Unverified Commit 6c683c68 authored by Denis Arefev's avatar Denis Arefev Committed by Ilpo Järvinen
Browse files

asus-laptop: Fix an uninitialized variable 



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: b23910c2 ("asus-laptop: Pegatron Lucid accelerometer")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarDenis Arefev <arefev@swemel.ru>
Link: https://lore.kernel.org/r/20250403122603.18172-1-arefev@swemel.ru


Reviewed-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
parent d8455a63

drivers/platform/x86/asus-laptop.c

+6 −3
Original line number Diff line number Diff line
@@ -426,11 +426,14 @@ 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