[PATCH 5.15.y 3/3] power: supply: lp8788-charger: fix use-after-free on remove

[Sasha Levin <sashal@kernel.org>]

From: Fan Wu <fanwu01@zju.edu.cn>

[ Upstream commit 831c29a12d560f8a3225f43050b3fbb5dfd79c66 ]

lp8788_charger_remove() flushes charger_work before unregistering the
IRQs. An IRQ thread can queue charger_work after flush_work() has
returned. The work can then run after devres frees pchg and dereference
it in lp8788_charger_event().

Unregister the IRQs first. free_irq() waits for any running threaded
handler, so no handler can queue more work afterwards. Then use
cancel_work_sync() to cancel pending work or wait for running work to
finish.

This issue was found by an in-house static analysis tool.

Fixes: 98a276649358 ("power_supply: Add new lp8788 charger driver")
Cc: stable@vger.kernel.org
Assisted-by: Codex:gpt-5.6
Signed-off-by: Fan Wu <fanwu01@zju.edu.cn>
Link: https://patch.msgid.link/20260802035442.421697-1-fanwu01@zju.edu.cn
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/power/supply/lp8788-charger.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/supply/lp8788-charger.c b/drivers/power/supply/lp8788-charger.c
index 54f663ba95700..3cd2238fc5d8d 100644
--- a/drivers/power/supply/lp8788-charger.c
+++ b/drivers/power/supply/lp8788-charger.c
@@ -711,8 +711,8 @@ static void lp8788_charger_remove(struct platform_device *pdev)
 {
 	struct lp8788_charger *pchg = platform_get_drvdata(pdev);
 
-	flush_work(&pchg->charger_work);
 	lp8788_irq_unregister(pdev, pchg);
+	cancel_work_sync(&pchg->charger_work);
 }
 
 static struct platform_driver lp8788_charger_driver = {
-- 
2.53.0