i = 0; i < PEGA_ACC_RETRIES; i++) {
acpi_evaluate_integer(asus->handle, method, NULL, &val);
for (i = 0; i < PEGA_ACC_RETRIES; i++) {
status = acpi_evaluate_integer(asus->handle, method, NULL, &val);
if (ACPI_FAILURE(status))
continue;
/* The output is noisy. From reading the ASL
* dissassembly, timeout errors are returned with 1's
* in the high word, and the lack of locking around