This is a note to let you know that I've just added the patch titled
power: supply: axp288_fuel_gauge: Fix external_power_changed race
to the 6.1-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:
power-supply-axp288_fuel_gauge-fix-external_power_changed-race.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From f8319774d6f1567d6e7d03653174ab0c82c5c66d Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@xxxxxxxxxx>
Date: Sat, 15 Apr 2023 18:07:30 +0200
Subject: power: supply: axp288_fuel_gauge: Fix external_power_changed race
From: Hans de Goede <hdegoede@xxxxxxxxxx>
commit f8319774d6f1567d6e7d03653174ab0c82c5c66d upstream.
fuel_gauge_external_power_changed() dereferences info->bat,
which gets sets in axp288_fuel_gauge_probe() like this:
info->bat = devm_power_supply_register(dev, &fuel_gauge_desc, &psy_cfg);
As soon as devm_power_supply_register() has called device_add()
the external_power_changed callback can get called. So there is a window
where fuel_gauge_external_power_changed() may get called while
info->bat has not been set yet leading to a NULL pointer dereference.
Fixing this is easy. The external_power_changed callback gets passed
the power_supply which will eventually get stored in info->bat,
so fuel_gauge_external_power_changed() can simply directly use
the passed in psy argument which is always valid.
Fixes: 30abb3d07929 ("power: supply: axp288_fuel_gauge: Take lock before updating the valid flag")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/power/supply/axp288_fuel_gauge.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/power/supply/axp288_fuel_gauge.c b/drivers/power/supply/axp288_fuel_gauge.c
index 05f413178462..3be6f3b10ea4 100644
--- a/drivers/power/supply/axp288_fuel_gauge.c
+++ b/drivers/power/supply/axp288_fuel_gauge.c
@@ -507,7 +507,7 @@ static void fuel_gauge_external_power_changed(struct power_supply *psy)
mutex_lock(&info->lock);
info->valid = 0; /* Force updating of the cached registers */
mutex_unlock(&info->lock);
- power_supply_changed(info->bat);
+ power_supply_changed(psy);
}
static struct power_supply_desc fuel_gauge_desc = {
--
2.40.1
Patches currently in stable-queue which might be from hdegoede@xxxxxxxxxx are
queue-6.1/platform-x86-hp-wmi-fix-cast-to-smaller-integer-type-warning.patch
queue-6.1/platform-x86-intel-ifs-annotate-work-queue-on-stack-so-object-debug-does-not-complain.patch
queue-6.1/power-supply-bq25890-fix-external_power_changed-race.patch
queue-6.1/power-supply-axp288_fuel_gauge-fix-external_power_changed-race.patch
